Masafumi Harada : 磁気共鳴スペクトルの医学応用-MRSの基礎から離礁まで-, 株式会社インナービジョン, 東京, Mar. 2012.
9.
Masafumi Harada : 磁気共鳴スペクトルの医学応用-MRSの基礎から臨床まで-, 株式会社インナービジョン, 東京, Mar. 2012.
10.
Hitoshi Kubo and Masafumi Harada : 磁気共鳴スペクトルの医学応用 -MRSの基礎から臨床まで-, インナービジョン, 東京都文京区, Mar. 2012.
11.
Yoshihiro Takegawa and Masafumi Harada : 女性医療と漢方医療, --- Great results of kampo combined with radiotherapy for cancer patients - Concomitant kampo prolongs survival in patients with cervical cancer - ---, Nagai Shoten Co., Tokyo, Apr. 2006.
(Keyword)
漢方 / 放射線治療 / 有害事象 / 延命効果 / 子宮頸癌
12.
Yoshihiro Takegawa and Masafumi Harada : 漢方の教育とEBMー統合医療の確立をめざす, Life Science Publishing Co., Ltd., Tokyo, Apr. 2006.
(Keyword)
漢方 / 十全大補湯 / 緩和医療 / 有害事象
13.
Yoshihiro Takegawa and Masafumi Harada : Effects of Kampo Combined with Radiation Therapy in Cervical Cancer, --- Can Juzen-taiho-to Prolong the Life of Cancer Patient ---, 癌と化学療法社, Tokyo, Jan. 2006.
Bollos Christine Anne Leah Locsin, Ryosuke Kasai, Hideki Otsuka, Youichi Otomi, Koji Yamaguchi, Tomomi Matsuura, Tamaki Otani, Takanori Bandoh, Yuya Ueki, Noritake Matsuda, Satoru Takashi, Shota Azane, Yamato Kunikane, Shoichiro Takao, Shusuke Yagi, Masataka Sata, Hitoshi Ikushima and Masafumi Harada : Ventilation/Perfusion Mismatch in Pulmonary Vein Stenosis Secondary to Atrial Fibrillation Ablation, Asia Oceania Journal of Nuclear Medicine & Biology, 2024.
(Summary)
We present two patients with a history of paroxysmal atrial fibrillation who developed pulmonary vein stenosis (PVS) following atrial fibrillation (AF) ablation. Case 1 involved a female patient in her 50s who was asymptomatic for pulmonary symptoms but was found to have a high degree of left superior PVS 15 months after AF ablation. This was demonstrated using contrast-enhanced computed tomography (CE-CT) and supported by findings of perfusion defects on ventilation-perfusion (V/Q) scan. Case 2 was a male patient in his 60s who developed progressive left superior PVS nine months after AF ablation, evidenced by serial CE-CT and V/Q scans. PVS is a rare but well-known complication of pulmonary vein ablation for the treatment of AF that can lead to severe complications if left untreated. V/Q scans effectively assess the functional significance of PVS by detecting abnormal blood flow segments. Although a V/Q mismatch characterized by reduced perfusion defects is more commonly used in evaluating pulmonary embolism, PVS should not be disregarded as a differential diagnosis. Few studies emphasize the utility of V/Q scans in managing PVS and highlight V/Q mismatch as a notable finding. This case report aimed to highlight their significance.
MATSUDA Noritake, Hideki Otsuka, Ryosuke Kasai, Tamaki Otani, BOLLOS CHRISTINE ANNE LEAH LOCSIN, Shota Azane, Yamato Kunikane, Youichi Otomi, UEKI Yuya, Mana Okabe, Masafumi Amano, Masanori Tamaki, Shu Wakino, Shoichiro Takao and Masafumi Harada : Quantitative evaluation of 67Gacitrate scintigraphy in the management of nephritis, Scientific Reports, Vol.14, No.16313, 16313, 2024.
(Summary)
In Ga-citrate scintigraphy (Ga-S), visual assessment is used by evaluating renal-uptake comparison with liver and spine and is simple and objective. We adopted the standardized uptake value (SUV) for Ga-citrate and proposed two quantitative indices, active nephritis volume (ANV) and total nephritis uptake (TNU). This study clarified the utility of new Ga-S-based quantitative indices in nephritis management. Before SUV measurement, the Becquerel calibration factor of Ga-citrate was obtained using a phantom experiment. Seventy patients who underwent SPECT/CT imaging were studied. SUV, ANV, and TNU were calculated using a quantitative analysis software for bone SPECT. SUV, ANV, and TNU were analyzed using the (1) threshold method (set 40%) and constant-value method for (2) vertebral SUV, and (3) vertebral SUV. ROC analysis was used to evaluate SUV, ANV, and TNU diagnostic abilities to distinguish nephritis presence and absence as well as interstitial nephritis (IN) and non-IN. The area under the curve (AUC) for nephritis presence or absence had a good value (0.80) for SUV (1), ANV (3), and TNU (3). The AUC for differentiation between IN and non-IN groups had a good value (0.80) for SUV (1). Thus, the new Ga-S-based quantitative indices were useful to evaluate nephritis and distinguish IN and non-IN.
(Keyword)
Humans / Male / Female / Middle Aged / Gallium Radioisotopes / Aged / Gallium / Adult / Nephritis / Citrates / ROC Curve / Aged, 80 and over / Radiopharmaceuticals / Single Photon Emission Computed Tomography Computed Tomography
Yasuhisa Kanematsu, Yuki Kanazawa, Kenji Shimada, Masaaki Korai, Takeshi Miyamoto, Shu Sogabe, Manabu Ishihara, Izumi Yamaguchi, Takeshi Oya, Nobuaki Yamamoto, Yuki Yamamoto, Miyoshi Mitsuharu, Masafumi Harada and Yasushi Takagi : Characterization of carotid plaques using chemical exchange saturation transfer imaging, Neuroradiology, Vol.66, No.9, 1617-1624, 2024.
(Summary)
The preoperative assessment of carotid plaques is necessary to render revascularization safe and effective. The aim of this study is to evaluate the usefulness of chemical exchange saturation transfer (CEST)-MRI, particularly amide proton transfer (APT) imaging as a preoperative carotid plaque diagnostic tool. We recorded the APT signal intensity on concentration maps of 34 patients scheduled for carotid endarterectomy. Plaques were categorized into group A (APT signal intensity ≥ 1.90 E-04; n = 12) and group B (APT signal intensity < 1.90 E-04; n = 22). Excised plaques were subjected to histopathological assessment and, using the classification promulgated by the American Heart Association, they were classified as intraplaque hemorrhage-positive [type VI-positive (tVI)] and -negative [no intraplaque hemorrhage (tVI)]. Of the 34 patients, 22 (64.7%) harbored tVI- and 12 (35.3%) had tVI plaques. The median APT signals were significantly higher in tVI- than tIVI patients (2.43 E-04 (IQR = 0.98-4.00 E-04) vs 0.54 E-04 (IQR = 0.14-1.09 E-04), p < .001). Histopathologically, the number of patients with tVI plaques was significantly greater in group A (100%, n = 12) than group B (45%, n = 22) (p < .01). The number of symptomatic patients or asymptomatic patients with worsening stenosis was also significantly greater in group A than group B (75% vs 36%, p < .01). In unstable plaques with intraplaque hemorrhage and in patients with symptoms or progressive stenosis, the ATP signals were significantly elevated. CEST-MRI studies has the potential for the preoperative assessment of the plaques' characteristics.
Yuki Kanazawa, Yo Taniguchi, Masafumi Harada, Kosuke Ito and Yoshitaka Bito : Visualization of Human Brain Cortical Layers Using Quantitative Parameter Mapping on a 3 Tesla Scanner, Proceedings of ISMRM, Vol.33, 2933, 2024.
5.
Ohshiro Ryuji, Yuki Kanazawa, Akihiro Haga and Masafumi Harada : Development of numerical phantom converting from electron microscopic analysis to multi-component water fraction for MRI simulator., Proceedings of ISMRM, Vol.33, 2038, 2024.
6.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Endometriosis, a common but enigmatic disease with many faces: current concept of pathophysiology, and diagnostic strategy, Japanese Journal of Radiology, Vol.Online ahead of print, 2024.
(Summary)
Endometriosis is a benign, common, but controversial disease due to its enigmatic etiopathogenesis and biological behavior. Recent studies suggest multiple genetic, and environmental factors may affect its onset and development. Genomic analysis revealed the presence of cancer-associated gene mutations, which may reflect the neoplastic aspect of endometriosis. The management has changed dramatically with the development of fertility-preserving, minimally invasive therapies. Diagnostic strategies based on these recent basic and clinical findings are reviewed. With a focus on the presentation of clinical cases, we discuss the imaging manifestations of endometriomas, deep endometriosis, less common site and rare site endometriosis, various complications, endometriosis-associated tumor-like lesions, and malignant transformation, with pathophysiologic conditions.
Shun Kitano, Yuki Kanazawa, Masafumi Harada, Yo Taniguchi, Hiroaki Hayashi, Yuki Matsumoto, Kosuke Ito, Yoshitaka Bito and Akihiro Haga : Conversion Map from Quantitative Parameter Mapping to Myelin Water Fraction: Comparison with R1·R2* and Myelin Water Fraction in White Matter., Magma, 2024.
(Summary)
To clarify the relationship between myelin water fraction (MWF) and R⋅R and to develop a method to calculate MWF directly from parameters derived from QPM, i.e., MWF converted from QPM (MWF). Subjects were 12 healthy volunteers. On a 3 T MR scanner, dataset was acquired using spoiled gradient-echo sequence for QPM. MWF and R⋅R maps were derived from the multi-gradient-echo (mGRE) dataset. Volume-of-interest (VOI) analysis using the JHU-white matter (WM) atlas was performed. All the data in the 48 WM regions measured VOI were plotted, and quadratic polynomial approximations of each region were derived from the relationship between R·R and the two-pool model-MWF. The R·R map was converted to MWF map. MWF atlas template was generated using converted to MWF from R·R per WM region. The mean MWF and R·R values for the 48 WM regions were 11.96 ± 6.63%, and 19.94 ± 4.59 s, respectively. A non-linear relationship in 48 regions of the WM between MWF and R·R values was observed by quadratic polynomial approximation (R ≥ 0.963, P < 0.0001). MWF map improved image quality compared to the mGRE-MWF map. Myelin water atlas template derived from MWF may be generated with combined multiple WM regions.
Natsuki Ikemitsu, Yuki Kanazawa, Akihiro Haga, Hiroaki Hayashi, Yuki Matsumoto and Masafumi Harada : Determination of Alzheimer's disease based on morphology and atrophy using machine learning combined with automated segmentation, Acta Radiologica, Vol.65, No.4, 359-366, 2024.
(Summary)
To evaluate the degree of cerebral atrophy for Alzheimer's disease (AD), voxel-based morphometry has been performed with magnetic resonance imaging. Detailed morphological changes in a specific tissue area having the most evidence of atrophy were not considered by the machine-learning technique. To develop a machine-learning system that can capture morphology features for determination of atrophy of brain tissue in early-stage AD and classification of healthy participants or patients. Three-dimensional T1-weighted (3D-T1W) data were obtained from AD Neuroimaging Initiative (200 healthy controls and 200 patients with early-stage AD). Automated segmentation of 3D-T1W data was performed. Deep learning (DL) and support vector machine (SVM) were trained using 66-segmented volume values as input and AD diagnosis as output. DL was performed using 66 volume values or gray matter (GM) and white matter (WM) volume values. SVM learning was performed using 66 volume values and six regions with high variable importance. 3D convolutional neural network (3D-CNN) was trained using the segmented images. Accuracy and area under curve (AUC) were obtained. Variable importance was evaluated from logistic regression analysis. DL for GM and WM volume values, accuracy 0.6; SVM for all volume values, accuracy 0.82 and AUC 0.81; DL for all volume values, accuracy 0.82 and AUC 0.8; 3D-CNN using segmental images of the whole brain, accuracy 0.5 and AUC 0.51. SVM using volume values of six regions, accuracy 0.82; image-based 3D-CNN, highest accuracy 0.69. Our results show that atrophic features are more considerable than morphological features in the early detection of AD.
(Keyword)
Alzheimer's disease / magnetic resonance imaging / convolutional neural network / deep learning / support vector machine
Daiki Chiba, Yuki Kanazawa, Tosiaki Miyati, Masafumi Harada, Mitsuharu Miyoshi, Hiroaki Hayashi and Akihiro Haga : Simplified assessment for chemical exchanged saturation transfer (CEST) imaging: local offset frequency and CEST effect, Radiological Physics and Technology, Vol.17, No.1, 93-102, 2024.
(Summary)
The aim of this study is to develop a novel phantom for the evaluation of clinical CEST imaging settings, e.g., B0 and B1 field inhomogeneities, CEST contrast, and post-processing. We made a phantom composed of two slice sections: a grid section for local offset frequency evaluation and a sample section for CEST effect evaluation using different concentrations of an egg white albumin solution. On a 3 Tesla MR scanner, a phantom study was performed using CEST imaging; the mean B1 amplitudes were set at 1.2 and 1.9 µT, and CEST images with and without B0 corrections were acquired. Next, region of interest (ROI) analysis was performed for each slice. Then, CEST images with and without B0 corrections were compared at each B1 amplitude. The B0 corrected Z-spectrums at each local region in the grid section showed a shifting of the curve bottom to 0 ppm. Z-spectrum at B1 = 1.9 µT showed a broader curve shape than that at 1.2 µT. Moreover, MTRasym values at 3.5 ppm for each albumin sample at B1 = 1.9 µT were about two times higher than those at 1.2 µT. Our phantom enabled us to evaluate and optimize B0 inhomogeneity and the CEST effect at the B1 amplitude.
(Keyword)
Magnetic Resonance Imaging / Phantoms, Imaging / Albumins
Yuya Ueki, Hideki Otsuka, Tamaki Otani, Ryosuke Kasai, Youichi Otomi, Daiki Ikemitsu, Shota Azane, Yamato Kunikane, Takanori Bandoh, Noritake Matsuda, Yasuyuki Okada, Tetsuji Takayama and Masafumi Harada : Combined visual and quantitative assessment of somatostatin receptor scintigraphy for staging and restaging of neuroendocrine tumors, Japanese Journal of Radiology, Vol.42, No.5, 519-535, 2024.
(Summary)
Somatostatin receptor scintigraphy (SRS) using In-DTPA-DPhe-octreotide (pentetreotide) has become an integral part of neuroendocrine neoplasm management. The lack of precise quantification is a disadvantage of SRS. This study aimed to adapt the standardized uptake value (SUV) to SRS, establish the SUV range for physiological uptake in the liver, kidney, and spleen, and elucidate the utility of combined visual and quantitative SRS assessment for staging and restaging of neuroendocrine tumors (NETs). This study included 21 patients with NETs who underwent In-pentetreotide SRS. The SUV of physiological and pathological uptake was calculated using bone single-photon emission computed tomography (SPECT) quantitative analysis software (GI-BONE). For visual analysis, the primary and metastatic lesions were scored visually on planar and SPECT images using a five-point scale. We assessed the relationships between the SUVs of the liver, kidney, and spleen in the dual phase, and among quantitative indices, visual score, and pathological lesions classification. Sixty-three NEN lesions were evaluated. The mean ± standard deviation maximum SUVs (SUVmax) were liver: 4 h, 2.6 ± 1.0; 24 h, 2.2 ± 1.0; kidney: 4 h, 8.9 ± 1.8; 24 h, 7.0 ± 2.0; and spleen; 4 h, 11.3 ± 4.5; 24 h, 11.5 ± 7.6. Higher SUVmax was significantly associated with higher visual scores on dual-phase SPECT (4 h, p < 0.001; 24 h, p < 0.001) (4 h: scores 3 and 4, p < 0.05; scores 3 and 5: p < 0.01; scores 4 and 5: p < 0.01; 24 h: scores 3 and 4, p = 0.0748; scores 3 and 5: p < 0.01; scores 4 and 5: p < 0.01). We adapted the SUV to SRS and established the range of SUV for physiological uptake in the liver, kidney, and spleen. Combined visual and quantitative assessment is useful for imaging individual lesions in greater detail, and may serve as a new tumor marker of SRS for staging and restaging of NETs.
Akinari Kasai, Jinsei Miyoshi, Yasushi Sato, Koichi Okamoto, Hiroshi Miyamoto, Takashi Kawanaka, Chisato Tonoiso, Masafumi Harada, Masakazu Goto, Takahiro Yoshida, Akihiro Haga and Tetsuji Takayama : A novel CT-based radiomics model for predicting response and prognosis of chemoradiotherapy in esophageal squamous cell carcinoma., Scientific Reports, Vol.14, No.1, 2039, 2024.
(Summary)
No clinically relevant biomarker has been identified for predicting the response of esophageal squamous cell carcinoma (ESCC) to chemoradiotherapy (CRT). Herein, we established a CT-based radiomics model with artificial intelligence (AI) to predict the response and prognosis of CRT in ESCC. A total of 44 ESCC patients (stage I-IV) were enrolled in this study; training (n = 27) and validation (n = 17) cohorts. First, we extracted a total of 476 radiomics features from three-dimensional CT images of cancer lesions in training cohort, selected 110 features associated with the CRT response by ROC analysis (AUC ≥ 0.7) and identified 12 independent features, excluding correlated features by Pearson's correlation analysis (r ≥ 0.7). Based on the 12 features, we constructed 5 prediction models of different machine learning algorithms (Random Forest (RF), Ridge Regression, Naive Bayes, Support Vector Machine, and Artificial Neural Network models). Among those, the RF model showed the highest AUC in the training cohort (0.99 [95%CI 0.86-1.00]) as well as in the validation cohort (0.92 [95%CI 0.71-0.99]) to predict the CRT response. Additionally, Kaplan-Meyer analysis of the validation cohort and all the patient data showed significantly longer progression-free and overall survival in the high-prediction score group compared with the low-prediction score group in the RF model. Univariate and multivariate analyses revealed that the radiomics prediction score and lymph node metastasis were independent prognostic biomarkers for CRT of ESCC. In conclusion, we have developed a CT-based radiomics model using AI, which may have the potential to predict the CRT response as well as the prognosis for ESCC patients with non-invasiveness and cost-effectiveness.
Yuki Kanazawa, Natsuki Ikemitsu, Yuki Kinjyo, Masafumi Harada, Hiroaki Hayashi, Yo Taniguchi, Kosuke Ito, Yoshitaka Bito, Yuki Matsumoto and Akihiro Haga : Differences of white matter structure for diffusion kurtosis imaging using voxel-based morphometry and connectivity analysis, BJR Open, Vol.6, No.1, 1-7, 2024.
(Summary)
In a clinical study, diffusion kurtosis imaging (DKI) has been used to visualize and distinguish white matter (WM) structures' details. The purpose of our study is to evaluate and compare the diffusion tensor imaging (DTI) and DKI parameter values to obtain WM structure differences of healthy subjects. Thirteen healthy volunteers (mean age, 25.2 years) were examined in this study. On a 3-T MRI system, diffusion dataset for DKI was acquired using an echo-planner imaging sequence, and T-weghted (Tw) images were acquired. Imaging analysis was performed using Functional MRI of the brain Software Library (FSL). First, registration analysis was performed using the Tw of each subject to MNI152. Second, DTI (eg, fractional anisotropy [FA] and each diffusivity) and DKI (eg, mean kurtosis [MK], radial kurtosis [RK], and axial kurtosis [AK]) datasets were applied to above computed spline coefficients and affine matrices. Each DTI and DKI parameter value for WM areas was compared. Finally, tract-based spatial statistics (TBSS) analysis was performed using each parameter. The relationship between FA and kurtosis parameters (MK, RK, and AK) for WM areas had a strong positive correlation (FA-MK, = 0.93; FA-RK, = 0.89) and a strong negative correlation (FA-AK, = 0.92). When comparing a TBSS connection, we found that this could be observed more clearly in MK than in RK and FA. WM analysis with DKI enable us to obtain more detailed information for connectivity between nerve structures. Quantitative indices of neurological diseases were determined using segmenting WM regions using voxel-based morphometry processing of DKI images.
Saya Matsuzaki, Eiji Hase, Hiroki Takanari, Yuri Hayashi, Yusaku Hayashi, Haruto Oshikata, Takeo Minamikawa, Satoko Kimura, Mayuko Shimizu, Takeshi Yasui, Masafumi Harada and Koichi Tsuneyama : Quantification of collagen fiber properties in alcoholic liver fibrosis using polarization-resolved second harmonic generation microscopy., Scientific Reports, Vol.13, No.1, 22100, 2023.
(Summary)
Liver fibrosis is assessed mainly by conventional staining or second harmonic generation (SHG) microscopy, which can only provide collagen content in fibrotic area. We propose to use polarization-resolved SHG (PR-SHG) microscopy to quantify liver fibrosis in terms of collagen fiber orientation and crystallization. Liver samples obtained from autopsy cases with fibrosis stage of F0-F4 were evaluated with an SHG microscope, and 12 consecutive PR-SHG images were acquired while changing the polarization azimuth angle of the irradiated laser from 0° to 165° in 15° increments using polarizer. The fiber orientation angle (φ) and degree (ρ) of collagen were estimated from the images. The SHG-positive area increased as the fibrosis stage progressed, which was well consistent with Sirius Red staining. The value of φ was random regardless of fibrosis stage. The mean value of ρ (ρ-mean), which represents collagen fiber crystallinity, varied more as fibrosis progressed to stage F3, and converged to a significantly higher value in F4 than in other stages. Spatial dispersion of ρ (ρ-entropy) also showed increased variation in the stage F3 and decreased variation in the stage F4. It was shown that PR-SHG could provide new information on the properties of collagen fibers in human liver fibrosis.
Koji Fukushima, T Yoshida, Hiroki Yamazaki, N Takamatsu, T Nagai, Yusuke Osaki, Masafumi Harada, I Nishino, N Okiyama, K Sugie and Yuishin Izumi : A Case of Anti-NXP2 Antibody-positive Juvenile Dermatomyositis with Characteristic Fascial Thickening on Muscle Ultrasound and Improvement with Immunotherapy, Internal Medicine, 2023.
(Summary)
We herein report a 12-year-old boy who presented with a fever, erythematous rash on the cheeks, back pain, and dysphagia. Blood tests revealed increased creatine kinase levels, and muscle ultrasonography (MUS) revealed characteristic fascial thickening in the lumbar paraspinal muscles, where myalgia was prominent. Sarcoplasmic expression of myxovirus-resistant protein A on a muscle biopsy and the presence of anti-nuclear matrix protein 2 (NXP2) antibodies confirmed the diagnosis of dermatomyositis. Prednisolone and intravenous immunoglobulin therapy improved the clinical and laboratory parameters as well as fascial thickening. MUS is useful for evaluating fasciitis associated with anti-NXP2 autoantibodies and monitoring therapeutic efficacy.
Mayumi Takeuchi, Kenji Matsuzaki, Yoshimi Bando and Masafumi Harada : Dynamic contrast-enhanced MR imaging of uterine endometrial carcinoma with/without squamous differentiation, Abdominal Radiology, Vol.48, No.8, 2494-2502, 2023.
(Summary)
Purpose: Endometrial carcinoma with strong enhancement on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is suggestive of high-grade type II endometrial carcinoma. However, low-grade type I endometrial carcinoma may also sometimes show strong enhancement. We hypothesized that squamous differentiation would contribute to the strong enhancement at the early phase on DCE-MRI-like uterine cervical squamous cell carcinoma and compared the DCE-MRI findings of endometrial carcinoma with and without squamous differentiation. Methods: DCE-MRI of endometrial carcinoma including 41 low-grade type I endometrial carcinomas without squamous differentiation (LG), 39 low-grade type I endometrial carcinomas with squamous differentiation (LGSD), and 20 high-grade type II endometrial carcinomas (HG) was retrospectively evaluated. Results: Significant difference in the time-intensity curves was found between LG and HG and LG and LGSD, whereas no significant difference was seen between HG and LGSD. Curve type 3 (initial signal rise which is steeper than that of the myometrium) was more frequent in HG (60%) and LGSD (77%) than in LG (34%). Conclusion: It should be recognized as a pitfall that high-grade type II endometrial carcinoma and low-grade type I endometrial carcinoma with squamous differentiation may show similar early strong enhancement on DCE-MRI.
Noritake Matsuda, Hideki Otsuka, Tamaki Otani, Shota Azane, Yamato Kunikane, Yoichi Otomi, Yuya Ueki, Masahiro Kubota, Masafumi Amano, Shusuke Yagi, Masataka Sata and Masafumi Harada : New quantitative indices of cardiac amyloidosis with 99mTc-pyrophosphate scintigraphy, Japanese Journal of Radiology, Vol.41, No.4, 428-436, 2023.
(Summary)
Amyloid light chain (AL) and transthyretin (ATTR) are the major subtypes of cardiac amyloidosis (CA). Tc-pyrophosphate (PYP) scintigraphy is used to differentiate ATTR from other CA subtypes. We adapted the standardized uptake value (SUV) for Tc-PYP and proposed two quantitative indices, amyloid deposition volume (AmyDV) and total amyloid uptake (TAU). This study aimed to evaluate the utility of these quantitative indices in differentiating ATTR from non-ATTRs. Before the SUV measurement, the Becquerel calibration factor (BCF) of Tc was obtained by a phantom experiment. Thirty-two patients who had undergone hybrid SPECT/CT imaging 3 h after injection of Tc-PYP (370 MBq) were studied. CT attenuation correction for image reconstruction was applied in all. We calculated SUV, AmyDV, and TAU using a quantitative analysis software program for bone SPECT (GI-BONE) and analyzed AmyDV using two methods: threshold method (set 40%); and constant value method (average SUV of ribs). We assessed the diagnostic ability of heart-to-contralateral lung (H/CL) ratio, SUV, AmyDV, and TAU to differentiate ATTR from non-ATTR using receiver operating characteristic (ROC) analysis. Statistically significant differences in all quantitative indices were observed between ATTR and non-ATTR. The area under the curve of each quantitative index for discriminating between ATTR and non-ATTR were as follows: H/CL, 0.997; SUV, 0.953; SUV (M1), 0.964; SUV (M2), 0.969; AmyDV (M1), 0.875; AmyDV (M2), 0.974; and TAU, 0.974. The AmyDV (M2) had higher diagnostic ability than AmyDV (M1). Thus, TAU was calculated as AmyDV (M2) × SUV (M2). In the ROC curve, SUV, AmyDV, and TAU had almost the same diagnostic ability as H/CL in distinguishing ATTR from non-ATTRs. We propose two novel 3D-based quantitative parameters (AmyDV and TAU) that have almost equal ability to discriminate ATTR from non-ATTR.
Kenji Yamada, Yoshiki Kawata, Masafumi Amano, Hidenobu Suzuki, Masahide Tominaga, Motoharu Sasaki, Hikaru Nishiyama, Masafumi Harada and Noboru Niki : Influence of Pitch on Surface Dose Distribution and Image Noise of Computed Tomography Scans, Sensors, Vol.23, No.7, 3472, 2023.
(Summary)
This study evaluated the effect of pitch on 256-slice helical computed tomography (CT) scans. Cylindrical water phantoms (CWP) were measured using axial and helical scans with various pitch values. The surface dose distributions of CWP were measured, and reconstructed images were obtained using filtered back-projection (FBP) and iterative model reconstruction (IMR). The image noise in each reconstructed image was decomposed into a baseline component and another component that varied along the z-axis. The baseline component of the image noise was highest at the center of the reconstructed image and decreased toward the edges. The normalized 2D power spectra for each pitch were almost identically distributed. Furthermore, the ratios of the 2D power spectra for IMR and FBP at different pitch values were obtained. The magnitudes of the components varying along the z-axis were smallest at the center of the reconstructed image and increased toward the edge. The ratios of the 3D power spectra on the fx axis for IMR and FBP at different pitch values were obtained. The results showed that the effect of the pitch was related to the component that varied along the z-axis. Furthermore, the pitch had a smaller effect on IMR than on FBP.
(Keyword)
Helical computed tomography / Pitch / Surface dose distribution / FBP / IMR / Image noise / Power spectrum
Yuka Hiroshima, Youichi Otomi, Takayoshi Shinya, Hideki Otsuka and Masafumi Harada : F-FDG PET/CT in the Evaluation of Adult Alveolar Rhabdomyosarcoma., Molecular Imaging and Radionuclide Therapy, Vol.32, No.1, 62-64, 2023.
(Summary)
C-methionine PET/CT for accurately assessing the extent of alveolar rhabdomyosarcoma, especially in cases with intracranial infiltration or those approximating the brain.
Wataru Sako, Shotaro Haji, Takashi Abe, Yusuke Osaki, Yuki Matsumoto, Masafumi Harada and Yuishin Izumi : M1/precuneus ratio as a surrogate marker of upper motor neuron sign in ALS, Journal of the Neurological Sciences, Vol.445, 120548, 2023.
(Summary)
To investigate whether primary motor cortex (M1) volume measured with an automated approach in MRI reflects upper motor neuron dysfunction and whether it can serve as a potential diagnostic and/or disease-tracking biomarker for amyotrophic lateral sclerosis (ALS). In this retrospective study, we enrolled 95 subjects, including 33 possible or laboratory supported probable ALS, 26 probable or definite ALS (Prob/Def), 2 primary lateral sclerosis patients, 8 progressive muscular atrophy patients, 19 normal controls (NC) and 7 ALS patients having a second structural MRI scan. Some subjects also underwent functional MRI. We calculated M1, primary sensory cortex, precuneus volumes, and total gray matter volume (TGMV) with FreeSurfer. The sensorimotor network (SMN) was identified using independent component analysis. The M1/precuneus ratio showed a significant difference between the NC and Prob/Def groups (p < 0.05). The diagnostic accuracy of the M1/precuneus ratio was moderate for distinguishing Prob/Def from NC (cutoff = 1.00, sensitivity = 0.42, specificity = 0.90). Two of eight cases without upper motor neuron dysfunction could be diagnosed with ALS using M1/precuneus ratio as a surrogate marker. A negative correlation between M1/precuneus ratio and functional activity was found in Brodmann area 6 in the SMN in all subjects. TGMV tended to decrease with disease progression (p = 0.04). The M1/precuneus volume ratio, associated with the SMN, may have potential as a surrogate biomarker of upper motor neuron dysfunction in ALS. Furthermore, TGMV may serve as an ALS disease-tracking biomarker.
(Keyword)
Humans / Amyotrophic Lateral Sclerosis / Retrospective Studies / Magnetic Resonance Imaging / Parietal Lobe / Motor Cortex / Biomarkers / Motor Neurons / Motor Neuron Disease
Shotaro Haji, Koji Fujita, Ryosuke Oki, Yusuke Osaki, Ryosuke Miyamoto, Hiroyuki Morino, Seiichi Nagano, Naoki Atsuta, Yuki Kanazawa, Yuki Matsumoto, Atsuko Arisawa, Hisashi Kawai, Yasutaka Sato, Satoshi Sakaguchi, Kenta Yagi, Tatsuto Hamatani, Tatsuo Kagimura, Hiroaki Yanagawa, Hideki Mochizuki, Manabu Doyu, Gen Sobue, Masafumi Harada and Yuishin Izumi : An Exploratory Trial of EPI-589 in Amyotrophic Lateral Sclerosis (EPIC-ALS): Protocol for a Multicenter, Open-Labeled, 24-Week, Single-Group Study, JMIR Research Protocols, Vol.12, e42032, 2023.
(Summary)
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder, with its currently approved drugs, including riluzole and edaravone, showing limited therapeutic effects. Therefore, safe and effective drugs are urgently necessary. EPI-589 is an orally available, small-molecule, novel redox-active agent characterized by highly potent protective effects against oxidative stress with high blood-brain barrier permeability. Given the apparent oxidative stress and mitochondrial dysfunction involvement in the pathogenesis of ALS, EPI-589 may hold promise as a therapeutic agent. This protocol aims to describe the design and rationale for the EPI-589 Early Phase 2 Investigator-Initiated Clinical Trial for ALS (EPIC-ALS). EPIC-ALS is an explorative, open-labeled, single-arm trial that evaluates the safety and tolerability of EPI-589 in patients with ALS. This trial consists of 12-week run-in, 24-week treatment, and 4-week follow-up periods. Patients will receive 500 mg of EPI-589 3 times daily over the 24-week treatment period. Clinical assessments include the mean monthly change of Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised total score. The biomarkers are selected to analyze the effect on oxidative stress and neuronal damage. The plasma biomarkers are 8-hydroxy-2'-deoxyguanosine (8-OHdG), 3-nitrotyrosine (3-NT), neurofilament light chain (NfL), phosphorylated neurofilament heavy chain (pNfH), homocysteine, and creatinine. The cerebrospinal fluid biomarkers are 8-OHdG, 3-NT, NfL, pNfH, and ornithine. The magnetic resonance biomarkers are fractional anisotropy in the corticospinal tract and N-acetylaspartate in the primary motor area. This trial began data collection in September 2021 and is expected to be completed in October 2023. This study can provide useful data to understand the characteristics of EPI-589. Japan Primary Registries Network jRCT2061210031; tinyurl.com/2p84emu6. DERR1-10.2196/42032.
Mayumi Takeuchi, Kenji Matsuzaki, Yoshimi Bando and Masafumi Harada : MR Imaging Findings of Uterine Adenomatoid Tumors., Magnetic Resonance in Medical Sciences, Vol.23, No.2, 127-135, 2023.
(Summary)
Adenomatoid tumor is a rare benign genital tract neoplasm of mesothelial origin. Uterine adenomatoid tumors occur in the outer myometrium and may mimic leiomyomas. Because hormonal treatment is not applicable to adenomatoid tumors and laparoscopic enucleation is not easy as myomectomy, it is important to differentiate adenomatoid tumors from leiomyomas for the adequate treatment. The purpose of this study is to evaluate the MRI findings of adenomatoid tumor for the differentiation from leiomyoma. MRI findings of surgically proven 10 uterine adenomatoid tumors in 9 women were retrospectively evaluated with correlation to histopathological findings. All 10 tumors appeared as solid myometrial masses and showed heterogeneous signal intensity with admixture of partially ill-defined slight high-intensity areas containing abundant tubular tumor cells and well-defined myoma-like low-intensity areas reflecting smooth muscle hypertrophy on T2WI including 4 lesions with peripheral ring-like high intensity. High-intensity areas on T2WI tended to show high intensity on diffusion-weighted imaging (DWI) with relatively high apparent diffusion coefficient (ADC), suggesting T2 shine-through effect due to abundant tubules. Intra-tumoral hemorrhage revealed on MRI was rare. Early intense contrast-enhanced areas on dynamic contrast-enhanced study were observed dominantly within the high-intensity areas but rarely within the low-intensity areas on T2WI. The outer myometrial mass with the admixture of well-defined low- and ill-defined high-intensity areas on T2WI may be suggestive of adenomatoid tumor. Peripheral ring-like high intensity on T2WI and DWI may also be suggestive. Dynamic contrast-enhanced MR study may be helpful for the differentiation from leiomyoma.
Yuki Kanazawa, KITANO Shun, Masafumi Harada, Yo Taniguchi, Yuki Matsumoto, Hiroaki Hayashi, Kosuke Ito, Yoshitaka Bito and Akihiro Haga : Myelin Water Atlas Template Derived from Quantitative Parameter Mapping, Proceedings of ISMRM, Vol.32, No.2630, 2023.
24.
Yuki Kanazawa, Tosiaki Miyati, Masafumi Harada, Mitsuharu Miyoshi, Yuki Matsumoto, Hiroaki Hayashi, Yasuhisa Kanematsu and Yasushi Takagi : Evaluation of Biological Metabolic Activity within an Atherosclerotic Plaque using Chemical Exchange Saturation Transfer Imaging, Proceedings of ISMRM, Vol.32, No.2982, 2023.
Taku Matsuda, Ryoma Morigaki, Yuki Matsumoto, Hideo Mure, Kazuhisa Miyake, Masahito Nakataki, Masafumi Harada and Yasushi Takagi : Obsessivecompulsive symptoms are negatively correlated with motor severity in patients with generalized dystonia, Scientific Reports, Vol.12, No.1, 20350, 2022.
(Summary)
We aimed to clarify the correlations between motor symptoms and obsessive-compulsive symptoms and between the volumes of basal ganglia components and obsessive-compulsive symptoms. We retrospectively included 14 patients with medically intractable, moderate and severe generalized dystonia. The Burke-Fahn-Marsden Dystonia Rating Scale and Maudsley Obsessional Compulsive Inventory were used to evaluate the severity of dystonia and obsessive-compulsive symptoms, respectively. Patients with generalized dystonia were divided into two groups; patients whose Maudsley Obsessional Compulsive Inventory score was lower than 13 (Group 1) and 13 or more (Group 2). Additionally, the total Maudsley Obsessional Compulsive Inventory scores in patients with dystonia were significantly higher than normal volunteers' scores (p = 0.025). Unexpectedly, Group 2 (high Maudsley Obsessional Compulsive Inventory scores) showed milder motor symptoms than Group 1 (low Maudsley Obsessional Compulsive Inventory scores) (p = 0.016). "Checking" rituals had a strong and significant negative correlation with the Burke-Fahn-Marsden Dystonia Rating Scale (ϱ = - 0.71, p = 0.024) and a strong positive correlation with the volumes of both sides of the nucleus accumbens (right: ϱ = 0.72, p = 0.023; left: ϱ = 0.70, p = 0.034). Our results may provide insights into the pathogenesis of obsessive-compulsive disorder and dystonia.
Takayoshi Shinya, Tomoki MATSUSHITA, Yuka HIROSHIMA, Youichi Otomi, Yasuhisa Kanematsu, Yoshimi Bando, Hisanori Uehara, Yoshiaki Kitamura and Masafumi Harada : Imaging features of a myoepithelial carcinoma of the nasal cavity: A case report and literature review, Radiology Case Reports, Vol.18, No.1, 386-391, 2022.
(Summary)
Myoepithelial carcinoma of the nasal cavity is extremely rare. We report the case of a 66-year-old man with myoepithelial carcinoma of the nasal cavity. Computed tomography (CT) and magnetic resonance imaging revealed a lobulated soft tissue mass with central necrosis and hemorrhage, as well as an invasion of the skull base and left orbit. The patient presented with continuous nasal congestion and heavy head and had no elevated level of squamous cell carcinoma-related antigen. CT, magnetic resonance imaging, or F-fluorodeoxyglucose (FDG) positron emission tomography/CT revealed no evidence of a metastatic lesion. F-FDG accumulation in the tumor was inhomogeneous and moderate. Histopathological examination of the resected specimen confirmed a well-circumscribed solid tumor with septa, a small area of hemorrhage, and necrosis. The subsequent diagnosis was a myoepithelial carcinoma of the left nasal cavity. This case shows that nasal myoepithelial carcinoma might appear as a well-defined lobulated mass with hemorrhagic necrosis and intense contrast enhancement in the solid component. We conjecture that hemorrhagic necrosis and intense enhancement values may be potential markers of nasal myoepithelial carcinoma.
Yuki Kanazawa, Masafumi Harada, Yo Taniguchi, Hiroaki Hayashi, Takashi Abe, Maki Ohtomo, Yuki Matsumoto, Masaharu Ono, Kosuke Ito, Yoshitaka Bito and Akihiro Haga : Myelin-weighted imaging derived from quantitative parameter mapping, European Journal of Radiology, Vol.156, No.110525, 1-9, 2022.
(Summary)
We developed a novel method which is applicable to visualize contrast according to myelin components in the human brain using relaxation time derived from quantitative parameter mapping magnetic resonance imaging (QPM-MRI). Using healthy volunteer data (n = 10), we verified that our method demonstrated that the myelin-weighted contrast increased proportionally by products R and R*, i.e., QPM-myelin-weighted image, in which modified T-weighted/T-weighted (Tw/Tw) ratio mapping method was applied. We compared measurement values in white matter (WM) and gray matter (GM) regions of the Tw/Tw ratio and R·R* product maps of healthy volunteers. Linear regression analysis between each value. Mann Whitney U test between WM and GM signals in each myelin map. In addition, Additionally, QPM-myelin-weighted image was applied to a 32-year-old female MS patient. Linear regression analysis showed a highly significant correlation between conventional Tw/Tw ratios and R·R* products derived from QPM (R = 0.73, P < 0.0001). Moreover, there is a significant difference between WM and GM structures in each myelin images (both, P < 0.0001). Additionally, in a clinical case, MS lesions enabled observation of not only MS plaques but also heterogeneous myelin signal loss associated with demyelination more clearly than Tw image and conventional Tw/Tw ratio image. Our myelin-weighted imaging technique using QPM may be useful for myelin visualization and is expected to become independent of measurement conditions due to having quantitative characteristics of QPM itself.
Mayumi Takeuchi, Kenji Matsuzaki, Yoshimi Bando and Masafumi Harada : Magnetic resonance imaging characteristics of polypoid endometriosis and review of the literature., The Journal of Obstetrics and Gynaecology Research, Vol.48, No.10, 2583-2593, 2022.
(Summary)
Polypoid endometriosis is a rare variant of endometriosis and may mimic malignancy. The purpose of this study is to evaluate magnetic resonance (MR) imaging characteristics of polypoid endometriosis for the differential diagnosis with malignancy. MR imaging findings of four histologically proven polypoid endometriosis were retrospectively evaluated with the review of the literature. All polypoid endometriosis exhibited high signal intensity on T2-weighted images reflecting abundant dilated endometrial glands. Peritoneal lesions were surrounded by low signal intensity rim represented the "black rim sign" reflecting endometriotic fibrous adhesion. Two cases arising from endometriotic cysts showed transmural extension (peritoneal extension and myometrial infiltration). Endometriotic hemorrhagic foci were demonstrated in four lesions as high signal intensity on T1-weighted images and/or susceptibility-induced signal voids on susceptibility-weighted MR sequence. Diffusion-weighted images showed high signal intensity with relatively high apparent diffusion coefficient (ADC) due to T2 shine-through effect but no diffusion restriction, and dynamic contrast-enhanced (DCE) MR imaging showed gradually increasing contrast-enhancement pattern like benign pathologies. Polypoid endometriosis may mimic malignancy; however, black rim sign may be a characteristic MR imaging finding for the peritoneal lesions, and no diffusion restriction and gradually increasing contrast-enhancement pattern may reflect its benign nature.
M Chuluunbat, D Matsuda, Koji Fujita, M Otomo, Youichi Otomi, K Kudo, Masafumi Harada and Yuishin Izumi : Identification and validation of a gray matter volume network in Alzheimer's disease, Journal of the Neurological Sciences, Vol.440, 120344, 2022.
(Summary)
This study aims to identify and validate a gray matter volume network in patients with Alzheimer's disease (AD). To identify a disease-related network, a principal component analysis-based algorithm, Scaled Subprofile Model, was applied to gray matter volume data derived from structural T1-weighted magnetic resonance imaging of the training sample that consisted of nine patients with AD (women, four; dementia, seven; mild cognitive impairment, two; age, 66.7 ± 8.8 [mean ± SD] years) with positive F-flutemetamol amyloid positron emission tomography and eight age-matched healthy controls obtained on-site. The network expression scores were calculated by topographic profile rating in the validation sample obtained via the Open Access Series of Imaging Studies and comprised 12 patients with AD dementia (women, four; age, 70.0 ± 3.7 years) and 12 age-matched healthy controls. A significant network from the training sample, for which subject expression differed between the groups (permutation test, P = 0.006; sensitivity and specificity, 100%; area under the curve, 1), was identified. This network was represented by the principal components 1, 2, and 3 and showed a relative decrease in the inferior parietal lobule including angular gyrus, inferior temporal gyrus, premotor cortex, amygdala, hippocampus, and precuneus. It significantly differed between the groups with a sensitivity, specificity, and area under the curve of 83%, 91%, and 0.85, respectively, in the validation sample (P = 0.003). An AD-related gray matter volume network that captured relevant regions was identified in amyloid positron emission tomography-positive patients and validated in an independent sample.
Natsuki Ikemitsu, Yuki Kanazawa, Masafumi Harada, Yuki Matsumoto, Hiroaki Hayashi, Kosuke Ito, Yo Taniguchi, Yoshitaka Bito and Akihiro Haga : Determination of white matter structure index for voxel basedmorphometry and connectivity analysis., European Congress of Radiology (EPOS), 10, 2022.
34.
Nagomi Fukuda, Yuki Kanazawa, Hiroaki Hayashi, Yuki Matsumoto, Masafumi Harada, Motoharu Sasaki and Akihiro Haga : Development of a B1 correction method without additional scanning VFA T1 map., European Congress of Radiology (EPOS), 10, 2022.
35.
Youichi Otomi, Saho Irahara, Hiroaki Inoue, Takayoshi Shinya, Hideki Otsuka and Masafumi Harada : Increased 18F-FDG Uptake in the Axillary Lymph Nodes of Vaccinated Side Associated with COVID-19 Vaccination, Molecular Imaging and Radionuclide Therapy, Vol.31, No.2, 169-171, 2022.
(Summary)
A 50-year-old female patient underwent (fluorine-fluorodeoxyglucose (F-FDG) positron emission tomography/computed tomography (PET/CT) following modified radical mastectomy for cancer of the left breast. Ten days before the PET/CT, the coronavirus disease-2019 (COVID-19) vaccine was injected intramuscularly into the right deltoid muscle. Increased (F-FDG uptake of maximum standardized uptake value (11.0) was observed in the lymph nodes of the right axilla, which had not been observed in the previous PET/CT. The size of the oval-shaped lymph nodes was up to approximately 11×9 mm; however, it was larger than that observed on the previous PET/CT. We contemplate that the increased (F-FDG uptake was a reactive change in the lymph nodes associated with the COVID-19 vaccine.
Mayumi Takeuchi, Kenji Matsuzaki, Yoshimi Bando and Masafumi Harada : Dynamic contrast-enhanced magnetic resonance imaging of endometrial cancer with/without squamous differentiation, Proc. Intl. Soc. Mag. Reson. Med., 4233, 2022.
37.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Susceptibility-weighted MR sequence for the evaluation of intra-tumoral hemorrhage: Differentiation of benign and malignant ovarian tumors, Proc. Intl. Soc. Mag. Reson. Med., 3673, 2022.
38.
Yuki Kanazawa, Masafumi Harada, Mitsuharu Miyoshi and Yuki Matsumoto : Evaluation of brain tumor and surrounding tissue activity using multi-pool CEST imaging on 3 Tesla scanner, Proceedings of ISMRM, Vol.31, No.4285, 2022.
39.
Nagomi Fukuda, Yuki Kanazawa, Hiroaki Hayashi, Yuki Matsumoto, Masafumi Harada, Motoharu Sasaki and Akihiro Haga : Development of self-calibrating B1 correction for three-dimensional variable flip angle T1 mapping, Proceedings of ISMRM, Vol.31, No.3218, 2022.
40.
Shun Kitano, Yuki Kanazawa, Masafumi Harada, Yo Taniguchi, Yuki Matsumoto, Hiroaki Hayashi, Kosuke Ito, Yoshitaka Bito and Akihiro Haga : Conversion map from quantitative parameter mapping to myelin water fraction, Proceedings of ISMRM, Vol.31, No.3052, 2022.
41.
Natsuki Ikemitsu, Yuki Kanazawa, Akihiro Haga, Hiroaki Hayashi, Yuki Matsumoto and Masafumi Harada : Determination of Alzheimer's disease based on morphology and atrophy using machine learning combined with automated segmentation., Proceedings of ISMRM, Vol.31, No.3263, 2022.
42.
Nahomi Shono, Youichi Otomi, Hideki Otsuka, Takayoshi Shinya and Masafumi Harada : Multicystic Biliary Hamartoma With Xanthogranulomatous Inflammation on 18F-FDG PET/CT., Clinical Nuclear Medicine, Vol.47, No.10, 882-884, 2022.
(Summary)
A 70-year-old man with a liver tumor was pathologically diagnosed with multicystic biliary hamartoma with xanthogranulomatous inflammation. Plain CT revealed an inhomogeneous low-density liver tumor, measuring 43 × 35 mm. Dynamic contrast-enhanced CT revealed a cyst, measuring approximately 15 mm, with a ring-shaped enhancement, within the tumor. There was delayed enhancement on the outer portion of the tumor. Mild peripheral bile duct dilation was also observed. 18F-FDG PET/CT showed focal high uptake with an SUVmax of 5.2 near the cyst. The findings of this case mimicked that of intrahepatic cholangiocellular carcinoma.
Shoichiro Takao, Maho Kaneda, Mihoko Sasahara, Suzuka Takayama, Yoshitaka Matsumura, Tetsuya Okahisa, Tsuyoshi Goto, Nori Sato, Shinsuke Katoh, Masafumi Harada and Junji Ueno : Diffusion tensor imaging (DTI) of human lower leg muscles: correlation between DTI parameters and muscle power with different ankle positions., Japanese Journal of Radiology, 2022.
(Summary)
DTI parameters were significantly changed depending on the ankle joint position and type of muscle contraction.
Yoshiteru Tada, Toshitaka Fujihara, Kenji Shimada, Nobuaki Yamamoto, Hiroki Yamazaki, Yuishin Izumi, Masafumi Harada, Yasuhisa Kanematsu and Yasushi Takagi : Seizure types associated with negative arterial spin labeling and positive diffusion-weighted imaging on peri-ictal magnetic resonance imaging, Journal of the Neurological Sciences, Vol.436, 1-8, 2022.
(Summary)
Arterial spin labeling (ASL) and diffusion-weighted imaging (DWI) are useful for assessing hyperperfusion and cytotoxic edema, respectively, caused by acute seizures. This study investigated the clinical characteristics associated with normal ASL findings and DWI abnormalities in patients with acute seizures. Overall, 41 patients with ASL and DWI images that were obtained within 48 h of focal onset seizure diagnosis, due to epilepsy or acute symptomatic seizures, were divided into groups based on initial ASL findings (ASL-negative vs. ASL-positive), and DWI abnormalities (DWI-negative vs. DWI-positive). The diagnosis was made based on seizure semiology, electroencephalography, and conventional imaging modalities. ASL and DWI abnormalities were based on visual assessment. Of the 41 patients, eight (19.5%) displayed normal ASL findings. The proportion of patients with focal aware seizures (FAS) was significantly higher among ASL-negative patients (62.5%) than that in ASL-positive patients (15.2%); the proportion of patients with focal impaired awareness seizures (FIAS) was significantly lower among ASL-negative patients (12.5%) than that among ASL-positive patients (57.6%). Hyperintensity findings on DWI were observed in 12 patients (29.3%, DWI-positive). The proportion of patients with FIAS was significantly higher among DWI-positive patients (75.0%) than that among DWI-negative patients (37.9%). Multivariate analysis revealed that FAS and FIAS were associated with normal ASL findings (odds ratio [OR]: 21.37, P = 0.010) and DWI abnormalities (OR = 6.11, P = 0.028). A diagnosis of seizures should not be excluded based on normal ASL findings, especially in patients with FAS. FIAS may be a risk factor for neuronal damage caused by seizure activity.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Yo Taniguchi, Masaharu Ono and Yoshitaka Bito : Quantitative parameter mapping of contrast agent concentration and relaxivity and brain tumor extracellular pH, Scientific Reports, 2022.
(Summary)
In clinical magnetic resonance imaging, gadolinium-based contrast agents are commonly usedfor detecting brain tumors and evaluating the extent of malignancy. We present a new method toevaluate relaxivity (r1) and contrast agent concentration separately in contrast-enhanced lesions usingquantitative parameter mapping (QPM). Furthermore, we also aimed to estimate the extracellularpH (pHe) of tumor lesions. We demonstrated that it is possible to evaluate pathophysiological tumorchanges due to therapeutic efficacy by measuring r1 in contrast-enhanced lesions. In this study, theprimary brain tumor group showed significantly higher r1 values than other brain disease groups(P< 0.001). Moreover, mean pHe value showed a trend for tumor malignancy having a lower pHevalue and primary brain tumor having a significantly lower pHe than other brain diseases (P< 0.001).Our results might suggest that QPM can separately quantify r1 and CA concentration in brain tumorsand that pHe brain tumor mapping could serve as a tumor biomarker. In conclusion, our method haspotential clinical applications for assessing the treatment effects.
Youichi Otomi, Yuta Arai, Maki Ohtomo, Saho Irahara, Kaori Terazawa, Michiko Kubo, Takashi Abe, Takayoshi Shinya, Hideki Otsuka and Masafumi Harada : Increased physiological [18F] FDG uptake in the liver and blood pool among patients with impaired renal function, Nuclear Medicine Review. Central & Eastern Europe, Vol.25, No.2, 95-100, 2022.
(Summary)
In the daily clinical course, the liver uptake may seem to be increased in patients with renal failure. The purpose of this study was to investigate whether or not the FDG uptake of the liver, and the FDG uptake of blood pool which is generally used as a reference site as well as liver, is increased in patients with renal failure. We retrospectively analyzed 233 patients who underwent FDG positron emission tomography/computed tomography (PET/CT). Renal failure is defined as an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2. We compared the FDG uptake in the liver and mediastinal blood pool of 67 patients with impaired renal function to that in 166 patients with a normal renal function (eGFR ≥ 60 mL/min/1.73 m2). Correlations between the liver or mediastinal blood pool FDG uptake and the eGFR were also analyzed by Spearman's correlation test. Maximum and mean standardized uptake values (SUVmax and SUVmean, respectively) of the liver and the SUVmean of the mediastinal blood pool were 3.48 ± 0.57, 2.56 ± 0.37, and 1.90 ± 0.28 in the impaired renal function group, respectively, and 3.13 ± 0.45, 2.29 ± 0.33, and 1.66 ± 0.23, in the normal group, respectively. The SUVmax and SUVmean of the liver and SUVmean of the mediastinal blood pool in the impaired renal function group were significantly higher than those in the normal group (p < 0.001, < 0.001, and < 0.001, respectively). The SUVmax and SUVmean of the liver and SUVmean of the mediastinal blood pool of patients showed a significant negative correlation with the eGFR (Spearman's p = -0.25, -0.30, and -0.40, respectively, each p < 0.001). FDG uptake in both the liver and mediastinal blood pool was higher in patients with impaired renal function.
Madoka Kohno, ANAYT ULLA, Rina Taniguchi, Akane Ohishi, Kako Hirayama, Yuma Takemura, Shoichiro Takao, Yuki Kanazawa, Yuki Matsumoto, Masafumi Harada, Tomoya Fukawa, Hiro-omi Kanayama, Takayuki Uchida, Toshio Suzuki and Takeshi Nikawa : Daily Dietary Supplementation with Steamed Soybean Improves Muscle Volume and Strength in Healthy People Lacking Exercise., Journal of Nutritional Science and Vitaminology, Vol.68, No.6, 521-526, 2022.
(Summary)
Various dietary protein supplements are used by the elderly and bedridden to maintain their skeletal muscle mass and functions. High-quality proteins act as an anabolic driver and help to improve muscle strength and performance. Previously, we reported that soy protein significantly attenuates denervation-induced loss of muscle mass and myofiber cross sectional area in mice with inhibition of ubiquitination and degradation of IRS-1 in tibialis anterior muscle. It also increased muscle volume and strength in bedridden patients. In the present study, we investigated the effects of dietary soybean supplementation on muscle functions in taxi drivers lacking vigorous physical exercise. We conducted a case-control study on 25 healthy, male taxi drivers between the ages of 36 and 71 y performing minimal physical exercise. They were divided into two dietary groups: the soybean diet group (n=13) who ate daily meals (dinner) supplemented with 50 g of steamed soybean for 30 d and the control diet group (n=12) who received no soybean supplement. Next, we measured the muscle cross-sectional area (CSA) and muscle strength and function in both the groups before and after 30 d of soybean intake. The body weights of both diet groups did not differ significantly over time. However, after 30 d of soybean supplementation, the soybean-fed group developed significantly higher muscle CSA and grip strength compared to the control groups. In conclusion, dietary soybean supplementation improved muscle function in taxi drivers who lacked exercise.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : The feasibility of reduced field-of-view diffusion-weighted imaging in evaluating bladder invasion of uterine cervical cancer., The British Journal of Radiology, Vol.Online ahead of print, 20210692, 2021.
(Summary)
Objectives: Uterine cervical cancer with bladder mucosal invasion is classified as FIGO stage IVA with poor prognosis. MRI can rule out the bladder invasion and skipping cystoscopy may be possible; however, high false-positive rate may be problematic. The purpose of this study is to evaluate the diagnostic performance of reduced field-of-view (FOV) diffusion-weighted imaging (DWI) in evaluating bladder mucosal invasion of cervical cancer. Methods: 3T MRI including T2WI and reduced FOV DWI in 15 women with histologically proven cervical cancer (two stage IIIB, six stage IVA, seven stage IVB) were retrospectively evaluated compared with cystoscopic findings. Results: Cystoscopy revealed mucosal invasion in 13 of 15 cases. The border between the tumor and the bladder wall was unclear on T2WI and clear on reduced FOV DWI in all 15 cases. The diagnosis of mucosal invasion on reduced FOV DWI had a sensitivity of 100%, specificity of 50%, accuracy of 93%, PPV of 93%, and NPV of 100%. Conclusions: Addition of reduced FOV DWI may improve the staging accuracy of MRI for cervical cancer in assessing the bladder mucosal invasion. Advances in knowledge: Reduced FOV DWI may improve the staging accuracy of cervical cancer in assessing bladder mucosal invasion with high NPV and PPV, which may be helpful for avoiding unnecessary cystoscopy.
Moriaki Yamanaka, Shoichiro Takao, Hideki Otsuka, Youichi Otomi, Saho Irahara, Yamato Kunikane, Satoru Takashi, Airi Yamamoto, Masataka Sata and Masafumi Harada : The Utility of a Combination of <sup>99m</sup>Tc-MIBI Washout Imaging and Cardiac Magnetic Resonance Imaging in the Evaluation of Cardiomyopathy, Annals of Nuclear Cardiology, Vol.7, No.1, 8-16, 2021.
(Summary)
Background: In cardiomyopathy, 99mTc-MIBI washout can reflect mitochondrial dysfunction and late gadolinium enhancement (LGE) on cardiac magnetic imaging (MRI) is associated with tissue fibrosis. We sought to determine the relationship between 99mTc-MIBI uptake, 99mTc-MIBI washout, and LGE on MRI in patients with cardiomyopathy. Methods: Twenty-one patients underwent rest myocardial perfusion scintigraphy at 45 minutes (early) and 4 hours (delayed) after intravenous 99mTc-MIBI administration and cardiac MRI. We assessed myocardial perfusion, 99mTc-MIBI washout, and LGE. We divided the left ventricle (LV) wall into 16 segments using a polar map. Then, we classified each segment into 5 groups according to 99mTc-MIBI uptake in early-rest images and washout. Additionally, we created a contingency table based on LGE presence/absence in the groups. Results: We evaluated 336 segments in 21 patients. 99mTc-MIBI uptake was decreased in 168 segments in the early-rest 99mTc-MIBI images. 99mTc-MIBI washout was observed in 108 segments with either normal perfusion or reduced perfusion in the early-rest 99mTc-MIBI images. LGE was positive in 104 segments. A contingency table analysis with Fisher窶冱 exact test showed that LGE was observed significantly more frequently in the segments with decreased 99mTc-MIBI uptake (p < 0.001). In segments without a decreased 99mTc-MIBI uptake, there was a significant correlation between increased 99mTc-MIBI washout and the presence of LGE (p = 0.033). Conclusions: In cardiomyopathy, the mitochondrial dysfunction in the early stage is shown as 99mTc-MIBI washout, and fibrotic changes in the myocardium in advanced stages are shown as LGE on cardiac MRI. The severity of myocardial damage and the clinical stage of cardiomyopathy can be evaluated using multimodal imaging.
(Keyword)
<sup>99m</sup>Tc-MIBI / Cardiomyopathy / Late gadolinium enhancement (LGE) / Washout
T Fukumoto, Ryosuke Miyamoto, Koji Fujita, Masafumi Harada and Yuishin Izumi : Gait apraxia as a presenting sign of Gerstmann-Sträussler-Scheinker disease, Neurology and Clinical Neuroscience, Vol.9, No.4, 339-341, 2021.
Wataru Sako, T Abe, Y Matsumoto, K Nakamura, Shotaro Haji, Yusuke Osaki, Masafumi Harada and Yuishin Izumi : The cerebellum is a common key for visuospatial execution and attention in Parkinson's disease, Diagnostics, Vol.11, No.6, 1042, 2021.
(Summary)
Cognitive decline affects the clinical course in patients with Parkinson's disease (PD) and contributes to a poor prognosis. However, little is known about the underlying network-level abnormalities associated with each cognitive domain. We aimed to identify the networks related to each cognitive domain in PD using resting-state functional magnetic resonance imaging (MRI). Forty patients with PD and 15 normal controls were enrolled. All subjects underwent MRI and the Mini-Mental State Examination. Furthermore, the cognitive function of patients with PD was assessed using the Montreal Cognitive Assessment (MoCA). We used independent component analysis of the resting-state functional MRI for functional segmentation, followed by reconstruction to identify each domain-related network, to predict scores in PD using multiple regression models. Six networks were identified, as follows: the visuospatial-executive-domain-related network ( = 0.54, < 0.001), naming-domain-related network ( = 0.39, < 0.001), attention-domain-related network ( = 0.86, < 0.001), language-domain-related network ( = 0.64, < 0.001), abstraction-related network ( = 0.10, < 0.05), and orientation-domain-related network ( = 0.64, < 0.001). Cerebellar lobule VII was involved in the visuospatial-executive-domain-related and attention-domain-related networks. These two domains are involved in the first three listed nonamnestic cognitive impairment in the diagnostic criteria for PD with dementia (PDD). Furthermore, Brodmann area 10 contributed most frequently to each domain-related network. Collectively, these findings suggest that cerebellar lobule VII may play a key role in cognitive impairment in nonamnestic types of PDD.
Mika Takahashi, Gou Satou, Naoki Toda, Takahiro Azuma, Katsuhiko Nakamura, Hidetaka Iwasaki, Hitomi Miyoshi, Kazunori Matsuda, Yoshiaki Kitamura, Koji Abe, Shoichiro Takao, Masafumi Harada and Noriaki Takeda : Vestibular and cochlear nerve enhancement on MRI and its correlation with vestibulocochlear functional deficits in patients with Ramsay Hunt syndrome., Auris, Nasus, Larynx, Vol.48, No.3, 347-352, 2021.
(Summary)
In patients with RHS, the origin of vertigo may be superior vestibular neuritis, which is affected by reactive varicella-zoster virus from the geniculate ganglion of the facial nerve through the faciovestibular anastomosis. The results also suggested that in some RHS patients, inferior vestibular neuritis contributes to the development of vertigo and that the origin of refractory sensorineural hearing loss is cochlear neuritis.
Tamaki Otani, Hideki Otsuka, Kou Matsushita, Yoichi Otomi, Yamato Kunikane, Shota Azane, Masafumi Amano, Masafumi Harada and Hirokazu Miyoshi : Effect of different examination conditions on image quality and quantitative value of amyloid positron emission tomography using F-flutemetamol., Annals of Nuclear Medicine, Vol.35, No.9, 1004-1014, 2021.
(Summary)
The recommended start time for F-flutemetamol amyloid positron emission tomography (PET) examination is 60-120 min after F-flutemetamol injection, while an acquisition time of 10-30 min is generally recommended. We aimed to elucidate the effects of different examination conditions on image quality, diagnostic ability, and quantitative value of amyloid PET using F-flutemetamol. We acquired data on a Discovery PET/computed tomography 710 scanner using Hoffman brain and pillar phantoms with 20 MBq of F for 30 min. The images were reconstructed into 10-, 20-, and 30-min periods. The ordered subset-expectation maximization algorithm was used for image reconstruction, which uses a 2- or 4-mm Gaussian filter and a combination of iteration and subset numbers. The percentage contrast and coefficient of variation (CV; as the image noise) were used as physical evaluation indices for reconstructed images, and images with superior contrast and low image noise were selected for clinical evaluation. The imaging data of 15 symptomatic patients (n = 7 and n = 8 for positive and negative diagnoses of Alzheimer's disease, respectively) were reconstructed under the phantom study conditions. Radiographers visually evaluated and ranked the clinical images based on the overall contrast and image noise, and nuclear medicine specialists diagnosed Alzheimer's disease. We compared the standardized uptake value ratio (SUVR) obtained with different acquisition conditions. The basic study using the phantom revealed high convergence of contrast and image noise in five patterns of acquisition time and filter strengths. Regarding visual evaluation, the use of a 2-mm Gaussian filter caused difficulties in diagnosis because the brain parenchymal accumulation was mottled with high image noise. Differences in image quality and diagnostic ability due to different examination times were not significant. Differences in the SUVR were not significant in patients with a negative Alzheimer's disease diagnosis; in patients with a positive diagnosis, the SUVR showed significant fluctuation depending on the acquisition conditions. The differences in image quality and diagnostic performance due to the differences in 10-min acquisition time were not significant; however, of note, SUVR showed significant fluctuation depending on the acquisition conditions in patients diagnosed with Alzheimer's disease.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Uterine cervical adenocarcinomas associated with lobular endocervical glandular hyperplasia: MR imaging manifestations, Proc. Intl. Soc. Mag. Reson. Med., 3873, 2021.
56.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : The feasibility of reduced field-of-view DWI in evaluating bladder invasion of uterine cervical cancery, Proc. Intl. Soc. Mag. Reson. Med., 3875, 2021.
57.
Kohei Muto, Ryosuke Miyamoto, Yuka Terasawa, Yoshimitsu Shimatani, Keijiro Hara, Takumi Kakimoto, Tatsuya Fukumoto, Yusuke Osaki, Koji Fujita, Masafumi Harada, Hisanori Uehara, Yasushi Takagi and Yuishin Izumi : A novel COL4A1 variant associated with recurrent epistaxis and glioblastoma, Human Genome Variation, Vol.8, No.1, 18, 2021.
Naoki Maeda, Yuki Kanazawa, Masafumi Harada, Yo Taniguchi, Yuki Matsumoto, Hiroaki Hayashi, Kosuke Ito, Yoshitaka Bito and Akihiro Haga : Derivation of Water Exchange Constants between Components using Quantitative Parameter Mapping (QPM), Proceedings of ISMRM, Vol.29, No.3069, 2021.
59.
Yusuke Osaki, Wataru Sako, Masafumi Harada and Yuishin Izumi : Magnetic resonance tractography exhibiting retrograde degeneration of the corticospinal tract in a patient with a unilateral spinal cord tumor, Brain and Behavior, Vol.11, No.4, e02020, 2021.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Clinical value of N-acetyl mucinous compounds and lipid peaks in differentiating benign and malignant ovarian mucinous tumors by MR spectroscopy., Clinical Imaging, Vol.78, 127-135, 2021.
(Summary)
Purpose: To retrospectively evaluate the clinical significance of the peaks of N-acetyl mucinous compounds (NAMC) at 2 ppm and lipid at 1.3 ppm in in-vivo proton magnetic resonance (MR) spectroscopy for distinguishing benign and malignant mucinous tumors in patients with ovarian masses. Methods: MR spectroscopy was performed in patients with pathologically diagnosed mucinous ovarian tumors at 3 T MRI system. The peaks of NAMC, lipid, and total choline compounds (tCho) were classified into three classes in comparison with the noise level by visual estimation. The NAMC concentration was quantified relative to unsuppressed water by using LCModel analysis. Results: A total of 27 ovarian mucinous tumors in 27 patients were included in this study. The NAMC peak was observed in all 27 mucinous tumors, and the lipid peak was observed in 14 of 27 tumors: 1 of 9 benign tumors (11%), and 13 of 18 malignant tumors (11 borderline malignancies and 7 carcinomas) (72%). The presence of the lipid peak for the diagnosis of malignant mucinous tumor showed generally better diagnostic ability than MR imaging, with a sensitivity of 72%, specificity of 89%, accuracy of 78%, PPV of 93%, and NPV of 62%. The concentration of the NAMC in malignant mucinous tumors tended to be higher than that in benign mucinous tumors, but there was no statistically significant difference. Conclusions: The bimodal peaks of NAMC and lipid are suggestive of malignant mucinous tumors, and the presence of the lipid peak may be useful in distinguishing benign from malignant ovarian mucinous tumors.
Ryota Bando, Hideki Otsuka, Tamaki Otani, Noritake Matsuda, Shota Azane, Yamato Kunikane, Yoichi Otomi, Wataru Sako, Yuishin Izumi and Masafumi Harada : A new quantitative index in the diagnosis of Parkinson syndrome by dopamine transporter single-photon emission computed tomography., Annals of Nuclear Medicine, Vol.35, No.4, 504-513, 2021.
(Summary)
Dopamine transporter single-photon emission computed tomography (DAT SPECT) has been widely used to diagnose Parkinson syndrome. Using the standardized uptake value (SUV) of DAT SPECT, we propose "functional dopamine transporter volume (f-DTV)" as a new quantitative index to evaluate the three-dimensional volume of functional dopamine transporters and assess its diagnostic ability in differentiating dopaminergic neurodegenerative diseases (dNDD) from non-dNDD. Seventy-nine patients were enrolled (42 dNDD, 37 non-dNDD; 38 men; age 24-88 years). We analyzed seven quantitative indices. The specific binding ratio (SBR) was calculated using a program specialized for DAT SPECT (SBR_Bolt). The SUVmax, SUVpeak, and SUVmean were calculated using a quantification program for bone SPECT. SBR_SUV was calculated by dividing striatal SUVmean by the average of background SUVmean. The cutoff value of the active dopamine transporter level was examined using three methods (threshold of 40% of SUVmax, SUV 2, and SUV 3) to calculate the active dopamine transporter volume (ADV). The f-DTV was calculated by multiplying ADV and SUV. We assessed the correlations between SBR_Bolt and SBR_SUV, and compared the mean value of each index between the dNDD and non-dNDD groups. The abilities of SBR_Bolt, SBR_SUV, SUVmax, SUVpeak, SUVmean, ADV, and f-DTV in differentiating dNDD from non-dNDD were determined by the area under the receiver operating curve (AUC) generated by the receiver operating characteristics analysis. The SBR_Bolt and SBR_SUV highly correlated with each other (r = 0.71). The cutoff value of the active dopamine transporter level was determined as SUV 3. All seven quantitative indices showed lower values in the dNDD group than in the non-dNDD group, and the difference between the two groups was statistically significant (p < 0.05). Sensitivity, specificity, and AUC of f-DTV were slightly lower than those of SBR_Bolt (71%, 79%, and 0.81, respectively, for f-DTV, and 81%, 84%, 0.88, respectively, for SBR_Bolt). The difference in AUC between f-DTV and SBR_Bolt was not statistically significant. This study demonstrates the utility of f-DTV as a novel quantitative index for evaluating the three-dimensional volume of functional dopamine transporters, and that f-DTV has almost the same diagnostic ability to differentiate dNDD from non-dNDD using DAT SPECT.
(Keyword)
Adult / Aged / Aged, 80 and over / Biological Transport / Diagnosis, Differential / Dopamine Plasma Membrane Transport Proteins / female / Humans / Iodine Radioisotopes / male / Middle Aged / Nortropanes / Parkinson's disease / Phantoms, Imaging / ROC Curve / Retrospective Studies / Tomography, Emission-Computed, Single-Photon
Youichi Otomi, Nahomi Shono, Hajime Onishi, Ryota Mitsuhashi, Saya Matsuzaki, Yukiko Takaoka, Hideaki Enomoto, Yuko Sakamoto, Mihoko Sasahara, Takashi Abe, Takayoshi Shinya, Hideki Otsuka and Masafumi Harada : A reduced physiological 18 F-fluorodeoxyglucose uptake in the brain and liver caused by malignant lymphoma being deprived of the tracer, The Journal of Medical Investigation : JMI, Vol.68, No.1. 2, 181-185, 2021.
(Summary)
Purpose : To investigate whether or not the physiological brain and liver FDG uptake are decreased in patients with highly accelerated glycolysis lesions. Methods : We retrospectively analyzed 51 patients with malignant lymphoma. We compared the FDG uptake in the brain and liver of the patients with that in a control group. In 24 patients with a complete response (CR) or partial response (PR) to treatment, we compared the brain and liver uptake before and after treatment. Results : The maximum standardized uptake value (SUVmax) and total glycolytic volume (TGV) of the brain as well as the SUVmax and mean standardized uptake value (SUVmean) of the liver in malignant lymphoma patients were 13.1 ± 2.3, 7386.3 ± 1918.4, 3.2 ± 0.5, and 2.3 ± 0.4, respectively ; in the control group, these values were 14.9 ± 2.4, 8566.2 ± 1659.5, 3.4 ± 0.4, and 2.5 ± 0.3, respectively. The SUVmax and TGV of the brain and the SUVmean of the liver in malignant lymphoma patients were significantly lower than the control group. The SUVmax and TGV of the brain after treatment were significantly higher than before treatment. Both the SUVmax and SUVmean of liver after treatment were higher than before treatment, but not significant. Conclusion : A decreased physiological brain and liver FDG uptake is caused by highly accelerated lesion glycolysis. J. Med. Invest. 68 : 181-185, February, 2021.
Takayoshi Shinya, Otomi Yoichi, Toshihiko Nishisho, B Beuthien-Baumann, Saho Irahara, Michiko Kubo, Hideki Otsuka, Yoshimi Bando, Koichi Sairyo and Masafumi Harada : Clinical application of dynamic 18F-fluorodeoxyglucose positron-emission tomography / computed tomography in the differential diagnoses of musculoskeletal lesions, The Journal of Medical Investigation : JMI, Vol.68, No.1. 2, 96-104, 2021.
(Summary)
<p>We aimed to assess the differential diagnostic efficacy of dynamic F-18 fluorodeoxyglucose (FDG) positron emission tomography / computed tomography (PET / CT) and to evaluate the appropriate scan timings for diagnosis of musculoskeletal lesions (MSLs). Dynamic scans (5-15 [phase 1], 15-25 [phase 2], and 25-35 [phase 3] min after F-18 FDG injection) and dual-time-point scans (1 and 2 h after injection) were acquired for 23 MSLs [4 benign MSLs (BMSLs). 10 primary malignant musculoskeletal tumors (PMMSTs), and 9 metastatic musculoskeletal tumors (MMSTs)]. We compared the maximum standardized uptake values (SUVmax) and corresponding retention indices for dynamic (RI-SUVdyn) and dual-time-point (RI-SUVdual) scans and evaluated diagnostic efficacy using receiver operating characteristic (ROC) curve analyses. The SUVmax gradually decreased or was almost identical with minimal fluctuation in 3 BMSLs and 1 PMMST. SUVmax increased over time after phase 2 in 18 malignant MSLs (MMSLs). There were significant differences in SUVmax (for all time phases) and RI-SUV dual between BMSLs and MMSLs and between PMMSTs and MMSTs. In the ROC analyses, the areas under the curve for SUV in phases 2 and 3 were highest for differentiating BMSLs from MMSLs and PMMSTs from MMSTs, respectively. Dynamic F-18 FDG PET / CT is valuable for diagnosis of musculoskeletal lesions. J. Med. Invest. 68 : 96-104, February, 2021</p>
(Keyword)
bone and soft tissue tumors / dynamic scan / musculoskeletal lesion / positron emission tomography computed tomography / sarcoma
Takayoshi Shinya, Youichi Otomi, Toshihiko Nishisho, Bettina Beuthien-Baumann, Michiko Kubo, Hideki Otsuka, Yoshimi Bando, Hiroaki Yanagawa, Koichi Sairyo and Masafumi Harada : Preliminary clinical assessment of dynamic carbon-11 methionine positron-emission tomography/computed tomography for the diagnosis of the pathologies in patients with musculoskeletal lesions: a prospective study., European Journal of Hybrid Imaging, Vol.26, No.4, 15, 2020.
(Summary)
Dynamic C-11 MET PET scans have the potential to be good predictors of discriminating MSLs in patients with primary unknown MSLs in clinical practice.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : MRI findings of uterine adenomatoid tumors including diffusion-weighted imaging with pathologic correlation, Proc. Intl. Soc. Mag. Reson. Med., Vol.28, 6111, 2020.
66.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Clinical value of N-acetyl mucinous compounds and lipid peaks in differentiating benign and malignant ovarian mucinous tumors by MR spectroscopy, Proc. Intl. Soc. Mag. Reson. Med., Vol.28, 6278, 2020.
67.
Ikuho Kosaka, Yuki Kanazawa, Kotaro Baba, Hiroaki Hayashi and Masafumi Harada : Quantitative analysis of vibration waves based on Fourier transform in magnetic resonance elastography, Radiological Physics and Technology, Vol.13, 268-275, 2020.
(Summary)
We developed a novel magnetic resonance elastography (MRE) analysis method based on Fourier transform to assess the responsive characteristics for different tissue stiffness and degree of transmission of the vibration wave emanating from a passive driver during MRE. A phantom tissue study was conducted with an MRE sequence and vibration wave system using a clinical MR scanner. The phantom tissue consisted of two layers of agar: 0.75 wt% and 1.0 wt%. Phase-unwrapped images derived from acquired MRE phase images were used to generate a phase profile curve, with a line plotted for the phase-unwrapped images. Fourier transform was performed, and the peak value of the power spectrum was derived. The damping rate/ratio was calculated using the Hilbert transform of the phase profile. We found that the mean shear stiffness value of 1.0 wt% agar was higher than that of 0.75 wt% agar. The responsive frequency of the 0.75 wt% agar layer showed a wider range and the damping rate of the signal showed a higher value than the respective values of the 1.0 wt% agar layer. In conclusion, Fourier transform analysis of MRE enabled us to obtain more detailed information of the tissue characteristics and vibration-wave conditions.
Maki Ohtomo, Masafumi Harada, Takashi Abe, Yuki Matsumoto, Yumi Abe, Yuki Kanazawa, Mitsuharu Miyoshi, Hiroyuki Kabasawa and Yoshitake Takahashi : Reproducibility and Variability of Quantitative Cerebral Blood Flow Measured by Multi-delay 3D Arterial Spin Labeling According to Sex and Menstrual Cycle, The Journal of Medical Investigation : JMI, Vol.67, No.3.4, 321-327, 2020.
(Summary)
Purpose : To determine the reproducibility of corrected quantitative cerebral blood flow (qCBF) through measurement of transit flow time using multi-delay three-dimensional pseudo-continuous arterial spin labeling (pCASL) in healthy men and women and to evaluate the differences in qCBF between not only men and women, but also the follicular and luteal phases of the women's menstrual cycle. Methods : The participants were 16 healthy volunteers (8 men and 8 women ; mean age, 25.3 years). Two MRI were conducted for all participants ; female participants were conducted in the follicular and luteal phases. The reproducibility of qCBF values was evaluated by the intraclass correlation coefficient (ICC) and differences between the two groups were estimated by voxel-based morphometry (VBM) analysis. Results : The qCBF values were lower in men than in women, and those in females were significantly different between the follicular and luteal phases (P < 0.05). In VBM analysis, the qCBF values of the lower frontal lobes were significantly higher in women than in men (P < 0.05). The qCBF values of the frontal pole were significantly higher in the follicular phase than in the luteal phase (P < 0.01). Conclusion : Multi-delay pCASL can reveal physiological and sex differences in cerebral perfusion. J. Med. Invest. 67 : 321-327, August, 2020.
Yuki Kanazawa, Masafumi Harada, Mitsuharu Miyoshi, Takashi Abe, Yuki Matsumoto and Yasushi Takagi : Characterization of Brain Tumors using Amide Proton and Nuclear Overhauser Effect at 3 Tesla MR Scanner, Proceedings of the 28th Virtual Conference of ISMRM, No.1697, 2020.
70.
Yuki Kanazawa, Masafumi Harada, Tosiaki Miyati, Takashi Abe, Mitsuharu Miyoshi, Yuki Matsumoto, Hiroaki Hayashi, Yasuhisa Kanematsu and Yasushi Takagi : Chemical Exchange Saturation Transfer Imaging for Atherosclerotic Plaques, Proceedings of 28th Virtual Meeting of ISMRM, No.2128, 2020.
71.
Shotaroh Yoshioka, Takeshi Miyamoto, Junichiro Satomi, Yoshiteru Tada, Kenji Yagi, Kenji Shimada, Koji Naruishi, Eiji Shikata, Izumi Yamaguchi, Tadashi Yamaguchi, Masaaki Korai, Yoshihiro Okayama, Masafumi Harada, Keiko Kitazato, Yasuhisa Kanematsu, Shinji Nagahiro and Yasushi Takagi : Disequilibrium of Plasma Protease/Anti-Protease Due to Severe Periodontal Disease Contributes to Human Subarachnoid Hemorrhage, Neurosurgery Open, Vol.1, No.3, 1-9, 2020.
Kenya Kusunose, Takashi Abe, Akihiro Haga, Daiju Fukuda, Hirotsugu Yamada, Masafumi Harada and Masataka Sata : A Deep Learning Approach for Assessment of Regional Wall Motion Abnormality From Echocardiographic Images, JACC. Cardiovascular Imaging, Vol.13, No.2, 374-381, 2020.
(Summary)
This study investigated whether a deep convolutional neural network (DCNN) could provide improved detection of regional wall motion abnormalities (RWMAs) and differentiate among groups of coronary infarction territories from conventional 2-dimensional echocardiographic images compared with that of cardiologists, sonographers, and resident readers. An effective intervention for reduction of misreading of RWMAs is needed. The hypothesis was that a DCNN trained using echocardiographic images would provide improved detection of RWMAs in the clinical setting. A total of 300 patients with a history of myocardial infarction were enrolled. From this cohort, 3 groups of 100 patients each had infarctions of the left anterior descending (LAD) artery, the left circumflex (LCX) branch, and the right coronary artery (RCA). A total of 100 age-matched control patients with normal wall motion were selected from a database. Each case contained cardiac ultrasonographs from short-axis views at end-diastolic, mid-systolic, and end-systolic phases. After the DCNN underwent 100 steps of training, diagnostic accuracies were calculated from the test set. Independently, 10 versions of the same model were trained, and ensemble predictions were performed using those versions. For detection of the presence of WMAs, the area under the receiver-operating characteristic curve (AUC) produced by the deep learning algorithm was similar to that produced by the cardiologists and sonographer readers (0.99 vs. 0.98, respectively; p = 0.15) and significantly higher than the AUC result of the resident readers (0.99 vs. 0.90, respectively; p = 0.002). For detection of territories of WMAs, the AUC by the deep learning algorithm was similar to the AUC by the cardiologist and sonographer readers (0.97 vs. 0.95, respectively; p = 0.61) and significantly higher than the AUC by resident readers (0.97 vs. 0.83, respectively; p = 0.003). From a validation group at an independent site (n = 40), the AUC by the deep learning algorithm was 0.90. The present results support the possibility of using DCNN for automated diagnosis of RWMAs in the field of echocardiography.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Susceptibility-weighted MR sequence for the evaluation of ovarian masses with torsion., The British Journal of Radiology, Vol.93, No.1109, 20200110, 2020.
(Summary)
OBJECTIVES: Adnexal torsion is a rare gynecologic emergency caused by twisting of an adnexal mass. Twisted vascular pedicle is the most specific imaging finding for adnexal torsion, however, identification of twisted vascular pedicle can be challenging. The purpose of this study is to evaluate the feasibility of susceptibility-weighted magnetic resonance (MR) sequence (SWS) for the diagnosis of adnexal torsion. METHODS: MR imaging including SWS (SWAN: Susceptibility-weighted angiography) of surgically proven four benign ovarian masses with torsion (one acute and three subacute to chronic torsions) were retrospectively evaluated. Three cystic masses and one solid mass were included in this study. RESULTS: High signal intensity venous thrombus within the twisted vascular pedicle on T1-weighted imaging (T1WI) was detected in three lesions with subacute to chronic torsion (75%) but not in one lesion with acute torsion, whereas susceptibility-induced signal voids within the twisted vascular pedicle on SWAN were detected in all four lesions (100%). CONCLUSIONS: The demonstration of venous thrombus in the twisted vascular pedicle by SWS may be diagnostic for adnexal torsion. ADVANCES IN KNOWLEDGE: SWS can detect blood products sensitively and can reveal venous thrombus in the twisted vascular pedicle, which may be helpful for the diagnosis of adnexal torsion.
Kenya Kusunose, Akihiro Haga, Natsumi Yamaguchi, Takashi Abe, Daiju Fukuda, Hirotsugu Yamada, Masafumi Harada and Masataka Sata : Deep Learning for Assessment of Left Ventricular Ejection Fraction from Echocardiographic Images, Journal of the American Society of Echocardiography, Vol.33, No.5, 632-635, 2020.
Tatsuo Mori, Hiromichi Ito, Masafumi Harada, Sonoka Hisaoka, Yuki Matsumoto, Aya Goji, Yoshihiro Toda, Kenji Mori and Shoji Kagami : Multi-delay arterial spin labeling brain magnetic resonance imaging study for pediatric autism., Brain & Development, Vol.42, No.4, 315-321, 2020.
(Summary)
Arterial spin labeling (ASL) is a non-invasive magnetic resonance imaging (MRI) technique that can measure regional cerebral blood flow (rCBF) without radiation exposure. This study aimed to evaluate rCBF in individuals with autism and their age-matched controls, globally and regionally.
Nagahisa Murakami, Wataru Sako, Shotaroh Haji, T Furukawa, Y Otomi, H Otsuka, Yuishin Izumi, Masafumi Harada and Ryuji Kaji : Differences in Cerebellar Perfusion Between Parkinson's Disease and Multiple System Atrophy, Journal of the Neurological Sciences, Vol.409, 116627, 2020.
(Summary)
Objective biomarkers are required for differential diagnosis of Parkinson's disease (PD), multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). We aimed to determine if cerebellar blood flow, measured using N-isopropyl-[I] p-iodoamphetamine single photon emission computed tomography (I -IMP-SPECT), was useful for differentiating between PD, MSA and PSP. Twenty-four patients with PD, seventeen patients with MSA with predominant parkinsonian features (MSA-P), sixteenth patients with MSA with predominant cerebellar ataxia (MSA-C) and eight patients with PSP were enrolled. Twenty-seven normal controls' data were used for the calculation of z score. All patients underwent I -IMP-SPECT, and data were analyzed using a three-dimensional-stereotactic surface projection program. Cerebellar perfusion in MSA-P (MSA-P vs PD, P = .002; MSA-P vs PSP, P < .001) and MSA-C (MSA-C vs PD, P < .001; MSA-C vs PSP, P < .001) were significantly decreased compared with PD or PSP. There was no significant difference in perfusion between PD and PSP groups (P = .061). The area under the receiver operating characteristic curve for cerebellar perfusion between MSA-P and PD was 0.858. Our findings revealed that cerebellar perfusion by I-IMP-SPECT was useful for differentiating between PD and MSA-P.
Hozumi Yoshihara, Hidehiko Hosoki, Midori Yoshida, Yoshio Kume, Youichi Otomi, Masafumi Amano, Masao Yuasa, Kenji Yamada, Hideki Suito, Naoki Maeda, Naonobu Kawata, Masafumi Harada and Eiichi Honda : Changes in Image Examinations at the Department of Oral Radiology -The Number of Intraoral and Panoramic Radiographs-, Journal of Oral Health and Biosciences, Vol.32, No.1, 1-9, 2019.
(Summary)
After the computed radiography (CR) system was developed in 1986, it became possible to acquire, view and save digital images for medical diagnosis. Around that time, panoramic radiography was digitized by the CR system, but it was limited to large hospitals. From 1994, it has been digitized at large hospitals and dental clinics. We examined the changes in the number of intraoral and panoramic radiographs in dentistry, and based on the relationships among the numbers of radiographs, patients and dental operations, we discussed the clinical significance of digitization.<br>We extracted intraoral and panoramic radiography data, the number of dental operations and the number of patients from the database of Tokushima University Hospital from 2002 to 2017. Then, we extracted nationwide data from Statistics of Medical Care Activities in Public Health by the Ministry of Health, Labour and Welfare from 2002 to 2017.<br>As a result, although the numbers of patients and dental operations at Tokushima UniversityHospital have remained constant, the number of intraoral radiographs has decreased (72%), whereas the number of panoramic radiographs has increased annually since 2011 (131%). In addition, although the number of patients and nationwide insurance points increased in a different manner than that at Tokushima University Hospital, a decrease in the number of intraoral radiographs and an increase in the number of panoramic radiographs were noted across Japan. As panoramic imaging has been improved and adapted to different settings, panoramic radiography has been used instead of intraoral radiography, and it has been widely used in screening applications such as for perioperative patients. Although digitization is progressing, the analog images are still used (intraoral radiography analog rate, 29.7%, panoramic radiography analog rate, 12.4% in 2017).
Wataru Sako, Takashi Abe, Shotaroh Haji, Nagahisa Murakami, Yusuke Osaki, Yuishin Izumi, Masafumi Harada and Ryuji Kaji : A method for differential diagnosis of parkinsonian syndromes, Acta Neurologica Scandinavica, Vol.140, No.3, 229-235, 2019.
(Summary)
Neurological findings are important for the differential diagnosis of Parkinson's disease (PD), multiple system atrophy with predominant parkinsonian features (MSA-P), and progressive supranuclear palsy (PSP). There is currently no fast and reliable method to distinguish these patients. To address this, we propose a novel approach to measure midbrain and pons size using a longitudinal "one line" method from the mid-sagittal view. Structural images were acquired from 101 subjects who underwent 3.0 T MRI (20 controls, 44 PD, 20 MSA, 12 PSP, and 5 corticobasal syndrome). We measured the middle cerebellar peduncle (MCP), superior cerebellar peduncle (SCP), midbrain, and pons. Brainstem size was measured by area or length of the longitudinal axis, which we named the "one line" method. We conducted intraclass correlation coefficients to assess the extent of agreement and consistency among raters, and receiver operating characteristic curves were used to determine diagnostic accuracy. Intraclass correlation coefficients (ICC) of MCP width were excellent in sagittal and axial sections while those of SCP width were moderate. There were also excellent ICCs between raters for "one line" method of the midbrain and pons, while areas showed good ICCs. "One line" method and area of the midbrain were better than SCP width for the differential diagnosis of PSP from MSA-P and PD. In contrast, there was no clearly superior measurement for differentially diagnosing MSA-P. The "one line" method was comparable with area for inter-rater agreement and diagnostic accuracy even though this was a simple and fast way.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Reduced field-of-view diffusion-weighted MR imaging for assessing the local extent of uterine cervical cancer., Acta Radiologica, Vol.61, No.2, 267-275, 2019.
(Summary)
BACKGROUND: Recently, the evaluation of the tumor size and local extension of early-stage uterine cervical cancer on magnetic resonance imaging is important for the accurate clinical staging and to determine the indication of less extensive surgery such as fertility sparing radical trachelectomy. PURPOSE: To compare the diagnostic ability of reduced field-of-view diffusion-weighted imaging with those of three-dimensional (3D) contrast-enhanced T1-weighted imaging and T2-weighted imaging for assessing the tumor margin delineation and local extent of uterine cervical cancer. MATERIAL AND METHODS: 3T magnetic resonance images, including T2-weighted imaging, reduced field-of-view diffusion-weighted imaging, and 3D contrast-enhanced T1-weighted imaging, in 27 women with surgically proven cervical cancer (19 FIGO stage IB1, 3 IB2, and 5 IIA1) were retrospectively evaluated. Tumor margins and local tumor extent, including the presence of invasion to parametrium and vagina were evaluated on both sagittal and oblique axial (short axis) images; the results were compared with histologically confirmed tumor extension. RESULTS: Reduced field-of-view diffusion-weighted imaging diagnosed the tumor margins, which was more accurate than T2-weighted imaging ( P<0.001) and slightly better than 3D contrast-enhanced T1-weighted imaging. Reduced field-of-view diffusion-weighted imaging could define the tumor margins well even in small lesions (≤ 20 mm). Histological examination revealed parametrial invasion in two cases (clinically under-staged) and vaginal invasion in four cases. Reduced field-of-view diffusion-weighted imaging could demonstrate local extension of all lesions, which was more accurate than clinical examination and T2-weighted imaging. CONCLUSION: Addition of reduced field-of-view diffusion-weighted imaging may improve the staging accuracy of magnetic resonance imaging for cervical cancer in assessing the local tumor extent.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Clinical utility of susceptibility-weighted MR sequences for the evaluation of adnexal torsion, Proc. Intl. Soc. Mag. Reson. Med., Vol.27, 4040, 2019.
81.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : MR manifestations of polypoid endometriosis: Clinical feasibility of conventional and advanced MR techniques, Proc. Intl. Soc. Mag. Reson. Med., Vol.27, 4039, 2019.
82.
Yuki Kanazawa, Chiba Daiki, Masafumi Harada, Miyati Tosiaki, Miyoshi Mitsuharu, Hiroaki Hayashi, Yuki Matsumoto, Takashi Abe and Akihiro Haga : Thermal sensitive pH imaging using CEST, Proceedings of the 27th Annual Meeting of ISMRM, No.3991, 2019.
83.
Yuki Kanazawa, Masafumi Harada, Taniguchi Yo, Hiroaki Hayashi, Takashi Abe, Maki Ohtomo, Yuki Matsumoto, Ono Masafumi, Bito Yoshitaka and Akihiro Haga : Myelin imaging derived from quantitative parameter mapping, Proceedings of the 27th Annual Meeting of ISMRM, No.3313, 2019.
84.
Wataru Sako, Takashi Abe, Yuishin Izumi, Masafumi Harada and Ryuji Kaji : Deterministic-tractography-based approach for diagnosis and disease monitoring of amyotrophic lateral sclerosis, Clinical Neurology and Neurosurgery, Vol.181, 73-75, 2019.
(Summary)
Upper and lower motor neuron signs are required for the diagnosis of amyotrophic lateral sclerosis. The detection of upper motor neuron signs is key for the diagnosis, as quite a few patients with amyotrophic lateral sclerosis lack upper motor neuron signs during the course of disease. This study sought to investigate whether deterministic tractography of the corticospinal tract, reflecting upper motor neuron signs, could be a surrogate biomarker for amyotrophic lateral sclerosis. Fifteen patients with amyotrophic lateral sclerosis and ten controls underwent imaging on a 3.0 T MRI. The corticospinal tract was reconstructed using deterministic tractography, and the track number was calculated. We analyzed the differences between the groups and the relationship between the track number and disease severity, disease duration, progression rate or upper motor neuron signs. A reduction in the track number of the corticospinal tract was found in amyotrophic lateral sclerosis compared with controls (Student's t test, P = 0.008). The sensitivity and specificity were 0.67 and 0.9, respectively. The track number correlated with disease severity alone (r = 0.71, P = 0.003), and significantly associated with upper motor neuron signs (P = 0.004). These findings suggest that the deterministic-tractography-based approach is a potential biomarker for the diagnosis and disease monitoring of amyotrophic lateral sclerosis.
Nagahisa Murakami, Wataru Sako, Shotaroh Haji, Takahiro Furukawa, Yoichi Otomi, Hideki Otsuka, Yuishin Izumi, Masafumi Harada and Ryuji Kaji : Potential Utility of 123I-MIBG Scintigraphy as a Predictor of Falls in Parkinson's Disease, Frontiers in Neurology, Vol.10, 376, 2019.
(Summary)
Falls are associated with poor prognosis in patients with Parkinson's disease (PD). Although several factors related to falls were reported in patients with PD, objective predictors of falls are not identified. We aimed to determine whether I-meta-iodobenzylguanidine (MIBG) cardiac scintigraphy could be a useful biomarker to predict falls. Forty-five patients with PD were enrolled in this study. These subjects were followed up more than 5 years after MIBG scintigraphy and were divided into two groups: one with decreased uptake of MIBG and the other without decreased uptake of MIBG. The cut-off value for the delayed heart-to-mediastinum ratio was 1.8. Kaplan-Meier analysis and a log-rank test were performed to test the predictive power of MIBG cardiac scintigraphy for falls. Univariate analysis was selected because we did not have appropriate data for adjustment, such as motor and cognitive assessment. The group with decreased uptake of MIBG had a significantly higher incidence of falls than that without decreased uptake of MIBG ( = 0.022, log-rank test). Although the limitations of this study were lack of several key factors including motor and cognitive assessment, MIBG cardiac scintigraphy may be used to predict falls in patients with PD.
Yuki Kanazawa, Yuki Matsumoto, Masafumi Harada, Hiroaki Hayashi, Tsuyoshi Matsuda and Hideki Otsuka : Appropriate echo time selection for quantitative susceptibility mapping., Radiological Physics and Technology, Vol.12, 185-193, 2019.
(Summary)
The purpose of our study was to clarify the dependence of quantitative susceptibility mapping (QSM) on echo time (TE). We constructed a phantom consisting of six tubes; three tubes were filled with different concentrations (0.5, 1.0, and 2.5 mM) of gadopentetate dimeglumine (Gd-DTPA), and three were filled with different concentrations (100, 200, and 350 mg/mL) of calcium hydroxyapatite. Real and imaginary images from multi-echo spoiled gradient-echo data (12 echoes) were acquired. We then used four datasets with three serial echoes. The QSM procedure consists of four steps: field map estimation, phase unwrapping, background removal, and dipole inversion. For each sample, we compared the measured mean susceptibility value with the theoretical susceptibility value and conducted a linear regression analysis. Accordingly, the relationship between the measured susceptibility and concentration of Gd-DTPA was shown to agree well with the theoretical values (TEs = 16.4, 20.8, and 25.2 ms; slope = 0.24, R = 1.00). Furthermore, the relationship between the measured susceptibility and concentration of hydroxyapatite also showed good linearity (TEs = 16.4, 20.8, and 25.2 ms; slope = - 0.00121, R = 1.00). In conclusion, the optimization of the TE in QSM makes it possible to obtain more detailed information regarding the susceptibility of biomaterials.
Wataru Sako, Takashi Abe, T Furukawa, R Oki, Shotaroh Haji, Nagahisa Murakami, Yuishin Izumi, Masafumi Harada and Ryuji Kaji : Differences in the intra-cerebellar connections and graph theoretical measures between Parkinson's disease and multiple system atrophy, Journal of the Neurological Sciences, Vol.400, 129-134, 2019.
(Summary)
Parkinson's disease (PD) does not present with motor symptoms until dopaminergic neuronal loss exceeds 50%. This might indicate that a network-level compensatory mechanism involving surviving regions in PD acts to reduce brain abnormalities. In contrast, there is no evidence of a compensatory mechanism in multiple system atrophy (MSA). We hypothesized that a comparison of these two diseases would help to identify compensatory effects in PD. We recruited 23 patients with PD, 11 patients with MSA, and 11 controls that showed an aging brain but no neurological deficits. All subjects underwent resting state functional magnetic resonance imaging (fMRI). Regions of interest were defined according to the motor network related to the basal ganglia and cerebellum. Network-level analyses were performed. Network-based statistical analyses revealed that functional connectivity in PD brains was reduced between cerebellar lobules IX on both sides and vermis X, as compared with MSA brains. Transitivity was reduced in MSA as compared with controls. We demonstrated that a part of the intra-cerebellar connectivity was reduced in PD, and that network segregation was reduced in MSA. However, there was no evidence of compensatory effects in PD.
(Keyword)
Aged / Aged, 80 and over / Cerebellum / Female / Humans / Magnetic Resonance Imaging / Male / Middle Aged / Multiple System Atrophy / Nerve Net / Parkinson Disease
Chisato Tonoiso, Hitoshi Ikushima, Akiko Kubo, Takashi Kawanaka, Shunsuke Furutani, Takaharu Kudoh, Takahiro Yoshida, Hiroshi Miyamoto, Masafumi Harada, Tetsuji Takayama and Akira Tangoku : Clinical outcomes and prognostic factors of definitive radiotherapy for esophageal cancer, The Journal of Medical Investigation : JMI, Vol.66, No.1, 2, 99-105, 2019.
(Summary)
Purpose To assess the treatment results of definitive radiotherapy for esophageal cancer at Tokushima University Hospital and clarify the prognostic factors. Methods Seventy consecutive patients with esophageal cancer who underwent definitive radiotherapy between May 2004 and March 2012 were included in the present study. Local control rate, overall survival rate, and radiation morbidity were examined and univariate and multivariate analyses were performed to investigate prognostic factors. Results The 5-yearoverall survival rates of stages I, II, III, and IVA were 81%, 71%, 0%, and 9%, respectively. Performance status, clinical stage, and neoadjuvant chemotherapy were significant prognostic factors. A past history of interstitial pneumonia was associated with severe radiation-induced lung injury. Conclusions Patients who underwent definitive chemoradiotherapy for esophageal cancer in stage I/II showed good prognosis. However, treatment results of the patients in stage III/IV were not satisfactory, and those who could not undergo surgery after neoadjuvant chemotherapy had the worst prognosis.J.Med.Invest.66:99-105, February, 2019.
(Keyword)
esophageal cancer / radiotherapy / chemoradiotherapy
Shunsuke Furutani, Hitoshi Ikushima, Motoharu Sasaki, Chisato Tonoiso, Ayaka Takahashi, Akiko Kubo, Takashi Kawanaka and Masafumi Harada : Clinical outcomes of hypofractionated image-guided multifocal irradiation using volumetric-modulated arc therapy for brain metastases., Journal of Radiation Research, Vol.60, No.1, 134-141, 2019.
(Summary)
Volumetric-modulated arc therapy (VMAT) can be used to design hypofractionated radiotherapy treatment plans for multiple brain metastases. The purpose of this study was to evaluate treatment outcomes of hypofractionated image-guided multifocal irradiation using VMAT (HFIGMI-VMAT) for brain metastases. From July 2012 to December 2016, 67 consecutive patients with 601 brain metastases were treated with HFIGMI-VMAT at our institution. The prescribed dose was 50 Gy to a 95% volume of the planning target volume in 10 fractions. Fifty-five of the 67 patients had non-small-cell lung cancer, and the remaining 12 had other types of cancer. The median number of brain metastases was five, and the median maximum diameter was 1.2 cm. The median duration of follow-up was 12.0 months (range, 1.9-44.8 months), and the median survival time 18.7 months. Four patients with six lesions had local recurrences. The local control rate in the 64 assessed patients was 98.4% and 95.3% at 6 and 12 months, respectively (three died before assessment). The local control rate for the 572 assessed lesions was 99.8% and 99.3% at 6 and 12 months, respectively. Thirty-nine patients developed distant brain metastases, the distant brain control rate being 59.7% and 40.5% at 6 and 12 months, respectively. Acute toxicities were generally mild (Grade 1-2). Three patients (4.5%) developed radiation necrosis requiring corticosteroid therapy. The HFIGMI-VMAT technique with flat dose delivery was well tolerated and achieved excellent local control. This technique is a promising treatment option for patients with multiple and large brain metastases.
Youichi Otomi, Hideki Otsuka, Kaori Terazawa, Moriaki Yamanaka, Yuki Obama, Maki Arase, Maki Otomo, Saho Irahara, Michiko Kubo, Naoto Uyama, Takashi Abe and Masafumi Harada : The diagnostic ability of SPECT/CT fusion imaging for gastrointestinal bleeding: a retrospective study., BMC Gastroenterology, Vol.18, No.1, 183, 2018.
(Summary)
Blood loss from the gastrointestinal tract can be an acute and life-threatening event. For the treatment of gastrointestinal bleeding, it is important to accurately detect gastrointestinal bleeding and to localize the sites of bleeding. The purpose of this study was to retrospectively assess the capabilities of SPECT/CT in the diagnosis of gastrointestinal bleeding by a comparison with planar imaging alone as well as planar and SPECT. We conducted a retrospective analysis of 20 patients (21 examinations) who underwent gastrointestinal bleeding scintigraphy in the past 7ears and in whom the bleeding site was identified by endoscopy or capsule endoscopy, or in whom no evidence of gastrointestinal bleeding was identified during the clinical course. Five patients (5 examinations) were diagnosed by planar imaging (planar group). Eight patients (9 examinations) were diagnosed by planar imaging and SPECT (planar + SPECT group). Seven patients (7 examinations) were diagnosed by planar imaging and SPECT/CT (planar + SPECT/CT group). We calculated the diagnostic ability of each method in detecting the presence of bleeding, as well as the ability of each method to identify the sites of bleeding. The sensitivity, specificity, and accuracy of the methods were compared. The diagnostic ability of the three imaging methods in detecting the presence of gastrointestinal bleeding was as follows. Planar imaging showed 100% sensitivity (3/3), 100% specificity (2/2), and 100% accuracy (5/5). Planar + SPECT imaging showed 85.7% sensitivity (6/7), 100% specificity (2/2), and 88.9% accuracy (8/9). Planar + SPECT/CT imaging showed 100% sensitivity (6/6), 100% specificity (1/1), and 100% accuracy (7/7). The diagnostic ability of the three modalities in detecting the site of bleeding was as follows: planar, 33.3% (1/3); planar + SPECT, 71.4% (5/7); and planar + SPECT/CT, 100% (6/6). All 3 imaging methods showed good accuracy in detecting the presence of gastrointestinal bleeding. The addition of SPECT or SPECT/CT made the anatomical position of the uptake clear and contributed to the localization of the site of gastrointestinal bleeding. Planar + SPECT/CT imaging therefore showed the highest diagnostic ability for detecting the site of gastrointestinal bleeding.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Clinical utility of susceptibility-weighted MR sequence for the evaluation of uterine sarcomas., Clinical Imaging, Vol.53, 143-150, 2018.
(Summary)
PURPOSE: High intensity intra-tumoral hemorrhagic necrosis on T1-weighted images is a suggestive finding for uterine sarcomas, however, the reported prevalence varies. The purpose of this study is to evaluate the capability of susceptibility-weighted MR sequences (SWS) for the diagnosis of uterine sarcomas. MATERIALS AND METHODS: MR imaging of surgically proven 10 uterine sarcomas and 24 benign leiomyomas were retrospectively evaluated for the presence of high intensity areas on T1-weighted images and signal voids on SWS (T2 star-weighted angiography: SWAN). RESULTS: High intensity areas on T1-weighted images and signal voids on SWS were observed in 40% and 100% of sarcomas, whereas 0% and 4% of leiomyomas, respectively. The accuracy, sensitivity, and specificity for T1-weighted images were 82%, 40%, and 100%, and for SWS were 97%, 100%, and 96%, respectively. CONCLUSION: The demonstration of intra-tumoral hemorrhage in patients suspected with uterine sarcomas by SWS may provide valuable diagnostic findings.
Mayumi Takeuchi, Kenji Matsuzaki, Yoshimi Bando and Masafumi Harada : Evaluation of Red Degeneration of Uterine Leiomyoma with Susceptibility-weighted MR Imaging, Magnetic Resonance in Medical Sciences, Vol.18, No.2, 158-162, 2018.
Shinji Nagahiro, Yoshiteru Tada, Junichiro Satomi, Tomoya Kinouchi, Kazuyuki Kuwayama, Kenji Yagi, Kohhei Nakajima, Nobuhisa Matsushita, Takeshi Miyamoto, Tadashi Yamaguchi, Kenji Shimada, Masaaki Korai, Hideo Mure, Y Okayama, Takashi Abe, Masafumi Harada, Keiko T. Kitazato and Yasuhisa Kanematsu : Treatment of Unruptured Cerebral Aneurysms with the Mineralocorticoid Receptor Blocker Eplerenone-Pilot Study., Journal of Stroke & Cerebrovascular Diseases, Vol.27, No.8, 2134-2140, 2018.
(Summary)
Currently there are no pharmacological therapies for patients with unruptured cerebral aneurysms. Elsewhere we showed that the mineralocorticoid receptor antagonist eplerenone prevented the formation of cerebral aneurysms in our ovariectomized hypertensive aneurysm rat model. The current pilot study evaluated whether it can be used to prevent the growth and rupture of cerebral aneurysms in hypertensive patients. Between August 2011 and May 2014, we enrolled 82 patients with 90 aneurysms in an open-label uncontrolled clinical trial. All provided prior informed consent for inclusion in this study, and all were treated with eplerenone (25-100 mg/d). The primary end points of our study were the rupture and enlargement of the cerebral aneurysms. Of the 82 patients, 80 (88 unruptured aneurysms) were followed for a mean of 21.3 months (153.4 aneurysm-years); 12 patients (15.0%) permanently discontinued taking the drug. One month after the start of eplerenone administration and throughout the follow-up period, eplerenone kept the blood pressure within the normal range. Most notably, no aneurysms smaller than 9 mm ruptured or enlarged. However, of 2 large thrombosed aneurysms, 1 enlarged and the other ruptured. The overall annual rupture rate was .65%; it was 13.16% for aneurysms larger than 10 mm; the overall annual rate for reaching the primary end points was 1.30%. Our observations suggest that eplerenone may help to prevent the growth and rupture of unruptured cerebral aneurysms smaller than 9 mm. To assess its potential long-term clinical benefits, large clinical trials are needed.
Shunya Nakane, Koji Fujita, Shingo Azuma, Ryo Urushihara, Masaki Kamada, Masafumi Harada, Yuishin Izumi and Ryuji Kaji : CSF cystatin C and diffusion tensor imaging parameters as biomarkers of upper motor neuron degeneration in amyotrophic lateral sclerosis., Clinical Neurology and Neurosurgery, Vol.172, 162-168, 2018.
(Summary)
Reduced cystatin C in CSF can reflect UMN involvement as shown in high-field MR of ALS, potentially providing a new biomarker for UMN degeneration in ALS.
(Keyword)
Adult / Aged / Aged, 80 and over / Amyotrophic Lateral Sclerosis / Biomarkers / Cystatin C / Diffusion Magnetic Resonance Imaging / Diffusion Tensor Imaging / Female / Humans / Magnetic Resonance Spectroscopy / Male / Middle Aged / Motor Neurons / Multimodal Imaging / Nerve Degeneration
Masashi Ohta, Masahito Nakataki, Tomoya Takeda, Shusuke Numata, Takeo Tominaga, Naomi Kameoka, Hiroko Kubo, Makoto Kinoshita, K Matsuura, M Otomo, N Takeichi, Masafumi Harada and Tetsuro Ohmori : Structural equation modeling approach between salience network dysfunction, depressed mood, and subjective quality of life in schizophrenia: an ICA resting-state fMRI study., Neuropsychiatric Disease and Treatment, Vol.14, 1585-1597, 2018.
(Summary)
Quality of life (QOL) is an important clinical outcome for patients with schizophrenia, and recent studies have focused on subjective QOL. We evaluated the causal relationship between psychosocial aspect of subjective QOL, symptoms, cognitive functions, and salience network (SN) dysfunction in schizophrenia using structural equation modeling (SEM). We performed a cross-sectional study of 21 patients with symptomatically stabilized schizophrenia and 21 age-, sex-, and education level-matched healthy controls who underwent resting-state functional magnetic resonance imaging. We evaluated SN dysfunction in schizophrenia using independent component analysis (ICA). We rated participant psychopathology using the Positive and Negative Syndrome Scale (PANSS), the Brief Assessment of Cognition in Schizophrenia (BACS), and the Calgary Depression Scale for Schizophrenia (CDSS). We rated psychosocial aspect of subjective QOL using the Schizophrenia Quality of Life Scale (SQLS) psychosocial subscale. We applied SEM to examine the relationships between SN dysfunction, PANSS positive and negative scores, CDSS total scores, BACS composite scores, and SQLS psychosocial subscale scores. In second-level analysis after group ICA, patient group had significant lower right pallidum functional connectivity (FC) within the SN than the controls did (Montreal Neurological Institute [MNI] [] = [22 -2 -6]) ( = 0.027, family-wise error [FWE] corrected). In SEM, we obtained a good fit for an SEM model in which SN dysfunction causes depressed mood, which in turn determines psychosocial aspect of subjective QOL (chi-squared = 0.9, root mean square error of approximation (RMSEA) < 0.001, comparative fit index [CFI] = 1.00, and standardized root mean square residual [SRMR]= 0.020). We found a continuous process by which SN dysfunction causes depressed moods that determine psychosocial aspect of subjective QOL in schizophrenia. This is the first report that offers a unified explanation of functional neuroimaging, symptoms, and outcomes. Future studies combining neuroimaging techniques and clinical assessments would elucidate schizophrenia's pathogenesis.
Yuki Kanazawa, Kotaro Baba, Tosiaki Miyati, Masafumi Harada, Hiroaki Hayashi, Ikuho Kosaka, Mitsuharu Miyoshi, Michael Carl and Yuki Matsumoto : Does the amount of signal change depend on calcium concentration in lipid-rich core plaque?, Proceedings of the 26th Annual Meeting of ISMRM, No.3473, 2018.
99.
Yuki Kanazawa, Toshiaki Sasaki, Hiroaki Hayashi, Kotaro Baba, Ikuho Kosaka, Yuki Matsumoto, Mitsuharu Miyoshi and Masafumi Harada : T1 dependency of magnetization transfer effect in human brain, Proceedings of the 26th Annual Meeting of ISMRM, No.3179, 2018.
100.
Yuki Kanazawa, Masafumi Harada, Mitsuharu Miyoshi, Ikuho Kosaka, Kotaro Baba, Hiroaki Hayashi and Yuki Matsumoto : Nuclear Overhauser enhancement effect of low B1 power CEST RF in human brain at 3.0 T, Proceedings of the 26th Annual Meeting of ISMRM, No.5117, 2018.
101.
Kageyuki Oba, Minetaka Maeda, Gulinu Maimaituxun, Satoshi Yamaguchi, Osamu Arasaki, Daiju Fukuda, Shusuke Yagi, Hirata Yukina, Susumu Nishio, Takashi Iwase, Shoichiro Takao, Kenya Kusunose, Hirotsugu Yamada, Takeshi Soeki, Tetsuzo Wakatsuki, Masafumi Harada, Hiroaki Masuzaki, Masataka Sata and Michio Shimabukuro : Effect of the Epicardial Adipose Tissue Volume on the Prevalence of Paroxysmal and Persistent Atrial Fibrillation., Circulation Journal, Vol.82, No.7, 1778-1787, 2018.
(Summary)
Although increasing evidence suggests that epicardial adipose tissue volume (EATV) is associated with atrial fibrillation (AF), it is controversial whether there is a dose-response relationship of increasing EATV along the continuum of AF. We evaluated the effect of the EATV on the prevalence of paroxysmal AF (PAF) and persistent AF (PeAF) and the relationships with cardiac structure and functional remodeling.Methods and Results:Subjects who underwent multidetector computed tomography (MDCT) coronary angiography because of symptoms suggestive of coronary artery disease were divided into sinus rhythm (SR) (n=112), PAF (n=133), and PeAF (n=71) groups. The EATV index (EATV/body surface area, mL/m) was strongly associated with the prevalence of PAF and PeAF on the model adjusted for known AF risk factors. The effect of the EATV index on the prevalence of PeAF, but not on that of PAF, was modified by the left atrial (LA) dimension, suggesting that extension of the LA dimension is related to EATV expansion in PeAF. The cutoff value of the EATV index for the prevalence was higher in PeAF than in PAF (64 vs. 55 mL/m, P<0.01). The EATV index is associated with the prevalence of PAF and PeAF, and its cutoff values are predictive for PAF and PeAF development independently of other AF risk factors.
Mayumi Takeuchi, Kenji Matsuzaki, Yoshimi Bando, Masato Nishimura, Aki Hayashi and Masafumi Harada : A Case of Uterine Tumor Resembling Ovarian Sex-cord Tumor (UTROSCT) Exhibiting Similar Imaging Characteristics to Those of Ovarian Sex-cord Tumor., Magnetic Resonance in Medical Sciences, Vol.18, No.2, 113-114, 2018.
Natsuki Ikemitsu, Yuki Kanazawa, Yuki Matsumoto, Hiroaki Hayashi, Toshiaki Sasaki, Mitsuharu Miyoshi and Masafumi Harada : Development of correction for signal-to-noise ratio using a T2* with improved Phase method, Journal of Computer Assisted Tomography, Vol.42, No.1, 117-123, 2018.
(Summary)
This study aims to improve the signal-to-noise ratio (SNR) of the phase image focusing T2 and to develop an improved phase (iPhase) image acquired high SNR. The iPhase images of phantom and brain were acquired with multi-echo spoiled gradient-echo. The phantom component was a gadopentetate dimeglumine (Gd-DTPA) solution made of different concentrations (0.1, 0.5, and 1 wt%) and Gd-DTPA (0.1, 0.5, and 1 wt%) with agar (1.0 wt%). We applied the iPhase image to susceptibility weighed image (SWI) and evaluated SNR of SWI. In phantom study, SNRs of conventional SWI at each sample were 19.8, 15.7, 7.4, 20.0, 17.4, and 27.3, respectively. Signal-to-noise ratios of SWI derived from iPhase method were 29.5, 33.7, 21.7, 28.5, 24.3, and 14.7, respectively. Then, the SNR showed an improvement of 196% at maximum (for the Gd-DTPA 1 wt% sample). In healthy volunteer study, SWI derived from iPhase method had the good contrast between white matter and gray matter. The iPhase image was able to improve the phase SNR. Moreover, iPhase method makes it possible to obtain a high SNR image when applying to SWI.
Michihiro Nakamura, Koichiro Hayashi, Hitoshi Kubo, Masafumi Harada, Keisuke Izumi, Yoshihiro Tsuruo and Toshinobu Yogo : Mesoscopic multimodal imaging provides new insight to tumor tissue evaluation: an example of macrophage imaging of hepatic tumor using organosilica nanoparticles., Scientific Reports, Vol.7, No.1, 3953, 2017.
(Summary)
Multimodal imaging using novel multifunctional nanoparticles provides new approach to biomedical field. Thiol-organosilica nanoparticles containing iron oxide magnetic nanoparticles (MNPs) and rhodamine B (thiol OS-MNP/Rho) were applied to multimodal imaging of hepatic tumor of Long-Evans Cinnamon (LEC) rat. The magnetic resonance imaging (MRI) of LEC rats revealed tumors in the liver clearly and semi-quantitatively due to a labeling of macrophages in liver. The fluorescent imaging (FI) showed abnormal fluorescent patterns of the liver at the mesoscopic level that was between macroscopic and microscopic level. We performed correlation analysis between optical imaging including FI and MRI. We found that the labeled macrophages located specific area in the tumor tissue and influenced the tumor size on MRI. In addition histological observation showed the labeled macrophages related specific tissue in the pathological region. We demonstrated a new approach to evaluate tumor tissue at the macroscopic and microscopic level as well as mesoscopic level using multimodal imaging.
Naoto Uyama, Hideki Otsuka, Takayoshi Shinya, Youichi Otomi, Masafumi Harada, Wataru Sako, Yuishin Izumi, Ryuji Kaji, Yuya Watanabe, Satoru Takashi and Yamato Kunikane : The utility of the combination of a SPECT study with [123I]-FP-CIT of dopamine transporters and [123I]-MIBG myocardial scintigraphy in differentiating Parkinson disease from other degenerative parkinsonian syndromes., Nuclear Medicine Communications, Vol.38, No.6, 487-492, 2017.
(Summary)
Molecular imaging of nigrostriatal dopamine transporters (DAT) and sympathetic cardiac innervation with single-photon emission computed tomography (SPECT) are useful tools for differentiating idiopathic Parkinson disease (PD) from other degenerative parkinsonian syndromes (non-PD). Nevertheless, these modalities are often insufficient for achieving a definite diagnosis. The aims of this study were to evaluate the diagnostic accuracy of the combination of these tools. The SPECT radiotracers [I]-N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)-nortropane (FP-CIT) and meta-[I]-iodobenzylguanidine (MIBG) were used to research presynaptic dopaminergic projections (DAT SPECT) and myocardial adrenergic innervation (MIBG scintigraphy), respectively. PD patients (n=15; age: 61.5±13.6 years) and non-PD patients (n=19; age: 62.6±14.2 years) who underwent both tests were enrolled in this study. Receiver-operating characteristic analyses were used to set the cutoff values of the specific binding ratio in DAT SPECT and the heart to mediastinum ratio in delayed scan in MIBG scintigraphy for differentiating PD from non-PD. We calculated the sensitivity, specificity, and test accuracy of the individual methods and also the combination of these two modalities. When DAT SPECT and MIBG scintigraphy were used individually, they showed mild accuracy in differentiating PD from non-PD (DAT, 67.6%; MIBG, 67.6%). The combination of the two approaches using cutoff values of less than 3.24 for the specific binding ratio and less than 2.745 for the delayed heart to mediastinum ratio enabled more accurate differentiation between PD and non-PD. The accuracy of these indices in distinguishing PD from non-PD was 79.4%. These results suggested that the combination of DAT SPECT and MIBG scintigraphy may improve the diagnostic accuracy in differentiating PD from non-PD.
Mayumi Takeuchi, Kenji Matsuzaki, Koichi Tsuneyama, Masato Nishimura, Eri Takiguchi and Masafumi Harada : Ovarian Large Cell Neuroendocrine Carcinoma Associated with Serous Carcinoma: Correlation of Pathology with MR Imaging, Magnetic Resonance in Medical Sciences, Vol.16, No.4, 273-274, 2017.
Ichiro Tonogai, Tetsuya Matsuura, Toshiyuki Iwame, Keizo Wada, Tomoya Takasago, Tomohiro Goto, Daisuke Hamada, Yohei Kawatani, Eiki Fujimoto, Tetsuya Kitagawa, Shoichiro Takao, Seiji Iwamoto, Moriaki Yamanaka, Masafumi Harada and Koichi Sairyo : Pseudoaneurysm of the Anterior Tibial Artery following Ankle Arthroscopy in a Soccer Player., Case Reports in Orthopedics, 2017.
(Summary)
Ankle arthroscopy carries a lower risk of vascular complications when standard anterolateral and anteromedial portals are used. However, the thickness of the fat pad at the anterior ankle affords little protection for the thin-walled anterior tibial artery, rendering it susceptible to indirect damage during procedures performed on the anterior ankle joint. To our knowledge, only 11 cases of pseudoaneurysm involving the anterior tibial artery after ankle arthroscopy have been described in the literature. Here we reported a rare case of a 19-year-old soccer player who presented with pseudoaneurysm of the anterior tibial artery following ankle arthroscopy using an ankle distraction method and underwent anastomosis for the anterior tibial artery injury. Excessive distraction of the ankle puts the neurovascular structures at greater risk for iatrogenic injury of the anterior tibial artery during ankle arthroscopy. Surgeons should look carefully for postoperative ankle swelling and pain after ankle arthroscopy.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Evaluating Myometrial Invasion in Endometrial Cancer: Comparison of Reduced Field-of-view Diffusion-weighted Imaging and Dynamic Contrast-enhanced MR Imaging, Magnetic Resonance in Medical Sciences, Vol.17, No.1, 28-34, 2017.
(Summary)
To compare the diagnostic ability of reduced field-of-view (FOV) diffusion-weighted (DW) magnetic resonance (MR) imaging with that of three-dimensional (3D) dynamic contrast-enhanced (DCE) MR imaging in evaluating the depth of myometrial invasion in patients with endometrial cancer. Three tesla (3T) MR images including T2-weighted imaging, reduced FOV DW imaging and 3D DCE MR imaging in sagittal and oblique axial (short axis) planes in 25 women with surgically proven endometrial cancer were retrospectively evaluated. The depth of myometrial invasion (stage S: < 50% vs stage D: ≥ 50%) on MR imaging was correlated with surgical pathology results. The 25 endometrial cancers included 16 stage S and 9 stage D tumors. The depth of myometrial invasion could be accurately evaluated in 68% of the cases for T2-weighted imaging, 92% for 3D DCE MR imaging, and 96% for reduced FOV DW imaging. In two patients with coexisting adenomyosis, both T2-weighted imaging and 3D DCE MR imaging failed to reveal the deep myometrial invasion, and reduced FOV DW imaging clearly demonstrated the tumor margin in the cases. Combination of reduced FOV DW imaging reading together with T2-weighted imaging improved the assessment of myometrial invasion with a diagnostic accuracy of up to 100%. Addition of reduced FOV DW imaging may improve the staging accuracy of MR imaging for endometrial cancer in assessing the depth of myometrial invasion. Especially, reduced FOV DW imaging has an advantage in assessing the depth of myometrial invasion for patients with coexisting adenomyosis. Reduced FOV DW imaging can be an alternative to 3D DCE MR imaging in evaluating myometrial invasion of endometrial cancer without the use of contrast medium.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Red degeneration of uterine leiomyoma: Clinical utility of susceptibility-weighted MR imaging, Proc. Intl. Soc. Mag. Reson. Med., Vol.25, 4814, 2017.
112.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Myometrial invasion in endometrial cancer: Comparison of reduced field-of-view diffusion-weighted imaging and dynamic contrast-enhanced magnetic resonance imaging, Proc. Intl. Soc. Mag. Reson. Med., Vol.25, 4813, 2017.
113.
Hiromichi Ito, Kenji Mori, Masafumi Harada, Sonoka Hisaoka, Yoshihiro Touda, Tatsuo Mori, Aya Gohji, Yoko Abe, Masahito Miyazaki and Shoji Kagami : A Proton Magnetic Resonance Spectroscopic Study in Autism Spectrum Disorder Using a 3-Tesla Clinical Magnetic Resonance Imaging (MRI) System: The Anterior Cingulate Cortex and the Left Cerebellum., Journal of Child Neurology, Vol.32, No.8, 731-739, 2017.
(Summary)
The pathophysiology of autism spectrum disorder (ASD) is not fully understood. We used proton magnetic resonance spectroscopy to investigate metabolite concentration ratios in the anterior cingulate cortex and left cerebellum in ASD. In the ACC and left cerebellum studies, the ASD group and intelligence quotient- and age-matched control group consisted of 112 and 114 subjects and 65 and 45 subjects, respectively. In the ASD group, γ-aminobutyric acid (GABA)+/ creatine/phosphocreatine (Cr) was significantly decreased in the anterior cingulate cortex, and glutamate (Glu)/Cr was significantly increased and GABA+/Cr was significantly decreased in the left cerebellum compared to those in the control group. In addition, both groups showed negative correlations between Glu/Cr and GABA+/Cr in the left cerebellum, and positive correlations between GABA+/Cr in the anterior cingulate cortex and left cerebellum. ASD subjects have hypoGABAergic alterations in the anterior cingulate cortex and hyperglutamatergic/hypoGABAergic alterations in the left cerebellum.
Shu Sogabe, Junichiro Satomi, Yoshiteru Tada, Yasuhisa Kanematsu, Kazuyuki Kuwayama, Kenji Yagi, Shotaroh Yoshioka, Yoshifumi Mizobuchi, Hideo Mure, Izumi Yamaguchi, Takashi Abe, Nobuaki Yamamoto, Keiko Kitazato, Ryuji Kaji, Masafumi Harada and Shinji Nagahiro : Intra-arterial high signals on arterial spin labeling perfusion images predict the occluded internal carotid artery segment, Neuroradiology, Vol.59, No.6, 587-595, 2017.
(Summary)
Arterial spin labeling (ASL) involves perfusion imaging using the inverted magnetization of arterial water. If the arterial arrival times are longer than the post-labeling delay, labeled spins are visible on ASL images as bright, high intra-arterial signals (IASs); such signals were found within occluded vessels of patients with acute ischemic stroke. The identification of the occluded segment in the internal carotid artery (ICA) is crucial for endovascular treatment. We tested our hypothesis that high IASs on ASL images can predict the occluded segment. Our study included 13 patients with acute ICA occlusion who had undergone angiographic and ASL studies within 48 h of onset. We retrospectively identified the high IAS on ASL images and angiograms and recorded the occluded segment and the number of high IAS-positive slices on ASL images. The ICA segments were classified as cervical (C1), petrous (C2), cavernous (C3), and supraclinoid (C4). Of seven patients with intracranial ICA occlusion, five demonstrated high IASs at C1-C2, suggesting that high IASs could identify stagnant flow proximal to the occluded segment. Among six patients with extracranial ICA occlusion, five presented with high IASs at C3-C4, suggesting that signals could identify the collateral flow via the ophthalmic artery. None had high IASs at C1-C2. The mean number of high IAS-positive slices was significantly higher in patients with intra- than extracranial ICA occlusion. High IASs on ASL images can identify slow stagnant and collateral flow through the ophthalmic artery in patients with acute ICA occlusion and help to predict the occlusion site.
Mitsuharu Miyoshi, Masafumi Harada, Yuki Kanazawa and Hiroyuki Kabasawa : CEST and Binding Water MT Separation in Brain Tumor by Multi Pool Model CEST Peak Extraction Method, Proceedings of the 25th Annual Meeting of ISMRM, 4242, 2017.
116.
Yuki Kanazawa, Masafumi Harada, Mitsuharu Miyoshi, Yuki Matsumoto, Hiroaki Hayashi, Toshiaki Sasaki and Natsuki Ikemitsu : Baseline of Chemical Exchange Saturation Transfer Imaging for Brain, Proceedings of the 25th Annual Meeting of ISMRM, 4646, 2017.
117.
Yuki Kanazawa, Masafumi Harada, Mitsuharu Miyoshi, Yuki Matsumoto, Hiroaki Hayashi, Toshiaki Sasaki, Natsuki Ikemitsu and Michael Carl : Dura Mater imaging with UTE T2* Mapping, Proceedings of the 25th Annual Meeting of ISMRM, 4682, 2017.
118.
Hiroaki Hayashi, Yoshiki Mihara, Natsumi Kimoto, Takashi Asahara, Kenji Yamada, Yuki Kanazawa, Masafumi Harada, Tohru Okazaki and Takuya Hashizume : Preliminary study for exposure dose measurement of people assisting during a pediatric X-ray procedure by means of a small-type OSL dosimeter, European Congress of Radiology, C-0034-1-C-0034-19, 2017.
(Summary)
[Aims and objectives] During a pediatric X-ray procedure, medical staff or other people such as parents may assist to hold children during the X-ray examination. In this situation, these assistances are exposed by scattered X-rays, but there are no precise data concerning exposure doses. The aim of this study is to measure exposure dose of people assisting during the X-ray procedure. [Methods and materials] We used small-type OSL dosimeter (Landauer), which was sufficiently initialized. The detection limit of our system was estimated to be 0.5 micro-Gy. The OSL dosimeter was attached outside the lead protector which was worn by the assistant. In order to reduce contamination from background X- and/or gamma-rays, the exposed dosimeters were analyzed within 12 hours. The X-ray diagnostic system consisted of X-ray equipment and flat-panel detector which has auto-exposure control. The typical irradiation condition was SID=1.1 m, 3.2 mAs, and 53 kV. [Results] The exposure doses of assistances in the position outside the lead protector were approximately 3 micro-Gy. We measured 5 cases, in which patient's ages were 7 months to 1 year 6 months. Patient age showed no significant differences in exposure doses. [Conclusion] For the first time, using the small-type OSL dosimeter, we measured exposure dose of people assisting during a pediatric X-ray examination in a position outside the lead protector. The measured value was extremely low. Our actual data supports the justification of the situation in which someone should hold a child during an X-ray procedure.
Natsuki Ikemitsu, Yuki Kanazawa, Yuki Matsumoto, Hiroaki Hayashi, Takatoshi Usuda, Toshiaki Sasaki, Mitsuharu Miyoshi and Masafumi Harada : An improvement of signal-to-noise ratio for phase image, European Congress of Radiology (EPOS), C-0803, 2017.
Toshiaki Sasaki, Yuki Kanazawa, Yuki Matsumoto, Hiroaki Hayashi, Natsuki Ikemitsu, Takatoshi Usuda, Mitsuharu Miyoshi and Masafumi Harada : T1 dependence of magnetization transfer effect for macromolecules, European Congress of Radiology (EPOS), C-0827, 2017.
(Summary)
Purpose: To assess the relationship between T1 and magnetization transfer (MT) effect on macromolecules, we determined T1 map derived from variable flip angle (VFA) method with MT pulse. Materials and Methods: On a 3.0 T magnetic resonance (MR) system, we performed a phantom study using spoiled gradient-echo sequences; TR, 600 ms; TE, 5.8 ms; FA, 5, 20, 40, 60, and 90 degrees; without and with MT pulse (offset frequency, 800 ,1200 , and 1600 Hz). The phantom components were six samples; water and polyethylene glycol (PEG) solutions at different concentrations (10, 20, 30, 40, and 50 wt%). We calculated T1 maps from image datasets without and with MT pulse. Then, the MT ratio (MTR) maps were calculated from each FA image. Results: The mean T1 range without MT pulse for each sample was from 1200 to 2039 ms. The mean T1 ranges with MT pulse of each sample were from 1322 to 1886 at 800 Hz; from 1310 to 1926 ms at 1200 Hz; from 1300 to 1909 ms at 1600 Hz. The MTR of each sample showed the highest value at FA 5 degrees and offset 800 Hz. The mean MTR values of each sample were 6.54 ± 2.78, 3.94 ± 1.92, 2.50 ± 1.67, 1.96 ± 1.33, 1.44 ± 1.15, and 1.78 ± 1.53%. Conclusion: Determination of T1 with MT pulse makes it possible to obtain more detailed information of macromolecules.
Wataru Sako, Takashi Abe, Yuishin Izumi, Hiroki Yamazaki, Naoko Matsui, Masafumi Harada and Ryuji Kaji : Spontaneous brain activity in the sensorimotor cortex in amyotrophic lateral sclerosis can be negatively regulated by corticospinal fiber integrity., Neurological Sciences, Vol.38, No.5, 755-760, 2017.
(Summary)
Previous studies failed to detect reduced value of the amplitude of low frequency fluctuation (ALFF) derived from resting state functional magnetic resonance imaging in the primary motor cortex in amyotrophic lateral sclerosis (ALS) though primary motor cortex was mainly affected with ALS. We aimed to investigate the cause of masking the abnormality in the primary motor cortex in ALS and usefulness of ALFF for differential diagnosis among diseases showing muscle weakness. We enrolled ten patients with ALS and eleven disease controls showing muscle weakness. Voxel-wise analysis revealed that significant reduction of ALFF value was present in the right sensorimotor cortex in ALS. There was a significant negative correlation between ALFF value in the right sensorimotor cortex and fractional anisotropy (FA) value in the posterior limbs of the internal capsule (PLIC). For a diagnostic tool, the area under receiver operating characteristic curve improved if the ALS patients with disease duration >1 year were excluded. The present findings raised the possibility of usefulness of ALFF value in the sensorimotor cortex for differential diagnosis of ALS, and supported the notion that adjustment for FA value in the PLIC could improve accuracy.
Mitsuhiro Kinoshita, Ryozo Shirono, Katsuya Takechi, Hironobu Yonekura, Seiji Iwamoto, Takayoshi Shinya, Shoichiro Takao and Masafumi Harada : The Usefulness of Virtual Fluoroscopic Preprocedural Planning During Percutaneous Transhepatic Biliary Drainage., Cardiovascular and Interventional Radiology, Vol.40, No.6, 894-901, 2017.
(Summary)
To retrospectively evaluate the usefulness of virtual fluoroscopic preprocedural planning (VFPP) in the percutaneous transhepatic biliary drainage (PTBD) procedure. Twenty-two patients who were treated by PTBD were included in this study. Twelve patients were treated using PTBD intraoperative referencing coronal computed tomography (CT) images (i.e., coronal CT group), and ten patients were treated using PTBD intraoperative referencing VFPP images (i.e., VFPP group). To analyze the effect of the intraoperative referencing VFPP image, the VFPP group was retrospectively compared with the coronal CT group. The characteristics of both patient groups were not statistically significantly different. There were no significant differences in the targeted bile duct, diameter and depth of the target bile, breath-holding ability, number of targeted bile duct puncture attempts, change in the targeted bile duct, and exchange of the drainage catheter. However, the X-ray fluoroscopy time and the procedure time were significantly shorter in the VFPP group than in the coronal CT group (196 vs. 334 s, P < 0.05; and 16.0 vs. 27.2 min, P < 0.05). Intraoperative referencing using the VFPP imaging in PTBD intuitively can be a useful tool for better localization of the guidewire in the bile duct and thereby shorten the X-ray fluoroscopy time and procedure time while minimizing radiation exposure and complications.
We investigated whether administration of edaravone, a free radical scavenger, before or during tissue-type plasminogen activator (tPA) can enhance early recanalization in a major arterial occlusion. The YAMATO study (Tissue-Type Plasminogen Activator and Edaravone Combination Therapy) is an investigator-initiated, multicenter (17 hospitals in Japan), prospective, randomized, and open-label study. Patients with stroke secondary to occlusion of the M1 or M2 portion of the middle cerebral artery and within 4.5 hours of the onset were studied. The subjects were randomly allocated to the early group (intravenous edaravone [30 mg] was started before or during tPA) and the late group (edaravone was started after tPA and the assessment of early recanalization). One-hundred sixty-five patients (96 men; median age [interquartile range], of 78 [69-85] years) were randomized 1:1 to either the early group (82 patients) or the late group (83 patients). Primary outcome, defined as an early recanalization 1.5 hour after tPA, was observed in 53% of the early group and in 53% of the late group (P=1.000). About secondary outcomes, the rate of significant recanalization of ≥50% was not different between the 2 groups (28% versus 34%; P=0.393). The symptomatic intracerebral hemorrhage has occurred in 4 patients (5%) in the early group and in 2 patients (2%) in the late group (P=0.443). The favorable outcome (modified Rankin Scale score of 0-2) at 3 months was also similar between the groups (53% versus 57%; P=0.738). The timing of edaravone infusion does not affect the rate of early recanalization, symptomatic intracerebral hemorrhage, or favorable outcome after tPA therapy. URL: http://www.umin.ac.jp/ctr/index-j.htm. Unique identifier: UMIN000006330.
Hiroko Kubo, Masahito Nakataki, Satsuki Sumitani, Junichi Iga, Shusuke Numata, Naomi Kameoka, Shinya Watanabe, Hidehiro Umehara, Makoto Kinoshita, Masatoshi Inoshita, Mai Tamaru, Masashi Ohta, Chiaki Nakayama-Yamauchi, Yasuhiro Funakoshi, Masafumi Harada and Tetsuro Ohmori : 1H-magnetic resonance spectroscopy study of glutamate-related abnormality in bipolar disorder., Journal of Affective Disorders, Vol.208, 139-144, 2017.
(Summary)
Previous studies of patients with bipolar disorder (BD) using magnetic resonance spectroscopy (MRS) have shown neurophysiological abnormalities related to the glutamate (Glu)-glutamine (Gln) cycle, membrane turnover, and neuronal integrity, although the results were neither consistent nor conclusive. Recently it has been reported the Gln/Glu ratio is the most useful index, quantifying neuronal-glial interactions and the balance of glutamatergic metabolites In this MRS study, we elucidated the abnormalities of metabolites in a larger sample of patients with BD with a high-field MRI system. Sixty-two subjects (31 patients with BD and 31 healthy controls [HC]) underwent 3T proton MRS (1H-MRS) of the anterior cingulate cortex (ACC) and left basal ganglia (ltBG) using a stimulated echo acquisition mode (STEAM) sequence. After verifying the data quality, 20 patients with BD and 23 age- and gender-matched HCs were compared using repeated-measures analysis of covariance (ANCOVA). Compared to the HC group, the BD group showed increased levels of Gln, creatine (Cr), N-acetyl aspartate (NAA), choline (Cho), and an increased ratio of Gln to Glu in the ACC, and increased Gln and Cho in the ltBG. These findings remained after the participants with BD were limited to only euthymic patients. After removing the influence of lithium (Li) and sodium valproate (VPA), we observed activated glutamatergic neurotransmission in the ACC but not in the ltBG. The present findings are cross-sectional and metabolites were measured in only two regions. Our results support a wide range of metabolite changes in patients with BD involved in glutamatergic neurotransmission, membrane turnover, and neuronal integrity. Moreover, the elevation of Gln/Glu ratio suggested that hyperactivity of glutamatergic neurotransmission in the ACC is a disease marker for BD.
Aya Goji, Hiromichi Ito, Kenji Mori, Masafumi Harada, Sonoka Hisaoka, Yoshihiro Touda, Tatsuo Mori, Yoko Abe, Masahito Miyazaki and Shoji Kagami : Assessment of Anterior Cingulate Cortex (ACC) and Left Cerebellar Metabolism in Asperger's Syndrome with Proton Magnetic Resonance Spectroscopy (MRS)., PLoS ONE, No.1, e0169288, 2017.
(Summary)
Proton magnetic resonance spectroscopy (1H MRS) is a noninvasive neuroimaging method to quantify biochemical metabolites in vivo and it can serve as a powerful tool to monitor neurobiochemical profiles in the brain. Asperger's syndrome (AS) is a type of autism spectrum disorder, which is characterized by impaired social skills and restrictive, repetitive patterns of interest and activities, while intellectual levels and language skills are relatively preserved. Despite clinical aspects have been well-characterized, neurometabolic profiling in the brain of AS remains to be clear. The present study used proton magnetic resonance spectroscopy (1H MRS) to investigate whether pediatric AS is associated with measurable neurometabolic abnormalities that can contribute new information on the neurobiological underpinnings of the disorder. Study participants consisted of 34 children with AS (2-12 years old; mean age 5.2 (±2.0); 28 boys) and 19 typically developed children (2-11 years old; mean age 5.6 (±2.6); 12 boys) who served as the normal control group. The 1H MRS data were obtained from two regions of interest: the anterior cingulate cortex (ACC) and left cerebellum. In the ACC, levels of N-acetylaspartate (NAA), total creatine (tCr), total choline-containing compounds (tCho) and myo-Inositol (mI) were significantly decreased in children with AS compared to controls. On the other hand, no significant group differences in any of the metabolites were found in the left cerebellum. Neither age nor sex accounted for the metabolic findings in the regions. The finding of decreased levels of NAA, tCr, tCho, and mI in the ACC but not in left cerebellar voxels in the AS, suggests a lower ACC neuronal density in the present AS cohort compared to controls.
(Keyword)
Aspartic Acid / Asperger Syndrome / cerebellum / children / Child, Preschool / Choline / Creatine / Female / Gyrus Cinguli / Humans / Inositol / Male / Proton Magnetic Resonance Spectroscopy
Kenji Shono, Junichiro Satomi, Yoshiteru Tada, Yasuhisa Kanematsu, Nobuaki Yamamoto, Yuishin Izumi, Ryuji Kaji, Masafumi Harada and Shinji Nagahiro : Optimal Timing of Diffusion-Weighted Imaging to Avoid False-Negative Findings in Patients With Transient Ischemic Attack, Stroke, Vol.48, No.7, 1990-1992, 2017.
(Summary)
We aimed to investigate the optimal timing of diffusion-weighted imaging (DWI) in patients with transient ischemic attack (TIA). Seventy-three consecutive patients with TIA underwent DWI on admission (initial DWI) and at 24 hours after admission (second DWI). Patients were divided into 2 groups based on initial DWI findings in relation to the second examination: false negative (group 1) and other (group 2). The probability of initial false-negative findings was determined for each hour from TIA onset to initial DWI. Multivariate analysis was used to evaluate the independent risk factors associated with false-negative findings on initial DWI. Of the 73 patients examined (56 men; mean age, 68 years), 9 (12%) were categorized into group 1. The latency from TIA onset to initial DWI was 1.7±0.6 hours for group 1 (range, 1-2.8 hours) and 3.3±2.6 hours for group 2 (range, 35 minutes to 12 hours). The probability of false-negative findings on initial DWI decreased in a time-dependent manner (25%, 21%, and 7% for 1, 2, and 3 hours, respectively), and no false-negative findings were observed on initial DWI performed at >3 hours from symptom onset. Short latency (2 hours) from TIA onset to initial DWI was an independent risk factor related to false-negative findings (odds ratio, 13.11; 95% confidence interval, 1.07-161.38; P=0.045). If the duration between TIA symptom onset and initial DWI is <2 hours, a repeat examination should be performed to minimize the risk of false-positive findings.
(Keyword)
Aged / Aged, 80 and over / Diffusion Magnetic Resonance Imaging / False Negative Reactions / Female / Humans / Ischemic Attack, Transient / Male / Middle Aged / Retrospective Studies / Risk Factors / Sensitivity and Specificity / Time Factors
Mungunbagana Ganbold, Masafumi Harada, Delgerdalai Khashbat, Takashi Abe, Teruyoshi Kageji and Shinji Nagahiro : Differences In High-Intensity Signal Volume Between Arterial Spin Labeling And Contrast-Enhanced T1-Weighted Imaging May Be Useful For Differentiating Glioblastoma From Brain Metastasis, The Journal of Medical Investigation : JMI, Vol.64, No.1.2, 58-63, 2017.
(Summary)
To determine whether differences in tumor volume between arterial spin labeling (ASL) and contrast-enhanced T1-weighted MR images (CE+T1WI) can help differentiate glioblastoma (GBM) from brain metastasis. Patients with a diagnosis of GBM (n=25) or brain metastasis (n=13) were examined by both conventional and ASL MR imaging. Volumes of interest with high signal intensity on ASL and CE+T1WI were defined using three dimensional analysis software. Tumor volume difference (ASL-CE) and tumor volume ratio (ASL/CE) were obtained. Absolute maximal tumor blood flow (TBF) and TBF ratio (normalized to white matter) were also measured. The Mann-Whitney U test and receiver operating characteristic curve analysis were performed to compare measurements between the tumor groups. Both tumor volume difference and tumor volume ratio were significantly higher in GBM than in metastasis. Both TBF and TBF ratio were higher for GBM than for metastasis, but the differences were not significant. The difference in tumor volume as measured by ASL high signal intensity and CE+T1WI might be useful for differentiating GBM from metastasis, whereas ASL-derived TBF is insufficient. J. Med. Invest. 64: 58-63, February, 2017.
Takashi Abe, Toshitaka Kawarai, Koji Fujita, Wataru Sako, Yuka Terasawa, Tsuyoshi Matsuda, Waka Sakai, Ai Tsukamoto-Miyashiro, Naoko Matsui, Yuishin Izumi, Ryuji Kaji and Masafumi Harada : MR Spectroscopy in Patients with Hereditary Diffuse Leukoencephalopathy with Spheroids and Asymptomatic Carriers of Colony-stimulating Factor 1 Receptor Mutation., Magnetic Resonance in Medical Sciences, Vol.16, No.4, 297-303, 2016.
(Summary)
Hereditary diffuse leukoencephalopathy with spheroids (HDLS) is a rare neurodegenerative disorder with various clinical presentations. Mutation of the colony-stimulating factor 1 receptor (CSF1R) gene is considered to be a cause of this autosomal dominant disorder. The purpose of this study was to report magnetic resonance spectroscopy (MRS) findings in patients with HDLS and asymptomatic carriers and to clarify the use of MRS in this disease. In this retrospective, institutional review board-approved study, we included four consecutive patients, genetically diagnosed with HDLS, and two asymptomatic carriers after acquiring informed consent. We performed single-voxel MRS of the left centrum semiovale on a 3-T clinical scanner. We also included a sex-matched normal dataset. We quantified N-acetylaspartate (NAA), creatine, choline-containing compounds (Cho), glutamine, glutamate (Glu), myo-inositol (Ins), glutathione, lactate (Lac), and gamma-amino butyric acid using LCModel. We performed statistical analysis, and P value <0.05 was considered significant. In HDLS cases, MRS revealed decreased NAA and Glu concentrations, which probably reflected neuronal damage and/or loss, and a subsequent reduction of neurotransmitters. A patient with HDLS also had increased Cho and Ins concentrations, indicating gliosis, and increased Cho concentration was also observed in an asymptomatic carrier. This suggests that metabolic changes had already occurred in an asymptomatic state. We demonstrated changes in metabolite concentrations not only in patients with HDLS but also in asymptomatic CSF1R mutation carriers. Our study indicates that MRS is a potentially useful tool for the analysis of metabolic and pathophysiological findings of HDLS, even during the early stages of disease.
Tsuyoshi Honda, Takuro Baba, Keiko Fujimoto, Takaharu Goto, Kan Nagao, Masafumi Harada, Eiichi Honda and Tetsuo Ichikawa : Characterization of Swallowing Sound: Preliminary Investigation of Normal Subjects, PLoS ONE, Vol.11, No.12, e0168187, 2016.
(Summary)
The purpose of this study was to characterize the swallowing sound and identify the process of sound generation during swallowing in young healthy adults. Thirty-three healthy volunteers were enrolled and allocated into three experimental groups. In experiment 1, a microphone was attached to one of eight cervical sites in 20 subjects, participants swallowed 5 ml water, and the sound waveform was recorded. In experiment 2, 10 subjects swallowed either 0, 5, 10, or 15 ml water during audio recording. In addition, participants consumed the 5 ml bolus in two different cervical postures. In experiment 3, the sound waveform and videofluoroscopy were simultaneously recorded while the three participants consumed 5 ml iopamidol solution. The duration and peak intensity ratio of the waveform were analyzed in all experimental groups. The acoustic analysis of the waveforms and videofluoroscopy suggested that the swallowing sound could be divided into three periods, each associated with a stage of the swallowing movement: the oral phase comprising posterior tongue and hyoid bone movement; the pharyngeal phase comprising larynx movement, hyoid bone elevation, epiglottis closure, and passage of the bolus through the esophagus orifice; and the repositioning phase comprising the return of the hyoid bone and larynx to their resting positions, and reopening of the epiglottis. Acoustic analysis of swallowing sounds and videofluoroscopy suggests that the swallowing sound could be divided into three periods associated with each process of the swallowing movement: the oral phase comprising the posterior movement of the tongue and hyoid bone; the pharyngeal phase comprising the laryngeal movement, hyoid bone elevation, epiglottis closure, and the bolus passage to the esophagus orifice; and the repositioning phase comprising the repositioning of the hyoid bone and larynx, and reopening of the epiglottis.
Mitsuhiro Kinoshita, Katsuya Takechi, Seiji Iwamoto, Shoichiro Takao, Ryozo Shirono and Masafumi Harada : The usefulness of cone-beam computed tomography during chemoembolization of hepatocellular carcinomas fed exclusively by the cystic artery., Japanese Journal of Radiology, Vol.34, No.11, 747-753, 2016.
(Summary)
To evaluate the usefulness of cone-beam computed tomography (CBCT) for monitoring the transcatheter arterial chemoembolization (TACE) of hepatocellular carcinomas supplied by the cystic artery. In seven tumors (mean diameter: 19 mm), the iodized oil distributions in the tumor and gallbladder wall were evaluated by CBCT after injecting iodized oil emulsion (LipCBCT) through the cystic artery. Gelatin sponge particles were injected to completely obstruct the tumor-feeding vessel when iodized oil deposition was seen in less than one third of the wall circumference. The following parameters were retrospectively investigated: (1) the iodized oil distribution during LipCBCT and on CT scans 1 week after TACE; (2) local tumor control; and (3) complications. LipCBCT showed iodized oil accumulation throughout the entire tumor in all cases, and iodized oil deposition in the gallbladder wall in three cases (43 %) (less than one third of the circumference). Therefore, gelatin sponge particles were used in all cases. CT 1 week after TACE showed an almost identical iodized oil distribution to intraoperative LipCBCT. None of the tumors recurred during follow-up, and no complications occurred. CBCT is useful for evaluating the distribution of iodized oil in TACE via the cystic artery.
(Keyword)
Aged / Aged, 80 and over / Carcinoma, Hepatocellular / Chemoembolization, Therapeutic / Cone-Beam Computed Tomography / Female / Humans / Liver Neoplasms / Male / Treatment Outcome
Delgerdalai Khashbat, Takashi Abe, Mungunbagana Ganbold, Seiji Iwamoto, Naoto Uyama, Saho Irahara, Youichi Otomi, Masafumi Harada, Teruyoshi Kageji and Shinji Nagahiro : Correlation of 3D Arterial Spin Labeling and Multi-Parametric Dynamic Susceptibility Contrast Perfusion MRI in Brain Tumors., The Journal of Medical Investigation : JMI, Vol.63, No.3-4, 175-181, 2016.
(Summary)
Arterial spin labeling (ASL) is an alternative method to Dynamic susceptibility contrast (DSC) perfusion MRI for brain tumors. However, ASL cerebral blood flow (CBF) can be easily affected by transit time. DSC MRI derived time to maximum of the residue function (Tmax) is possible to assess the transit time on ASL. Thirty patients with brain tumors were studied using ASL and DSC MRI. The relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), Tmax, and mean transit time (MTT) were obtained from DSC MRI. The ratios of the parameters were analyzed. ASL CBF ratio correlated with the DSC rCBF ratio (r=0.78, p<0.001) and rCBV ratio (r=0.74, p<0.001). There was a moderate correlation between ASL CBF ratio and Tmax ratio (r=-0.43, p<0.05) in brain tumors. ASL CBF strongly correlated with DSC rCBF and rCBV. In addition, a negative correlation was found between ASL CBF and Tmax in brain tumors, indicating that these parameters would be affected by transit time. This may explain why ASL CBF is different from DSC rCBF and rCBV. The decreased DSC Tmax value may suggest high vascularity in a tumor. J. Med. Invest. 63: 175-181, August, 2016.
Youichi Otomi, Takayoshi Shinya, Hideki Otsuka, Terazawa Kaori, Irahara Saho, Nagase Saki, Takahashi Ayaka, Michiko Kubo and Masafumi Harada : Increased (18)F-fluorodeoxyglucose accumulation in bilateral adrenal glands of the patients suffering from vasovagal reaction due to blood vessel puncture., Annals of Nuclear Medicine, Vol.30, No.7, 501-505, 2016.
(Summary)
The purpose of the study was to evaluate the hypothesis that patients having a vasovagal reaction (VVR) after blood vessel puncture show increased FDG accumulation in bilateral adrenal glands. Over the past 8 years, 26 patients experienced a VVR after blood vessel puncture following intra-venous injection of FDG at our institution. Of the 26 patients, 16 underwent multiple-occasion FDG-PET/CT scans while suffering a VVR at only one examination. All 16 patients had no morphological abnormality in the adrenal glands on FDG-PET/CT and follow-up examination. For the 16, we retrospectively reviewed the FDG-PET/CT scan with respect to the adrenal glands and compared the result to that for the FDG-PET/CT scan of the same patient when there was no VVR event. We used both visual analysis and semi-quantitative analysis employing either maximum standardized uptake value (SUVmax) or adrenal-to-liver (A/L) SUVmax ratio. On visual analysis of the FDG-PET/CT with VVR, accumulations in both of the adrenal glands was judged positive, defined as higher than the hepatic accumulation, in 84 % of the cases. The SUVmax in the right adrenal gland was 2.79 ± 0.69 with VVR and 1.92 ± 0.33 without VVR; this value in the left adrenal gland was 3.07 ± 0.71 with VVR and 2.05 ± 0.39 without. Mean SUVmax of both adrenal glands was 2.93 ± 0.66 with VVR and 1.98 ± 0.35 without. The A/L SUVmax ratio in the right adrenal gland was 1.02 ± 0.26 with VVR and 0.69 ± 0.11 without; this value in the left was 1.11 ± 0.23 with VVR and 0.74 ± 0.15 without. The mean A/L SUVmax ratio of both adrenal glands was 1.06 ± 0.24 with VVR and 0.72 ± 0.13 without. Each parameter with VVR was significantly higher than that without. For the two adrenal glands, the mean SUVmax with VVR was 48 % higher than that without VVR. We confirmed the hypothesis that patients having a VVR after blood vessel puncture show increased FDG accumulation in their bilateral adrenal glands. This may reflect hyper-metabolism of the adrenal glands in synthesizing and secreting catecholamine.
Wataru Sako, Takashi Abe, Nagahisa Murakami, Yoshimichi Miyazaki, Yuishin Izumi, Masafumi Harada and Ryuji Kaji : Imaging-based differential diagnosis between multiple system atrophy and Parkinson's disease., Journal of the Neurological Sciences, Vol.368, 104-108, 2016.
(Summary)
There are many tools for differentiating between multiple system atrophy with predominant parkinsonian features (MSA-P) and Parkinson's disease (PD). These include middle cerebellar peduncle (MCP) width, apparent diffusion coefficient (ADC) value of the putamen and cerebellum, and (123)I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy images. We aimed to directly compare the above-mentioned methods, and to determine the optimal tool for differential diagnosis. Eleven patients with MSA-P and 36 patients with PD were enrolled. Of these, 7 patients with MSA-P and 14 patients with PD were chosen as background-matched subjects. We measured MCP width, ADC value of the putamen and cerebellum, and MIBG myocardial scintigraphy images. Area under curve (AUC) of receiver operating characteristic (ROC) was assessed to compare the above-mentioned methods. MCP width and ADC value of the putamen may be helpful for differentiating between MSA-P and PD relative to other methods in background-matched patients (MCP, AUC=0.95; putamen ADC, AUC=0.88; cerebellar ADC, AUC=0.70; MIBG, AUC=0.78). Similar AUCs were seen in all patients with different backgrounds. Our findings suggested that MCP width and ADC value of the putamen could be superior to ADC value of the cerebellum and MIBG uptake for differentiating between MSA-P and PD.
(Keyword)
Area Under Curve / cerebellum / Diagnosis, Differential / Female / Humans / Male / Middle Aged / Middle Cerebellar Peduncle / Multiple System Atrophy / Parkinson's disease / Putamen / ROC Curve
Mungunkhuyag Majigsuren, Takashi Abe, Teruyoshi Kageji, Kazuhito Matsuzaki, Mayumi Takeuchi, Seiji Iwamoto, Youichi Otomi, Naoto Uyama, Shinji Nagahiro and Masafumi Harada : Comparison of brain tumor contrast-enhancement on T1-CUBE and 3D-SPGR images, Magnetic Resonance in Medical Sciences, Vol.15, No.1, 34-40, 2016.
(Summary)
T1-Cube (GE HealthCare) is a relatively new 3-dimensional (3D) fast spin-echo (FSE)-based magnetic resonance (MR) imaging sequence that uses a variable flip angle to acquire gap-free volume scans. We compared the gadolinium enhancement characteristics of a heterogeneous population of brain tumors imaged by T1-Cube and then 3D fast spoiled gradient recall acquisition in steady state (3D FSPGR) 3-tesla MR imaging to identify the superior modality for specific diagnostic purposes. We examined 61 lesions from 32 patients using the 2 sequences after administration of gadopentetic acid (Gd-DTPA; 0.1 mmol/kg). Two neuroradiologists independently measured each lesion twice using a region-of-interest (ROI) method. We measured the contrast-to-noise ratio (CNR), the difference in signal intensity (SI) between the tumor and normal white matter relative to the standard deviation (SD) of the SI within the lesion, for both post-contrast 3D FSPGR and post-contrast T1-Cube images of the same tumor and compared modality-specific CNRs for all tumors and in subgroups defined by tumor size, enhancement ratio, and histopathology. The mean CNR was significantly higher on T1-Cube images than 3D FSPGR images for the total tumor population (1.85 ± 0.97 versus 1.12 ± 1.05, P < 0.01) and the histologic types, i.e., metastasis (P < 0.01) and lymphoma (P < 0.05). The difference in CNR was even larger for smaller tumors in the metastatic group (4.95 to 23.5 mm(2)) (P < 0.01). In contrast, mean CNRs did not differ between modalities for high grade glioma and meningioma. Gadolinium enhancement of brain tumors was generally higher when imaged by T1-Cube than 3D FSPGR, and T1-Cube with Gd enhancement may be superior to 3D FSPGR for detecting smaller metastatic tumors.
(Keyword)
Adult / Aged / Aged, 80 and over / Astrocytoma / Brain Neoplasms / Contrast Media / Female / Gadolinium DTPA / Humans / Image Enhancement / Image Processing, Computer-Assisted / Imaging, Three-Dimensional / Lymphoma, Large B-Cell, Diffuse / magnetic resonance imaging / Male / Meningioma / Middle Aged / Oligodendroglioma / Signal-To-Noise Ratio / White Matter
Our purpose in this study was to reduce the noise in order to improve the SNR of Dw images with high b-value by using two correction schemes. This study was performed with use of phantoms made from water and sucrose at different concentrations, which were 10, 30, and 50 weight percent (wt%). In noise reduction for Dw imaging of the phantoms, we compared two correction schemes that are based on the Rician distribution and the Gaussian distribution. The highest error values for each concentration with use of the Rician distribution scheme were 7.3 % for 10 wt%, 2.4 % for 30 wt%, and 0.1 % for 50 wt%. The highest error values for each concentration with use of the Gaussian distribution scheme were 20.3 % for 10 wt%, 11.6 % for 30 wt%, and 3.4 % for 50 wt%. In Dw imaging, the noise reduction makes it possible to apply the correction scheme of Rician distribution.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Clinical application of susceptibility-weighted MR sequences in the female pelvis, Proc. Intl. Soc. Mag. Reson. Med., Vol.24, 3884, 2016.
139.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Computed diffusion-weighted imaging for differentiating decidualized endometrioma from ovarian cancer, European Journal of Radiology, Vol.85, No.5, 1016-1019, 2016.
(Summary)
To evaluate the clinical diagnostic ability of computed diffusion-weighted imaging (DWI) for differentiating decidualized endometrioma from ovarian cancer. Computed DWI technique was retrospectively applied to 20 mural nodules in 9 decidualized endometriomas during pregnancy and 20 ovarian cancers. Signal intensities on measured DWI with b values of 800s/mm(2) (DWI800) and on computed DWI with b values of 1500s/mm(2) (cDWI1500) were visually evaluated. Mural nodules of all decidualized endometriomas showed high signal intensity on DWI800 with significantly higher ADC (2.01±0.26×10(-3)mm(2)/s) and low signal intensity on cDWI1500, whereas solid components of all ovarian cancers showed high signal intensity on both DWI800 with lower ADC (1.08±0.20×10(-3)mm(2)/s) and on cDWI1500. Mural nodules in decidualized endometriomas may show high signal intensity on DWI800 due to T2 shine-through effect, and cDWI1500 can distinguish decidualized endometriomas from ovarian cancers by visual evaluation.
Yuki Kanazawa, Yuki Matsumoto, Hiroaki Hayashi, Tsuyoshi Matsuda, Munguu Ganbold and Masafumi Harada : Simple improvement method of uniformity of MR elastography on liver, Proceedings of the 24th Annual Meeting of ISMRM, 2972, 2016.
141.
Mayumi Takeuchi, Kenji Matsuzaki, Yoshimi Bando, Masato Nishimura, Akiko Yoneda and Masafumi Harada : A case of polypoid endometriosis with malignant transformation., Abdominal Radiology, Vol.41, No.9, 1699-1702, 2016.
(Summary)
Polypoid endometriosis is a benign, rare variant of endometriosis which forms multiple polypoid nodules in the female pelvis mimicking malignant tumors; however, it may rarely cause malignant transformation. We report magnetic resonance imaging findings of a case of polypoid endometriosis with malignant transformation. Multiple high-signal intensity polypoid nodules in the cul-de-sac surrounded by low-signal intensity rim-like fibrous adhesion protruding to the posterior wall of the uterine body were demonstrated on T2-weighted images. The polypoid nodules showed weak contrast enhancement compared with that of uterine myometrium on post-contrast T1-weighted images, and slight high signal intensity on diffusion-weighted images with relatively high mean apparent diffusion coefficient. Reported cases of polypoid endometriosis showed intense contrast enhancement similar to that of uterine myometrium, and weak contrast enhancement similar to that of endometrial carcinoma may be suggestive for malignant transformation of polypoid endometriosis.
Wataru Sako, Takashi Abe, Yuishin Izumi, Masafumi Harada and Ryuji Kaji : Fractional anisotropy in the supplementary motor area correlates with disease duration and severity of amyotrophic lateral sclerosis., Neurological Sciences, Vol.37, No.4, 573-577, 2016.
(Summary)
Amyotrophic lateral sclerosis (ALS) is progressive and fatal neurodegenerative disorder with upper and lower motor neuron signs. There are no biomarkers to track disease progression. To address this issue, we investigated regions in which fractional anisotropy (FA) values derived from diffusion weighted images correlated with both disease severity and duration in ALS patients. Fourteen patients with ALS were enrolled in this study. Voxel-based analysis revealed volume of interests (VOIs) showing significant correlation. Finally, Spearman rank correlation coefficient was assessed between FA value in each VOI and disease severity or duration. In the VOI of left supplementary motor area (SMA), FA value significantly correlated with disease severity and duration both (disease severity, rho = 0.59, p = 0.025; disease duration, rho = -0.69, p = 0.006). The present finding suggested the possibility that the abnormality in motor-related region including SMA could be a candidate for a biomarker to track disease progression.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Carcinosarcoma of the uterus: MRI findings including diffusion-weighted imaging and MR spectroscopy., Acta Radiologica, Vol.57, No.10, 1277-1284, 2016.
(Summary)
Recently carcinosarcoma has become regarded as a subset of endometrial carcinoma. Because the clinical course of carcinosarcoma is aggressive with poor prognosis, it should be differentiated from endometrial carcinomas for the appropriate surgical management and adjuvant therapy. To clarify the magnetic resonance imaging (MRI) characteristics of uterine carcinosarcoma including diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) measurement and MR spectroscopy (MRS) with quantitative metabolite evaluation. MRI findings of 12 pathologically diagnosed uterine carcinosarcomas obtained on 3T MRI were retrospectively evaluated. The mean and minimum ADCs, and the lipid and choline concentration levels were compared with those of pathologically diagnosed 38 endometrial carcinomas. The mean and minimum ADCs in carcinosarcomas and endometrial carcinomas were not significantly different. The mean ADC of carcinosarcomas was significantly higher than that of higher grade (G2 and G3) endometrial carcinomas. The choline concentration in carcinosarcomas was significantly lower than that in endometrial carcinomas. High lipid peak was observed in 91% of carcinosarcomas and in 24% of endometrial carcinomas. Large, exophytic heterogeneous endometrial mass containing strongly enhanced areas, which may exhibit "tumor delivery", is a suggestive of carcinosarcoma. Relatively high mean ADC and low choline concentration considering its highly malignant nature due to intra-tumoral heterogeneity with necrosis and epithelial cystic components, and the presence of necrosis-associated high lipid peak may be compatible with carcinosarcoma.
Wataru Sako, Takashi Abe, Yuishin Izumi, Masafumi Harada and Ryuji Kaji : The ratio of N-acetyl aspartate to glutamate correlates with disease duration of amyotrophic lateral sclerosis, Journal of Clinical Neuroscience, Vol.27, 110-113, 2016.
(Summary)
Glutamate (Glu)-induced excitotoxicity has been implicated in the neuronal loss of amyotrophic lateral sclerosis. To test the hypothesis that Glu in the primary motor cortex contributes to disease severity and/or duration, the Glu level was investigated using MR spectroscopy. Seventeen patients with amyotrophic lateral sclerosis were diagnosed according to the El Escorial criteria for suspected, possible, probable or definite amyotrophic lateral sclerosis, and enrolled in this cross-sectional study. We measured metabolite concentrations, including N-acetyl aspartate (NAA), creatine, choline, inositol, Glu and glutamine, and performed partial correlation between each metabolite concentration or NAA/Glu ratio and disease severity or duration using age as a covariate. Considering our hypothesis that Glu is associated with neuronal cell death in amyotrophic lateral sclerosis, we investigated the ratio of NAA to Glu, and found a significant correlation between NAA/Glu and disease duration (r=-0.574, p=0.02). The "suspected" amyotrophic lateral sclerosis patients showed the same tendency as possible, probable and definite amyotrophic lateral sclerosis patients in regard to correlation of NAA/Glu ratio with disease duration. The other metabolites showed no significant correlation. Our findings suggested that glutamatergic neurons are less vulnerable compared to other neurons and this may be because inhibitory receptors are mainly located presynaptically, which supports the notion of Glu-induced excitotoxicity.
Shunya Nakane, Kaori Furutani, Masafumi Harada, Ryo Urushihara, Naoko Matsui, Yuishin Izumi and Ryuji Kaji : Multimodal analysis based on high-field magnetic resonance and motor evoked potentials: A case report of multiple sclerosis, Clinical & Experimental Neuroimmunology, Vol.8, No.1, 43-46, 2016.
Yuto Konishi, Yuki Kanazawa, Takatoshi Usuda, Yuki Matsumoto, Hiroaki Hayashi, Tsuyoshi Matsuda and Masafumi Harada : Comparison with statistical analysis of signal correction in diffusion weighted MR image, European Congress of Radiology (EPOS), C-0291, 2016.
Nobuaki Yamamoto, Junichiro Satomi, Yamamoto Yuki, Takahiro Furukawa, Yoshiteru Tada, Masafumi Harada, Shinji Nagahiro and Ryuji Kaji : The susceptibility vessel sign containing two compositions on 3-tesla T2*-weighted image and single corticosubcortical infarct on diffusion-weighted image are associated with cardioembolic stroke, Journal of the Neurological Sciences, Vol.359, No.1-2, 141-145, 2015.
(Summary)
Although accurate diagnosis of the ischemic stroke subtype is one of the most important factors for selection of therapeutic approach, it is sometimes difficult at the time of admission. We previously reported that susceptibility vessel sign (SVS) with two layers (termed two-layered SVS) on 3-tesla-T2*-weighted image (T2*-WI) might be useful to predict cardioembolic stroke in patients with cerebral major vessel occlusion. We studied about biomarkers on magnetic resonance imaging (MRI), including two-layered SVS for diagnosing cardioembolic stroke. We included 132 ischemic stroke patients within 24h from onset who suffered internal carotid artery or middle cerebral artery occlusion due to cardioembolic stroke (group CE) or large artery atherosclerosis (group LAA). We studied about biomarkers on MRI such as two-layered SVS and abnormal finding patterns of diffusion-weighted image (DWI) for diagnosis of cardioembolic stroke in addition to laboratory data, physiological examination, and clinical findings. In this study, 132 patients (72 men and 60 women, age 74.5 ± 12.1 years) were included. Of these, 63 (47.7%) were cardioembolic stroke. In univariate analysis, frequency of comorbid atrial fibrillation, presence of two-layered SVS on T2*-WI and that of single corticosubcortical infarct on DWI, intima-media thickness were significantly higher in group CE. In multivariate analysis, the presence of two-layered SVS and single corticosubcortical infarct were associated with cardioembolic stroke (odds ratio, two-layered SVS, 30.08, p<0.001; single corticosubcortical infarct, 15.78, p<0.001). Biomarkers associated with cardioembolic stroke may be two-layered SVS on T2*-WI and single corticosubcortical infarct on DWI.
Yuki Kanazawa, Hiroaki Hayashi and Masafumi Harada : Clinical Approach of T1-mapping for Hemodynamic Analysis, Medical Imaging and Information Sciences, Vol.32, No.4, xxvi-xxix, 2015.
Motoharu Sasaki, Hitoshi Ikushima, Masahide Tominaga, T Kamomae, T Kishi, Masataka Oita and Masafumi Harada : Dose impact of rectal gas on prostatic IMRT and VMAT, Japanese Journal of Radiology, Vol.33, No.12, 723-733, 2015.
(Summary)
In this study, we compared the dose impact of the heterogeneity caused by rectal gas using two methods of treatment planning for intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT). In addition to the structure set used for the standard treatment plan, we created a structure set for evaluation for each patient. These sets were transferred to the same isocenter as the respective treatment plans for IMRT and VMAT that were to become the standard. Values were then recalculated. During the standard prostatic IMRT and VMAT treatment planning, all study participants met dose restrictions in place at our hospital. Dose restrictions were fulfilled in treatment plans for evaluation, excluding those with a clinical target volume (CTV) of V(100%) and planning target volume (PTV) of D95 when the rectum was excluded. However, in treatment plans for evaluation, IMRT was shown to have a higher concordance rate with standard treatment plans than VMAT. If rectal gas is present during either IMRT or VMAT, a dose decrease will occur in relation to CTV and PTV, suggesting that a plan does not eliminate adverse effects on organs at risk.
Wataru Sako, Nagahisa Murakami, Yoshimichi Miyazaki, Takashi Abe, Masafumi Harada, Yuishin Izumi and Ryuji Kaji : The effect of tremor onset on middle cerebellar peduncle of Parkinson's disease., Journal of the Neurological Sciences, Vol.358, No.1-2, 172-177, 2015.
(Summary)
The majority of studies of Parkinson's disease (PD) focused on basal ganglia initially; however, accumulating evidence suggests cerebellar involvement in pathophysiology. We aimed to investigate the effects of tremor onset on middle cerebellar peduncle (MCP) width of PD patients and of disease duration on differential diagnosis. We measured MCP width of 81 PD, 34 multiple system atrophy (MSA) and 16 normal controls, using MRI. A meta-analysis was performed including two previous and the present studies. We carried out correlation analysis between disease duration and MCP width separately in subgroup of PD with or without tremor onset. Receiver operating characteristic curves were analyzed. Our meta-analysis indicated that MCP width was significantly smaller in MSA relative to PD with homogeneous studies. There was significant correlation between disease duration and MCP width in PD without tremor onset. In contrast, there was no correlation observed in PD with tremor onset. Subclassification according to disease duration showed improved area under curve of PD vs. MSA with predominant parkinsonian features. MCP width could be a valuable tool for differential diagnosis. Our finding suggested that MCP was impaired in advanced stage of PD without tremor onset as part of the abnormality of the cerebellar system.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : MR manifestations of uterine polypoid adenomyoma, Abdominal Imaging, Vol.40, No.3, 480-487, 2015.
(Summary)
Polypoid adenomyoma (PA) is an uncommon benign tumor of the uterus appearing as a submucosal polypoid mass, or rarely as a subserosal polypoid mass. PA should be differentiated from atypical polypoid adenomyoma or malignant uterine tumors. The purpose of our case series is to evaluate magnetic resonance (MR) manifestations of PA for the differential diagnosis. Seven cases with surgically proven PA, five submucosal, and two subserosal, were evaluated. MR imaging findings including contrast enhancement in six cases (four cases with dynamic contrast-enhanced MR study), diffusion-weighted imaging (DWI) in five cases, and susceptibility weighted imaging (SWI) in two cases were retrospectively reviewed. All seven lesions exhibited isointensity compared with the myometrium and 4 of 7 lesions (57%) contained high signal intensity hemorrhagic areas on T1-weighted images. On T2-weighted images, signal intensity was variable and all seven lesions contained cysts. None of five lesions with DWI exhibited high signal intensity compared with the normal myometrium. All six lesions showed intense contrast enhancement similar to that of the myometrium on post-contrast T1-weighted images. Punctate low intensity areas reflecting blood contents were revealed in all two lesions with SWI. Submucosal or subserosal polypoid masses containing hemorrhagic areas, and cysts reflecting functional endometrium and dilatation of endometrial glands are suggestive for PA. Intense contrast enhancement similar to that of the myometrium may be another characteristic finding for PA.
Takashi Abe, Yoshifumi Mizobuchi, Kohhei Nakajima, Youichi Otomi, Saho Irahara, Yuki Obama, Mungunkhuyag Majigsuren, Delgerdalai Khashbat, Teruyoshi Kageji, Shinji Nagahiro and Masafumi Harada : Diagnosis of brain tumors using dynamic contrast-enhanced perfusion imaging with a short acquisition time, SpringerPlus, Vol.24, No.4, 88, 2015.
(Summary)
This study sought to determine the diagnostic utility of perfusion parameters derived from dynamic contrast-enhanced (DCE) perfusion MRI with a short acquisition time (approximately 3.5 min) in patients with glioma, brain metastasis, and primary CNS lymphoma (PCNSL). Twenty-six patients with 29 lesions (4 low-grade glioma, 13 high-grade glioma, 7 metastasis, and 5 PCNSL) underwent DCE-MRI in a 3 T scanner. A ROI was placed on the hotspot of each tumor in maps for volume transfer contrast K (trans) , extravascular extracellular volume V e , and fractional plasma volume V p . We analyzed differences in parameters between tumors using the Mann-Whitney U test. We calculated sensitivity and specificity using receiver operating characteristics analysis. Mean K (trans) values of LGG, HGG, metastasis and PCNSL were 0.034, 0.31, 0.38, 0.44, respectively. Mean Ve values of each tumors was 0.036, 0.57, 0.47, 0.96, and mean Vp value of each tumors was 0.070, 0.086, 0.26, 0.17, respectively. Compared with other tumor types, low-grade glioma showed lower K (trans) (P < 0.01, sensitivity = 88%, specificity = 100%) and lower V e (P < 0.01, sensitivity = 96%, specificity = 100%). PCNSL showed higher V e (P < 0.01, sensitivity = 100%, specificity = 88%), but the other perfusion parameters overlapped with those of different histology. Kinetic parameters derived from DCE-MRI with short acquisition time provide useful information for the differential diagnosis of brain tumors.
Extra-ovarian endometriosis (EOE) usually appears as solid masses mimicking neoplasms both clinically and radiologically. Detection of blood products within a lesion may be suggestive of its endometriotic nature. We present a descriptive study of MR imaging findings that include susceptibility-weighted imaging (SWI) for patients with EOE. Eight pathologically proven EOE (3 bowel, 2 bladder and 3 abdominal wall) were evaluated. Fat-saturated T1-weighted images (fsT1WI) and SWI were obtained using 1.5T MR imaging. Images were reviewed for the presence of signal voids on SWI and of high-intensity foci on fsT1WI. High-intensity foci reflecting subacute hemorrhage were detected in 4 of 8 lesions (50%) on fsT1WI, whereas signal voids reflecting acute to chronic hemorrhage were detected in all 8 lesions (100%) on SWI. SWI is a sensitive MRI technique which demonstrates hemorrhage of varying chronicity in patients with EOE and may improve future MRI characterization of EOE.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Susceptibility-weighted Imaging of Ovarian Torsion: A Case Report, Magnetic Resonance in Medical Sciences, Vol.14, No.4, 355-358, 2015.
(Summary)
We report findings of magnetic resonance imaging including susceptibility-weighted imaging (SWI) of the subacute torsion of an ovarian fibrothecoma in a patient with renal dysfunction. Although venous thrombosis within the vascular pedicle mimicked a malignant tumor, showing high signal intensity on T2-weighted images and diffusion-weighted imaging, we diagnosed ovarian torsion on SWI without the administration of contrast medium, aided by the prominent susceptibility-induced signal void caused by the thrombosis.
Kenji Mori, Yoshihiro Touda, Hiromichi Ito, Tatsuo Mori, Keiko Mori, Aya Goji, Hiroko Hashimoto, Hiroe Tani, Masahito Miyazaki, Masafumi Harada and Shoji Kagami : Neuroimaging in autism spectrum disorders: 1H-MRS and NIRS study, The Journal of Medical Investigation : JMI, Vol.62, No.1-2, 29-36, 2015.
(Summary)
Using proton magnetic resonance spectroscopy ((1)H-MRS), we measured chemical metabolites in the left amygdala and the bilateral orbito-frontal cortex (OFC) in children with autism spectrum disorders (ASD). The concentrations of N-acetylaspartate (NAA) in these regions of ASD were significantly decreased compared to those in the control group. In the autistic patients, the NAA concentrations in these regions correlated with their social quotient. These findings suggest the presence of neuronal dysfunction in the amygdala and OFC in ASD. Dysfunction in the amygdala and OFC may contribute to the pathogenesis of ASD. We performed a near-infrared spectroscopy (NIRS) study to evaluate the mirror neuron system in children with ASD. The concentrations of oxygenated hemoglobin (oxy-Hb) were measured with frontal probes using a 34-channel NIRS machine while the subjects imitated emotional facial expressions. The increments in the concentration of oxy-Hb in the pars opercularis of the inferior frontal gyrus in autistic subjects were significantly lower than those in the controls. However, the concentrations of oxy-Hb in this area were significantly elevated in autistic subjects after they were trained to imitate emotional facial expressions. The results suggest that mirror neurons could be activated by repeated imitation in children with ASD.
Nobuaki Yamamoto, Junichiro Satomi, Masafumi Harada, Yuishin Izumi, Shinji Nagahiro and Ryuji Kaji : Is the Susceptibility Vessel Sign on 3-Tesla Magnetic Resonance T2*-Weighted Imaging a Useful Tool to Predict Recanalization in Intravenous Tissue Plasminogen Activator?, Clinical Neuroradiology, 2014.
(Summary)
The aim of this study was to investigate the independent factors associated with the absence of recanalization approximately 24 h after intravenous administration of tissue-type plasminogen activator (IV TPA). The previous studies have been conducted using 1.5-Tesla (T) magnetic resonance imaging (MRI). We studied whether the characteristics of 3-T MRI findings were useful to predict outcome and recanalization after IV tPA. Patients with internal carotid artery (ICA) or middle cerebral artery (MCA) (horizontal portion, M1; Sylvian portion, M2) occlusion and treated by IV tPA were enrolled. We studied whether the presence of susceptibility vessel sign (SVS) at M1 and low clot burden score on T2*-weighted imaging (T2*-CBS) on 3-T MRI were associated with the absence of recanalization. A total of 49 patients were enrolled (27 men; mean age, 73.9 years). MR angiography obtained approximately 24 h after IV tPA revealed recanalization in 21 (42.9 %) patients. Independent factors associated with the absence of recanalization included ICA or proximal M1 occlusion (odds ratio, 69.6; 95 % confidence interval, 5.05-958.8, p = 0.002). In this study, an independent factor associated with the absence of recanalization may be proximal occlusion of the cerebral arteries rather than SVS in the MCA or low T2*-CBS on 3-T MRI.
Nobuaki Yamamoto, Junichiro Satomi, Yoshiteru Tada, Masafumi Harada, Yuishin Izumi, Shinji Nagahiro and Ryuji Kaji : The two-1 layered susceptibility vessel sign on 3-tesla T2*-weighted imaging is a predictive biomarker of stroke subtype, Stroke, Vol.46, No.1, 269-271, 2014.
(Summary)
A susceptibility vessel sign (SVS) on 1.5-tesla (T)-T2*-weighted images may predict cardioembolism. It has also been detected in patients with large artery atherosclerosis. In patients with major vessel occlusion, the SVS was comprised 2 layers on 3T-T2*-weighted images. We assessed the efficacy of 2-layered SVS on 3T-T2*-weighted imaging scans for predicting cardioembolism. Our study included 132 patients who had ischemic stroke within the preceding 24 hours and presented with internal carotid artery or middle cerebral artery occlusion because of cardioembolism or large artery atherosclerosis. We compared 2-layered SVS and SVS on 3T-T2*-weighted imaging scans for their sensitivity, specificity, and diagnostic odds ratio for predicting cardioembolism. We enrolled 132 patients (72 men; mean age, 74.5 years); of these, 63 (47.7%) were presented with cardioembolism. Although the sensitivity of SVS and 2-layered SVS for cardioembolism and large artery atherosclerosis was not statistically different (74.6% and 58.0%, respectively), the sensitivity of 2-layered SVS was significantly higher in patients with cardioembolism (42.9%) than those with large artery atherosclerosis (2.9%; P<0.001). The specificity and diagnostic odds ratio for 2-layered SVS for cardioembolism were 97.1% and 25.1; for SVS they were 42.0% and 2.1, respectively. The specificity of 2-layered SVS for cardioembolism was high. It may be useful for predicting cardioembolism and for the management of patients with acute ischemic stroke.
Nobuaki Yamamoto, Yuka Terasawa, Junichiro Satomi, Sakai Waka, Masafumi Harada, Yuishin Izumi, Shinji Nagahiro and Ryuji Kaji : Predictors of neurologic deterioration in patients with small-vessel occlusion and infarcts in the territory of perforating arteries, Journal of Stroke & Cerebrovascular Diseases, Vol.23, No.8, 2151-2155, 2014.
(Summary)
It is difficult to predict neurologic deterioration in patients with small-vessel occlusion (SVO), that is, small infarcts in the territory of cerebral perforating arteries. We reviewed 110 patients with SVO who were admitted to our hospital. We divided them into groups with (n = 32, group 1) and without deterioration (n = 78, group 2) and evaluated their medical records, risk factors, magnetic resonance imaging findings, grade of periventricular hyperintensity (PVH), maximum diameter of the infarct area, and the number of slices showing infarcts on diffusion-weighted images (DWI). Our study population consisted of 110 patients (71 males and 39 females; mean age 69.2 years): 32 (29%) did and 78 (71%) did not suffer deterioration. By univariate analysis, the age, current smoking, history of stroke, maximum diameter of the infarcted area, number of DWI slices with infarcts, frequency of PVH, and PVH grade based on Fazekas classification differed significantly between the 2 groups. By multivariate analysis, conventional risk factors other than PVH and history of stroke were not associated with neurologic deterioration (PVH grade ≥ 2 versus PVH grade ≤ 1, odds ratio 6.72, P = .006; with stroke versus without stroke, odds ratio .21, P = .049). We also found that higher the PVH grade, the worse the National Institutes of Health Stroke Scale score at the time of discharge. PVH and without history of stroke are independently associated with neurologic deterioration in patients with SVO.
(Keyword)
Aged / Aged, 80 and over / Brain Infarction / Cerebral Arteries / Cerebral Ventricles / Diffusion Magnetic Resonance Imaging / Female / Humans / Intracranial Thrombosis / magnetic resonance imaging / Male / Middle Aged / Odds Ratio / Predictive Value of Tests / Risk Factors / smoking / PVH grade / neurologic deterioration / predictors / small vessel occlusion
Mayumi Takeuchi, Kenji Matsuzaki, Yoshimi Bando, Mika Sakaki, Hiroyuki Furumoto and Masafumi Harada : Magnetic Resonance Manifestations of Villoglandular Papillary Adenocarcinoma of the Uterine Cervix with a Fern-leaf-like Appearance., Magnetic Resonance in Medical Sciences, Vol.13, No.4, 267-270, 2014.
(Summary)
Villoglandular papillary adenocarcinoma (VGPA) is a rare subtype of cervical adenocarcinoma that generally affects young women and has a favorable prognosis. Its preoperative diagnosis is important to avoid excessive surgery. We report the magnetic resonance (MR) findings of a case in which the cervical tumor showed a fern-leaf-like appearance on high resolution T2-weighted images obtained at 3 tesla. MR imaging clearly showed this pathological feature that may suggest this disease.
(Keyword)
cervical cancer / MRI / uterus / villoglandular papillary adenocarcinoma
Teruyoshi Kageji, Shinji Nagahiro, Junichiro Satomi, Yuka Terasawa and Masafumi Harada : Evolution of Stroke Emergency System in Tokushima University Hospital, Japanese Journal of Stroke, Vol.36, No.3, 223-229, 2014.
(Summary)
We established the stroke care unit (SCU) for stroke emergency system in Tokushima University Hospital. There were 3,452 patients admitted with acute stroke from 1999 to 2013 in our institute, and 131 patients with acute ischemic stroke were treated with rt-PA (recombinant tissue-type plasminogen activator) intravenous infusion therapy. Revascularization therapy for acute ischemic stroke was done in 20% of patients and rt-PA intravenous infusion therapy in 10.6% of patients. SCU was on track since 2008 and the implementation rate of therapy during this period was 12.8%. The activity of stroke center in our institute promotes improvement of stroke medical level in the region, increase of convalescence rehabilitation facility, and increase in the hospital medical fees. As a result, the stroke center has contributed to medical students and young doctors for the education of stroke. Challenge for the future is the establishment of the treatment system for acute stroke in the medical depopulated area.
Yoshiteru Tada, Junichiro Satomi, Takashi Abe, Kazuyuki Kuwayama, Shu Sogabe, Koji Fujita, Nobuaki Yamamoto, Ryuji Kaji, Masafumi Harada and Shinji Nagahiro : Intra-arterial signal on arterial spin labeling perfusion MRI to identify the presence of acute middle cerebral artery occlusion, Cerebrovascular Diseases, Vol.38, No.3, 191-196, 2014.
(Summary)
The susceptibility vessel sign on gradient echo-type-T2*-weighted imaging is a well-known marker of arterial occlusion. Stagnant flow in front of the middle cerebral artery (MCA) occlusion sites may contribute to the intra-arterial, high-intensity signal on arterial spin labeling magnetic resonance imaging (MRI), making it another potential marker of MCA occlusion. We compared the intra-arterial, high-intensity signal and susceptibility vessel sign in patients with symptomatic MCA occlusion and patients without major vessel occlusion. We identified transient ischemic attack or ischemic stroke patients with (1) 3-T MRI performed within 24 h after clinical onset including arterial spin labeling, T2*-weighted imaging, and magnetic resonance angiography (MRA) and (2) either having MCA occlusion (n = 34 patients) or without major vessel occlusion (n = 24 patients). The intra-arterial, high-intensity signal was defined as an enlarged circular or linear bright hyperintensity within the artery. The susceptibility vessel sign was defined as an enlarged spot of hypointensity within the MCA, in which the diameter of the hypointense signal within the vessel exceeded the contralateral vessel diameter. The presence or absence of the intra-arterial, high-intensity signal and susceptibility vessel sign were assessed, along with their inter-rater agreement and consistency with the presence of MCA occlusion on MRA. The intra-arterial, high-intensity signal was detectable in 30 patients (52%), and susceptibility vessel sign was observed in 17 patients (29%). The sensitivity of the intra-arterial high-intensity signal was significantly higher than that of the susceptibility vessel sign (88% vs. 50%; p < 0.05). The accuracy of the intra-arterial high-intensity signal was also higher than that of the susceptibility vessel sign (93% vs. 71%; p < 0.05). The intra-arterial high-intensity signal was situated in the proximal regions of the susceptibility vessel sign on T2*WI within the MCA. Neither the intra-arterial high-intensity signal nor the susceptibility vessel sign was observed in patients without major vessel occlusion. Inter-rater agreement was good for intra-arterial high-intensity signal detection (κ = 0.73) and moderate for susceptibility vessel sign detection (κ = 0.47). The presence or absence of the intra-arterial high-intensity signal was highly consistent with that of MCA occlusion on MRA (κ = 0.74). The intra-arterial high-intensity signal on arterial spin labeling appears to be useful to identify the presence of acute MCA occlusion and may be associated with stagnant flow in front of occlusion sites. The intra-arterial high-intensity signal may also be used to identify the occlusion site.
(Keyword)
Aged / Aged, 80 and over / Cerebral Angiography / Female / Humans / Infarction, Middle Cerebral Artery / Ischemic Attack, Transient / Magnetic Resonance Angiography / magnetic resonance imaging / Male / Middle Aged / Middle Cerebral Artery / Sensitivity and Specificity / Stroke
Mungunkhuyag Majigusuren, Masafumi Harada, Takashi Abe, Koji Fujita, Naoko Matsui and Ryuji Kaji : Longitudinal Monitoring with Multiple MR Techniques in a Case of Progressive Multifocal Leukoencephalopathy Associated with Multiple Myeloma, Magnetic Resonance in Medical Sciences, Vol.13, No.1, 55-59, 2014.
(Summary)
Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the brain caused by the JC virus in immunocompromised patients. We report characteristic features of proton MR spectroscopy, 3-dimensional pseudo-continuous arterial spin labeling imaging, and diffusion tensor imaging in a 53-year-old patient with PML. The utility of multi-modal magnetic resonance techniques for longitudinal monitoring was indicated by their reevaluation over time and consideration of their relation to prognosis.
(Keyword)
Disease Progression / Humans / Leukoencephalopathy, Progressive Multifocal / Magnetic Resonance Imaging / Male / Middle Aged / Multiple Myeloma
Tatsuo Mori, Kenji Mori, Hiromichi Ito, Aya Goji, Masahito Miyazaki, Masafumi Harada, Kenji Kurosawa and Shoji Kagami : Age-related changes in a patient with Pelizaeus-Merzbacher disease determined by repeated 1H-magnetic resonance spectroscopy., Journal of Child Neurology, Vol.29, No.2, 283-288, 2014.
(Summary)
A boy with Pelizaeus-Merzbacher disease underwent repeated evaluations by 3-Tesla (1)H-magnetic resonance spectroscopy (MRS). The patient showed overlap of the PLP1. Individuals selected as normal controls for (1)H-magnetic resonance spectroscopy consisted of healthy age-matched children. For (1)H-magnetic resonance spectroscopy, the center of a voxel was positioned in the right parietal lobe. (1)H-magnetic resonance spectroscopy was performed when the patient was 2, 6, 14, and 25 months old. γ-Aminobutyric acid concentration in early childhood was increased compared with that in normal controls. However, the γ-aminobutyric acid concentration in the Pelizaeus-Merzbacher disease patient was normalized at 14 and 25 months. No remarkable changes were observed in choline-containing compounds concentration at any time. These results suggest that the changes in metabolite concentrations during growth can reflect the pathological condition of Pelizaeus-Merzbacher disease. Furthermore, the lack of change in the choline-containing compounds concentration can be useful for differentiating Pelizaeus-Merzbacher disease from other white matter disorders.
Yuka Terasawa, Nobuaki Yamamoto, Ryoma Morigaki, Koji Fujita, Yuishin Izumi, Junichiro Satomi, Masafumi Harada, Shinji Nagahiro and Ryuji Kaji : Brush sign on 3-T t2*-weighted MRI as a potential predictor of hemorrhagic transformation after tissue plasminogen activator therapy, Stroke, Vol.45, No.1, 274-276, 2014.
(Summary)
The brush sign (BS) is the enlargement of medullary veins on 3-T T2*-weighted MRI seen in patients with ischemic stroke because of major cerebral artery occlusion. However, the clinical relevance of BS in patients with acute stroke remains unclear. We assessed the correlation between detecting BS with the development of hemorrhagic transformation after intravenous thrombolysis. We enrolled consecutive patients with M1 or M2 occlusion treated with intravenous tissue plasminogen activator. We classified the patients into 2 groups: the group positive for BS (P-BS) and the group negative for BS (N-BS). We investigated the differences in MRI findings and the clinical outcome between the 2 groups. The subjects consisted of 36 patients (19 men; mean age, 74.7 years). Twenty-one patients (58%) had M1 occlusion, and 15 (42%) had M2 occlusion. Twenty-five patients (69%) were classified into the P-BS group and 11 (31%) into the N-BS group. Recanalization was observed in 15 (60%) and 10 (90%) patients in the P-BS and N-BS groups, respectively (P=0.116). Hemorrhagic transformation on MRI was observed more frequently in the P-BS group than in the N-BS group (64% versus 18%; P=0.027). A good outcome (mRS, 0-1) at discharge was found in 24% of patients in the P-BS group and in 45% of patients in the N-BS group (P=0.152). A multivariate logistic regression analysis revealed that the presence of BS (odds ratio, 9.08; 95% confidence interval, 1.4-59.8; P=0.022) was independently associated with hemorrhagic transformation. BS may predict the development of hemorrhagic transformation in patients with acute stroke treated with intravenous tissue plasminogen activator.
Hitoshi Kubo, Tamaki Otani, Hideki Otsuka and Masafumi Harada : The impact of self-shielded cyclotron operation on small-animal PET/CT equipment installed nearby, on the floor just above., The Journal of Medical Investigation : JMI, Vol.61, No.1-2, 46-52, 2014.
(Summary)
The purpose of this study was to evaluate the impact of a cyclotron on small-animal PET equipment installed directly above the cyclotron. The cyclotron equipment was HM-12, which has two targets, and the PET/CT equipment was Inveon. The equipment was installed in conformity to Japanese law and regulations. Before installation of the PET/CT equipment, the radiation dose, radio waves, and static and fluctuating magnetic fields were measured at the position where it would be placed, both when the cyclotron was in use and when it was not in use. After installation of the PET/CT, natural background and emission counts were measured at the same place under the same conditions. An increase of radiation dose was observed when the target nearest the PET equipment was used. There were no distinct effects of radio waves or static and fluctuating magnetic fields. A significant increase of emission counts, approximately 300 cpm, was observed when the nearest target was used. Though radio waves and static and fluctuating magnetic fields generated by running cyclotron had no influence, a significant increase in emission count was observed. Careful attention should be paid to this influence when very low-radioactivity PET measurements are done.
(Keyword)
Animals / Cyclotrons / Equipment Failure / Japan / Magnetic Fields / Positron-Emission Tomography / Radiation Dosage / Radio Waves / Static Electricity / Tomography, X-Ray Computed
Kenji Mori, Tatsuo Mori, 郷司 彩, Hiromichi Ito, Yoshihiro Touda, Emiko Fujii, 宮崎 雅仁, Masafumi Harada and Shoji Kagami : Hemodynamic activities in children with autism while imitating emotional facial expressions: a near-infrared spectroscopy study, No to Hattatsu, Vol.46, No.4, 281-286, 2014.
(Summary)
<i><b>Objective:</b></i> To examine the hemodynamic activities in the frontal lobe, children with autistic disorder and matched controls underwent near-infrared spectroscopy (NIRS) while imitating emotional facial expressions. <i><b>Methods:</b></i> The subjects consisted of 10 boys with autistic disorder without mental retardation (9∼14 years) and 10 normally developing boys (9∼14 years). The concentrations of oxyhemoglobin (oxy-Hb) were measured with frontal probes using a 34-channel NIRS machine while the subjects imitated emotional facial expressions. <i><b>Results:</b></i> The increments in the concentration of oxy-Hb in the pars opercularis of the inferior frontal gyrus in autistic subjects were significantly lower than those in the controls. However, the concentrations of oxy-Hb in this area were significantly elevated in autistic subjects after they were trained to imitate emotional facial expressions. The increments in the concentration of oxy-Hb in this area in autistic subjects were positively correlated with the scores on a test of labeling emotional facial expressions. <i><b>Conclusions:</b></i> The pars opercularis of the inferior frontal gyrus is an important component of the mirror neuron system. The present results suggest that mirror neurons could be activated by repeated imitation in children with autistic disorder.
Youichi Otomi, Hideki Otsuka, Kaori Terazawa, Hayato Nose, Michiko Kubo, Kenji Matsuzaki, Hitoshi Ikushima, Yoshimi Bando and Masafumi Harada : Comparing the performance of visual estimation and standard uptake value of F-18 fluorodeoxyglucose positron emission tomography/computed tomography for detecting malignancy in pancreatic tumors other than invasive ductal carcinoma., The Journal of Medical Investigation : JMI, Vol.61, No.1-2, 171-179, 2014.
(Summary)
The utility of FDG PET/CT for the detection and evaluation of invasive ductal carcinoma has been widely reported, but a few studies have assessed the utility of FDG PET/CT to detect malignancy in a variety of pancreatic lesions other than invasive ductal carcinoma. To compare the diagnostic performance of visual estimation with the semi-quantitative scores of FDG PET/CT for detecting malignancy in a variety of pancreatic lesions other than invasive ductal carcinoma. Images of pathologically proven pancreatic lesions from 32 patients were retrospectively evaluated: 14 benign lesions, 7 borderline (low malignant) lesions, and 11 malignant lesions. The average scores from visual estimation by the two observers were compared to two semi-quantitative analyses of FDG uptake in the lesions, namely the maximum standardized uptake value (SUVmax) and mean standardized uptake value (SUVmean). Visual analysis value, SUVmax and SUVmean were 0.33 ± 0.21, 1.8 ± 0.7 and 1.5 ± 0.7 for the benign lesions, 0.70 ± 0.28, 5.0 ± 2.6 and 3.1±1.7 for the borderline lesions, and 0.73 ± 0.18, 4.7 ± 2.5 and 3.2 ± 1.6 for the malignant lesions, respectively. Receiver operating characteristic analysis revealed the areas under the curves for detecting non-benign (malignant or borderline) lesions through visual analysis, SUVmax, and SUVmean were 0.914, 0.954, and 0.875, respectively. For a variety of pancreatic lesions other than invasive ductal carcinoma, visual analysis and semi-quantitative analyses all showed strong diagnostic performance. However, semi-quantitative analysis with SUVmax proved to be the most effective method for detecting non-benign pancreatic lesions.
Hayato Nose, Hideki Otsuka, Youichi Otomi, K Terazawa, Shoichiro Takao, Seiji Iwamoto, Takashi Iwase, Hirotsugu Yamada, Masataka Sata and Masafumi Harada : The physiological uptake pattern of (18)F-FDG in the left ventricular myocardium of patients without heart disease., The Journal of Medical Investigation : JMI, Vol.61, No.1, 2, 53-58, 2014.
(Summary)
Purpose: The purpose of this study was to evaluate the physiological uptake pattern of 18F-FDG in the left ventricular myocardium of patients under preparation for tumor FDG-PET. Patients and Methods: We enrolled 188 patients without cardiac disease. The accumulation patterns were classified as either none, diffuse, focal or focal on diffuse. When a focal uptake was only observed on the basal wall, then the patterns were classified as having either a ring, over half or spot uptake. Results: The frequencies of the myocardial FDG uptake patterns were as follows: none, n=52 (27.7%); diffuse, n=63 (33.5%); focal on diffuse, n=40 (21.3%) and focal, n=33 (17.6%). The age, blood glucose level, weight and dose of FDG did not differ significantly for each pattern. The focal and focal on diffuse patterns were seen in 73 patients, and 65 patients had a focal uptake only on the basal wall; ring uptake in 29 patients, over half in 20 and spot uptake in 16 patients. Conclusions: The physiological myocardial uptake showed several patterns. Focal uptake was often seen in patients with cardiac disease, but it did not always indicate an abnormal finding when the accumulation was only on the basal wall.
(Keyword)
F-FDG PET / heart / physiological myocardial uptake / fasting state
Mayumi Takeuchi, Kenji Matsuzaki, Hisanori Uehara, Hiroyuki Furumoto and Masafumi Harada : Clear cell adenocarcinoma arising from clear cell adenofibroma of the ovary: value of DWI and DCE-MRI., Magnetic Resonance in Medical Sciences, Vol.12, No.4, 305-308, 2013.
(Summary)
Clear cell adenofibroma (CCAF) is a rare surface epithelial-stromal tumor of the ovary and recently considered another precursor of clear cell adenocarcinoma (CCA) other than endometrioma. We report magnetic resonance (MR) findings of a borderline CCAF that contained a small CCA focus. The tumor manifested a characteristic "black sponge" appearance. The CCA focus showed high signal intensity on diffusion-weighted imaging (DWI) and early enhancement on dynamic contrast-enhanced (DCE) MR imaging (DCE-MRI), and the CCAF components showed low signal intensity on DWI and gradually increasing contrast enhancement on DCE-MRI.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : In vivo proton MR spectroscopy in uterine abscesses., Journal of Magnetic Resonance Imaging : JMRI, Vol.38, No.4, 955-957, 2013.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Preliminary observations and clinical value of lipid peak in high-grade uterine sarcomas using in vivo proton MR spectroscopy., European Radiology, Vol.23, No.9, 2358-2363, 2013.
(Summary)
To retrospectively evaluate the clinical significance of the lipid peak in in vivo proton magnetic resonance spectroscopy (MRS) for the diagnosis of high-grade uterine sarcomas. MRS was performed in patients with 38 pathologically diagnosed uterine corpus tumours (26 leiomyomas and 12 sarcomas) at 3 T. Single-voxel MRS data were collected from a single square volume of interest that encompassed the tumours. The concentrations of lipid and total choline compounds (tCho) were classified as high, low or none. High lipid peaks were observed in all 12 sarcomas and not in benign leiomyomas except for 1 lipoleiomyoma. All 26 leiomyomas and 10 of the 12 sarcomas showed tCho peaks, whereas 2 sarcomas with massive necrosis showed no tCho peak. The presence of a high lipid peak for the diagnosis of sarcoma had a sensitivity of 100 %, specificity of 96 %, positive predictive value of 92 % and negative predictive value of 100 %. The high lipid peaks in high-grade malignant tumours may be observed in both viable and necrotic areas, and may be useful in distinguishing uterine sarcomas from benign leiomyomas. · High lipid peak on MR spectroscopy is suggestive of uterine sarcomas. · Lipid peak is observed in both viable and necrotic areas in sarcomas. · MR spectroscopy may be useful in distinguishing uterine sarcomas from benign leiomyomas.
(Keyword)
Adult / Aged / Aged, 80 and over / Choline / Female / Humans / Leiomyoma / Lipids / Magnetic Resonance Spectroscopy / Middle Aged / Necrosis / Predictive Value of Tests / Protons / Reproducibility of Results / Retrospective Studies / Sarcoma / Sensitivity and Specificity / Signal Processing, Computer-Assisted / Signal-To-Noise Ratio / Uterine Neoplasms / Uterus / Young Adult
Hitoshi Kubo, Masafumi Harada, Minoru Sakama, Tsuyoshi Matsuda and Hideki Otsuka : Preliminary observation of dynamic changes in alcohol concentration in the human brain with proton magnetic resonance spectroscopy on a 3T MR instrument, Magnetic Resonance in Medical Sciences, Vol.12, No.3, 235-240, 2013.
(Summary)
Purpose: Our purposes were to establish suitable conditions for proton magnetic resonance spectroscopy (MRS) to measure dynamic changes in alcohol concentration in the human brain, to evaluate these changes, and to compare the findings with data from analysis of breath vapor and blood samples. Materials and Methods: We evaluated 4 healthy volunteers (mean age 26.5 years; 3 males, one female) with no neurological findings. All studies were performed with 3-tesla clinical equipment using an 8-channel head coil. We applied our modified single-voxel point-resolved spectroscopy (PRESS) sequence. Continuous measurements of MRS, breath vapor, and blood samples were conducted before and after the subjects drank alcohol with a light meal. The obtained spectra were quantified by LCModel Ver. 6.1, and the accuracy of the MRS measurements was estimated using the estimated standard deviation expressed in percentage (%SD) as a criterion. Results: Alcohol peaks after drinking were clearly detected at 1.2 ppm for all durations of measurement. Good correlations between breath vapor or blood sample and MRS were found by sub-minute MRS measurement. The continuous measurement showed time-dependent changes in alcohol in the brain and various patterns that differed among subjects. Conclusions: The clinical 3T equipment enables direct evaluation of sub-minute changes in alcohol metabolism in the human brain.
Syunya Nakane, Koji Fujita, Yoshiko Shibuta, Naoko Matsui, Masafumi Harada, Ryo Urushihara, Yoshihiko Nishida, Yuishin Izumi and Ryuji Kaji : Successful treatment of stiff person syndrome with sequential use of tacrolimus, Journal of Neurology, Neurosurgery, and Psychiatry, Vol.84, No.10, 1177-1180, 2013.
(Keyword)
Aged / Autoantibodies / Brain / Dose-Response Relationship, Drug / Drug Administration Schedule / Evoked Potentials, Motor / Female / Follow-Up Studies / Glutamate Decarboxylase / Humans / Immunosuppressive Agents / Magnetic Resonance Spectroscopy / Male / Middle Aged / Motor Cortex / Neurologic Examination / Stiff-Person Syndrome / Tacrolimus / Transcranial Magnetic Stimulation / gamma-Aminobutyric Acid
高橋 英治, Hidenobu Suzuki, Yoshiki Kawata, Noboru Niki, 中野 恭幸, Junji Ueno, Masafumi Harada and 森山 紀之 : Computer Aided Diagnosis for Osteoporosis Using Chest Multi-Slice CT Images, The Transactions of the Institute of Electronics, Information and Communication Engineers D, Vol.J96-D, No.4, 892-900, 2013.
Naomi Morita, Masafumi Harada, Junichiro Satomi, Yuka Terasawa, Ryuji Kaji and Shinji Nagahiro : Frequency of emerging positive diffusion-weighted imaging in early repeat examinations at least 24 h after transient ischemic attacks, Neuroradiology, Vol.55, No.4, 399-403, 2013.
(Summary)
The relationships between diffusion lesions and risk scores for patients with a Transient ischemic attack (TIA) and the optimal timing for diffusion lesion screening have not been characterized. The purpose of our study was to evaluate the appearance of diffusion-weighted imaging (DWI) lesions during follow-up examinations of patients with TIA or minor stroke without initial DWI lesions. We identified 31 patients who did not show diffusion lesions in initial DWI. A second magnetic resonance imaging (MRI) examination was performed 24 h after the initial MRI, and the patients were divided into two groups based on the results. Demographic and clinical data, including initial National Institutes of Health Stroke Scale scores, ABCD and ABCD(2) scores, and other MRI findings were evaluated. The data were analyzed using Spearman's rank tests and unpaired t tests. Ten patients (32.3 %) showed diffusion lesions on the second DWI examination. Both risk scores were higher in these patients compared with patients with negative results on follow-up DWI (P < 0.05, unpaired t test) and correlated with the length of the TIA (R s = 0.017, P < 0.05; R s = 0.003, P < 0.01; Spearman's rank test). Our results suggest that TIA patients with high-risk scores might be underestimated if the first MRI was performed within 24 h of symptom onset.
(Keyword)
Aged / Diffusion Magnetic Resonance Imaging / Female / Humans / Incidence / Ischemic Attack, Transient / Japan / Male / Reproducibility of Results / Risk Assessment / Sensitivity and Specificity / Time Factors
Hidetaka Iwasaki, Naoki Toda, Mika Takahashi, Takahiro Azuma, Katsuhiko Nakamura, Shoichiro Takao, Masafumi Harada and Noriaki Takeda : Vestibular and cochlear neuritis in patients with Ramsay Hunt syndrome: a Gd-enhanced MRI study, Acta Oto-Laryngologica, Vol.133, No.4, 373-377, 2013.
(Summary)
It is suggested that vertigo in patients with Ramsay Hunt syndrome is mostly induced by superior vestibular neuritis consecutive to the reactivation of varicella-zoster virus (VZV) infection from the geniculate ganglion through the faciovestibular anastomosis. Refractory hearing loss in patients with Ramsay Hunt syndrome may be due to cochlear neuritis following the spread of VZV. An attempt was made to selectively identify vestibulocochlear nerves in the internal auditory canal (IAC) on gadolinium (Gd)-enhanced MRI in patients with Ramsay Hunt syndrome. Fourteen patients with Ramsay Hunt syndrome presenting with facial palsy, herpes zoster oticus, vertigo, and/or sensorineural hearing loss were scanned on 1.5 T MRI enhanced with Gd. Perpendicular section images of the IAC were reconstructed to identify the facial, superior, and inferior vestibular nerves and the cochlear nerves separately. All except one of the patients with Ramsay Hunt syndrome with vertigo showed both canal paresis on the caloric test and Gd enhancement of the superior vestibular nerve in the IAC on MRI. Among 10 patients with hearing loss, 3 patients with severe to moderate sensorineural hearing loss showed Gd enhancement of the cochlear nerve in the IAC on MRI.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Ovarian adenofibromas and cystadenofibromas: magnetic resonance imaging findings including diffusion-weighted imaging., Acta Radiologica, Vol.54, No.2, 231-236, 2013.
(Summary)
Ovarian adenofibromas (AF) and cystadenofibromas (CAF) belong to the surface epithelial-stromal tumors, and may appear as solid, or solid and cystic masses mimicking ovarian cancers. To evaluate the capability of magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) measurement for the diagnosis of ovarian AF/CAF. Magnetic resonance manifestations of 13 cases of ovarian AF/CAF were retrospectively evaluated. DWI was obtained in all 13 lesions, and mean ADC values in 11 lesions were compared with those in solid portions of 27 ovarian cancers. Results Neither case with AF/CAF revealed high signal intensity on DWI, whereas all ovarian cancers showed high signal intensity on DWI. The ADC values in the solid portions of AF/CAF were significantly higher than those of ovarian cancers (P < 0.001). A cut-off value of 1.20 × 10(-3) mm(2)/s for AF/CAF had a sensitivity of 82%, specificity of 93%, positive predictive value of 82%, and negative predictive value of 93%. DWI with ADC measurement may be helpful in differentiating AF/CAF from ovarian cancers.
(Keyword)
Adenofibroma / Adult / Aged / Cystadenofibroma / Diffusion Magnetic Resonance Imaging / Female / Humans / Magnetic Resonance Imaging / Middle Aged / Ovarian Neoplasms / Predictive Value of Tests / Sensitivity and Specificity
Koji Fujita, W Sakai, Masafumi Harada, Mika Sakaki, Hideo Mure, Shinji Nagahiro, Yuishin Izumi and Ryuji Kaji : Basal ganglia hyperintensity on T1-weighted imaging of a patient with central nervous system metastasis producing carcinoembryonic antigens, Internal Medicine, Vol.52, No.3, 381-383, 2013.
(Summary)
We herein report unusual basal ganglia hyperintense lesions on noncontrast T1-weighted magnetic resonance imaging in a patient with central nervous system metastasis from lung adenocarcinoma that was treated with gefitinib. T2*-weighted magnetic resonance imaging showed no hypointense lesions, thereby excluding the possibility of calcification or haemorrhage. A stereotactic brain biopsy of the left basal ganglia lesions revealed atypical cells, some of which formed a glandular lumen with a micropapillary pattern. These cells were immunopositive for markers of lung adenocarcinoma, thereby confirming the diagnosis of metastasis. We speculate that proteins, including carcinoembryonic antigens from the adenocarcinoma cells in the basal ganglia, may have contributed to the hyperintensity observed on noncontrast T1-weighted magnetic resonance imaging.
Kenji Mori, Yoshihiro Touda, Hiromichi Ito, T Mori, A Goji, Emiko Fujii, M Miyazaki, Masafumi Harada and Shoji Kagami : A proton magnetic resonance spectroscopic study in autism spectrum disorders: amygdala and orbito-frontal cortex., Brain & Development, Vol.35, No.2, 139-145, 2013.
(Summary)
We previously reported neural dysfunction in the anterior cingulate cortex and dorsolateral prefrontal cortex in autistic patients using proton magnetic resonance spectroscopy ((1)H-MRS). In this investigation, we measured chemical metabolites in the left amygdala and the bilateral orbito-frontal cortex (OFC), which are the main components of the social brain. We also examined the association between these metabolic findings and social abilities in subjects with autism. The study group included 77 autistic patients (3-6years old; mean age 4.1; 57 boys and 20 girls). The control subjects were 31 children (3-6years old; mean age 4.0; 23 boys and 8 girls). Conventional proton MR spectra were obtained using the STEAM sequence with parameters of TR=5 sec and TE=15 msec by a 1.5-tesla clinical MRI system. We analyzed the concentrations of N-acetylaspartate (NAA), creatine/phosphocreatine (Cr), and choline-containing compounds (Cho) using LCModel (Ver. 6.1). The concentrations of NAA in the left amygdala and the bilateral OFC in autistic patients were significantly decreased compared to those in the control group. In the autistic patients, the NAA concentrations in these regions correlated with their social quotient. These findings suggest the presence of neuronal dysfunction in the amygdala and OFC in autism. Dysfunction in the amygdala and OFC may contribute to the pathogenesis of autism.
(Keyword)
Amygdala / Aspartic Acid / Child / Child Development Disorders, Pervasive / Child, Preschool / Choline / Creatinine / Diagnostic and Statistical Manual of Mental Disorders / Female / Functional Laterality / Humans / Intelligence Tests / Magnetic Resonance Imaging / Magnetic Resonance Spectroscopy / Male / Phosphocreatine / Prefrontal Cortex / Protons
Hayato Nose, Hideki Otsuka, Youichi Otomi, Kaori Terazawa, Shoichiro Takao, Seiji Iwamoto and Masafumi Harada : Correlations between F-18 FDG PET/CT and pathological findings in soft tissue lesions., The Journal of Medical Investigation : JMI, Vol.60, No.3-4, 184-190, 2013.
(Summary)
Objective: To evaluate the correlations between F-18 FDG uptake imaged with PET/CT and pathological findings in soft tissue lesions. Methods: Fifty-four soft tissue lesions in 47 patients were evaluated. The correlations between the degree of FDG uptake, pathological type and grade, and MRI signal intensity and/or enhancement pattern were evaluated. Tumor FDG uptake was quantified by the maximum standardized uptake value (SUVmax). Results: Thirty-one lesions were malignant and twenty-three lesions were benign. The difference between SUVmax in the malignant and benign groups was statistically significant (p<0.001). Malignant myxoid lesions and well differentiated liposarcoma showed low FDG uptake. Benign neurogenic lesions showed low FDG uptake while malignant neurogenic tumors showed high FDG uptake, and the difference between SUVmax in the benign and malignant lesions was statistically significant (p<0.001). In a neurofibromatosis type-1 patient who had multiple neurogenic tumors, FDG-PET/CT could distinguish malignant peripheral nerve sheath tumors from other benign lesions with similar MRI findings. Conclusions: FDG-PET/CT is useful for differentiating malignant from benign soft tissue lesions, but malignant soft tissue lesions may show various patterns on FDG-PET, and MRI may be helpful for a differential diagnosis. J. Med. Invest. 60: 184-190, August, 2013.
Ayumi Nose, Hideki Otsuka, Hayato Nose, Yoichi Otomi, Kaori Terazawa and Masafumi Harada : Visual and semi-quantitative assessment of brain tumors using (201)Tl-SPECT., The Journal of Medical Investigation : JMI, Vol.60, No.1-2, 121-126, 2013.
(Summary)
To evaluate the usefulness of (201)Tl-SPECT in differentiating benign from malignant brain tumors. Eighty-eight patients (44 males and 44 females) with 58 high-grade (WHO grade III-IV) and 30 low-grade (WHO grade I-II) tumors were evaluated with (201)Tl-SPECT. (1) Visual assessment was performed by board-certificated radiologists using (201)Tl-SPECT. Tumors were classified in two groups (Tl-positive and Tl-negative) and scored using the five grade evaluation system. Receiver operating characteristic (ROC) analysis was performed in the Tl-positive group. (2) Semi-quantitative assessment involved measurement of early and delayed (201)Tl uptake, and the retention index (RI) was applied as follows: RI=delayed uptake ratio/early uptake ratio. Three combinations of RI using mean and maximum values of the region of interest were calculated. (1) Seventy-four Tl-positive and 14 Tl-negative tumors. The area under the ROC curve (AUC) estimated by three radiologists exceeded a value of 0.7. The value was greater when estimated by the more experienced radiologist. (2) In all RIs, the difference of RI between high-grade tumors and low-grade tumors was statistically significant. A visual and semi-quantitative assessment using (201)Tl-SPECT was found to be useful for differentiating benign from malignant brain tumors.
Yoichi Otomi, Hideki Otsuka, Kaori Terazawa, Hayato Nose, Michiko Kubo, Kazuhide Yoneda, Kaoru Kitsukawa and Masafumi Harada : (18)F-2-fluoro-2-deoxyglucose uptake in or adjacent to blood vessel walls., The Journal of Medical Investigation : JMI, Vol.60, No.1-2, 15-20, 2013.
(Summary)
Incidental (18)F-2-fluoro-2-deoxyglucose (FDG) uptake in blood vessel walls is sometimes demonstrated during routine oncologic imaging with positron emission tomography/computed tomography (PET/CT). FDG uptake in vessel walls can also be seen under some non-physiological conditions such as vasculitis and arteriosclerosis. Radiologists need to be aware of the diseases which can exhibit FDG uptake in the vessel wall for proper interpretation.
Munkhbaatar Dagvasumberel, Michio Shimabukuro, Nishiuchi Takeshi, Junji Ueno, Shoichiro Takao, Daiju Fukuda, Hirata Yoichiro, Hirotsugu Kurobe, Takeshi Soeki, Takashi Iwase, Kenya Kusunose, Toshiyuki Niki, Koji Yamaguchi, Yoshio Taketani, Shusuke Yagi, Tomita Noriko, Hirotsugu Yamada, Tetsuzo Wakatsuki, Masafumi Harada, Tetsuya Kitagawa and Masataka Sata : Gender disparities in the association between epicardial adipose tissue volume and coronary atherosclerosis: A 3-dimensional cardiac computed tomography imaging study in Japanese subjects., Cardiovascular Diabetology, Vol.11, No.1, 106, 2012.
(Summary)
Growing evidence suggests that epicardial adipose tissue (EAT) may contribute to the development of coronary artery disease (CAD). In this study, we explored gender disparities in EAT volume (EATV) and its impact on coronary atherosclerosis. The study population consisted of 90 consecutive subjects (age: 63 ± 12 years; men: 47, women: 43) who underwent 256-slice multi-detector computed tomography (MDCT) coronary angiography. EATV was measured as the sum of cross-sectional epicardial fat area on CT images, from the lower surface of the left pulmonary artery origin to the apex. Subjects were segregated into the CAD group (coronary luminal narrowing > 50%) and non-CAD group. EATV/body surface area (BSA) was higher among men in the CAD group than in the non-CAD group (62 ± 13 vs. 33 ± 10 cm3/m2, p < 0.0001), but did not differ significantly among women in the 2 groups (49 ± 18 vs. 42 ± 9 cm3/m2, not significant). Multivariate logistic analysis showed that EATV/BSA was the single predictor for >50% coronary luminal narrowing in men (p < 0.0001). Predictors excluded were age, body mass index, hypertension, diabetes mellitus, and hyperlipidemia. Increased EATV is strongly associated with coronary atherosclerosis in men.
(Keyword)
Adipose Tissue / Age Factors / Aged / Asian Continental Ancestry Group / Body Surface Area / Chi-Square Distribution / Coronary Angiography / Coronary Artery Disease / Coronary Stenosis / Female / Health Status Disparities / Humans / Japan / Logistic Models / Male / Middle Aged / Multidetector Computed Tomography / Multivariate Analysis / Pericardium / Predictive Value of Tests / Risk Assessment / Risk Factors / Severity of Illness Index / Sex Factors
Tatsuo Mori, Kenji Mori, Emiko Fujii, Yoshihiro Touda, Masahito Miyazaki, Masafumi Harada, Toshiaki Hashimoto and Shoji Kagami : Evaluation of the GABAergic nervous system in autistic brain: (123)I-iomazenil SPECT study., Brain & Development, Vol.34, No.8, 648-654, 2012.
(Summary)
To evaluate the GABA(A) receptor in the autistic brain, we performed (123)I-IMZ SPECT in patients with ASD. We compared (123)I-IMZ SPECT abnormalities in patients who showed intellectual disturbance or focal epileptic discharge on EEG to those in patients without such findings. The subjects consisted of 24 patients with ASD (mean age, 7.3±3.5 years), including 9 with autistic disorder (mean age, 7.0±3.7 years) and 15 with Asperger's disorder (mean age, 7.5±3.2 years). We used 10 non-symptomatic partial epilepsy patients (mean age, 7.8±3.6 years) without intellectual delay as a control group. For an objective evaluation of the (123)I-IMZ SPECT results, we performed an SEE (Stereotactic Extraction Estimation) analysis to describe the decrease in accumulation in each brain lobule numerically. In the comparison of the ASD group and the control group, there was a dramatic decrease in the accumulation of (123)I-IMZ in the superior and medial frontal cortex. In the group with intellectual impairment and focal epileptic discharge on EEG, the decrease in accumulation in the superior and medial frontal cortex was greater than that in the group without these findings. The present results suggest that disturbance of the GABAergic nervous system may contribute to the pathophysiology and aggravation of ASD, since the accumulation of (123)I-IMZ was decreased in the superior and medial frontal cortex, which is considered to be associated with inference of the thoughts, feelings, and intentions of others (Theory of Mind).
Ryosuke Miyamoto, Satoshi Goto, Wataru Sako, Ai Miyashiro, Isabelle Kim, Fabienne Escande, Masafumi Harada, Ryoma Morigaki, Koutaro Asanuma, Yoshifumi Mizobuchi, Shinji Nagahiro, Yuishin Izumi and Ryuji Kaji : Generalized dystonia in a patient with a novel mutation in the GLUD1 gene, Movement Disorders, Vol.27, No.9, 1198-1199, 2012.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Preliminary observations and diagnostic value of lipid peak in ovarian thecomas/fibrothecomas using in vivo proton MR spectroscopy at 3T., Journal of Magnetic Resonance Imaging : JMRI, Vol.36, No.4, 907-911, 2012.
(Summary)
To retrospectively evaluate the significance of lipid peak in in vivo proton magnetic resonance (MR) spectroscopy for the diagnosis of ovarian thecomas/fibrothecomas in patients with solid gynecologic tumors exhibiting totally or partially low signal intensity on T2-weighted images. MR spectroscopy was performed in patients with pathologically diagnosed gynecologic tumors at 3T MRI. Single-voxel MR spectroscopy data were collected from a single square volume of interest that encompassed the gynecologic masses. The lipid concentration level was classified into three classes (high; low; none). A total of 20 gynecologic tumors in 20 patients were evaluated in this study. High lipid peak was observed in all seven thecomas/fibrothecomas, whereas low lipid peak was observed in only one fibroma in 13 nonthecomatous tumors (six benign ovarian tumors and seven subserosal uterine leiomyomas). The presence of lipid peak for the diagnosis of thecomas/fibrothecomas had a sensitivity of 100%, specificity of 92%, positive predictive value of 88%, and negative predictive value of 100%. The high lipid peak reflecting abundant intracellular lipid contents is considered a specific metabolite concentration for thecomas/fibrothecomas. Demonstration of high lipid peak may contribute to the diagnosis of thecomas/fibrothecomas in distinguishing from other benign ovarian fibrous tumors or subserosal uterine leiomyomas.
Toru Utsunomiya, Mitsuo Shimada, Jun Hanaoka, Mami Kanamoto, Tetsuya Ikemoto, Yuji Morine, Satoru Imura and Masafumi Harada : Possible utility of MRI using Gd-EOB-DTPA for estimating liver functional reserve, Journal of Gastroenterology, Vol.47, No.4, 470-476, 2012.
(Summary)
Preoperative estimation of the liver functional reserve is important in liver surgery. We evaluated the role of dynamic magnetic resonance (MR) imaging with gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA), i.e., EOB-MRI, for determining liver functional reserve. Fifty patients who underwent EOB-MRI to examine their liver tumors were included in this study. We first performed a pixel-by-pixel comparison of registered MR images and activity images with Tc-99m galactosyl human serum albumin (GSA) on each slice, and the correlation coefficient was calculated for 8 patients. We also determined the correlation coefficient between the relative signal intensity (SI) values of EOB-MRI and preoperative liver function, such as the GSA, indocyanine green dye retention at 15 min (ICGR15), and prothrombin time. The mean of the correlation coefficients for 512 × 512 matrices between the EOB-MRI and the GSA was 0.83 ± 0.05 (ranging from 0.73 to 0.87). The correlation coefficient between the relative SI of the EOB-MRI and the receptor index (LHL15) of GSA was 0.56 (P < 0.01). Better correlation coefficients were observed between the relative SI and the liver function test, including ICGR15 (r = -0.67, P < 0.01) and prothrombin time (r = 0.59, P < 0.01). In a patient with hilar cholangiocarcinoma whose right hepatic duct was obstructed, the relative SI in the right lobe (2.4 ± 0.3) was significantly lower than that in the left lobe (3.1 ± 0.1). EOB-MRI represents a practical and reliable imaging technique that may be used to estimate regional liver functional reserve in the clinical setting.
(Keyword)
Adult / Aged / Aged, 80 and over / Contrast Media / Female / Gadolinium DTPA / Humans / Liver / Liver Function Tests / magnetic resonance imaging / Male / Middle Aged
Seiji Iwamoto, Shoichiro Takao, Hayato Nose, Yoichi Otomi, Mitsuhiko Takahashi, Toshihiko Nishisho, Junji Ueno, Natsuo Yasui and Masafumi Harada : Usefulness of transcatheter arterial embolization prior to excision of hypervascular musculoskeletal tumors., The Journal of Medical Investigation : JMI, Vol.59, No.3-4, 284-288, 2012.
(Summary)
The objective of this study was to evaluate the usefulness of transcatheter arterial embolization prior to surgical excision of musculoskeletal tumors. We reviewed the records of nine patients (3 females and 6 males) who received arterial embolization prior to excision of musculoskeletal tumors in our hospital from December 2009 to April 2010. We evaluated tumor region, size, histopathology, feeding artery, embolic material, and blood loss during surgery. We compared the actual amount of intraoperative bleeding with arterial embolization to estimated amounts of bleeding without embolization predicted by three orthopedic surgeons. Arterial embolization was performed on the same day or within 5 days before surgery. Operations were performed as planned in all patients without serious complications. The amount of intraoperative bleeding was 35-4200 mL and there was significantly less bleeding with arterial embolization compared with the estimated amounts (p<0.01). Our results show that arterial embolization prior to resection of hypervascular musculoskeletal tumors reduces the amount of bleeding during surgery and contributes to patient safety.
Tatsuo Mori, Kenji Mori, Emiko Fujii, Yoshihiro Touda, Masahito Miyazaki, Masafumi Harada and Shoji Kagami : Neuroradiological and neurofunctional examinations for patients with 22q11.2 deletion., Neuropediatrics, Vol.42, No.6, 215-221, 2011.
(Summary)
Since the neuroradiological features of patients with 22q11.2 deletion syndrome are not well-understood, examinations using functional imaging were performed in this study. Brain magnetic resonance imaging (MRI) and 1H-magnetic resonance spectroscopy (MRS) were performed using a clinical 3-Tesla MR imager in 4 patients with 22q11.2 deletion syndrome (2 boys and 2 girls; aged 2-6 years.) and 20 age- and sex-matched healthy control subjects. Furthermore, interictal 123I-iomazenil (IMZ) single photon emission computed tomography (SPECT) was examined in 2 of the 4 patients. Among the 4 patients with 22q11.2 deletion syndrome, 2 patients showed polymicrogyria and 1 patient showed agyria. Those patients with brain malformations also showed abnormal brain artery patterns and decreased accumulation of IMZ in 123I-IMZ SPECT. Although all 4 patients showed epileptic discharges in their electroencephalograms (EEG), one patient with polymicrogyria had no seizure episodes. Decreases in γ-aminobutyric acid (GABA) corresponding to the areas of polymicrogyria and/or epileptic discharges in EEG were shown in all patients except for the patient with agyria. Although consistent evidence was not seen in patients with 22q11.2 deletion syndrome in this study, brain malformations and disturbances of the GABAergic nervous system would be underlying mechanisms of the neurodevelopmental abnormalities in this syndrome.
(Keyword)
Case-Control Studies / children / Child, Preschool / DiGeorge Syndrome / Electroencephalography / Epilepsy / Female / Flumazenil / Humans / hydrogen / magnetic resonance imaging / nuclear magnetic resonance spectroscopy / Male / Malformations of Cortical Development / Tomography, Emission-Computed, Single-Photon / gamma-Aminobutyric Acid
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Preliminary observations and clinical value of N-acetyl resonances in ovarian tumours using in-vivo proton MR spectroscopy at 3T., European Radiology, Vol.21, No.12, 2640-2646, 2011.
(Summary)
To retrospectively evaluate the clinical significance of N-acetyl resonances at 2 ppm in in-vivo proton magnetic resonance (MR) spectroscopy for distinguishing mucinous and non-mucinous tumours in patients with ovarian masses. MR spectroscopy was performed in patients with pathologically diagnosed ovarian tumours at 3T-MR imaging. Single-voxel MR spectroscopy data were collected from a single square volume of interest that encompassed the ovarian masses. The metabolite resonance peak areas at 2 ppm were quantified relative to unsuppressed water using a software package (LCModel). A total of 32 ovarian lesions in 32 patients were evaluated in this study. High metabolite peak at 2 ppm was observed in all nine mucinous tumours (9.71 +/- 7.46 mM), whereas low peak was observed in 14 of 23 non-mucinous tumours (3.12 +/- 1.42 mM) (p < 0.001). Using a cut off value of 4.45 mM for mucinous tumours had a sensitivity of 89%, specificity of 86%, PPV of 80%, and NPV of 92%. Proton MR spectroscopy with quantitative evaluation of the metabolite at 2 ppm concentration, which may suggest the presence of mucinous material containing N-acetyl mucinous compounds, can provide helpful information in distinguishing mucinous and non-mucinous ovarian tumours. Key Points MR spectroscopy helps distinguish mucinous from non-mucinous ovarian tumours. High N-acetyl resonance at 2 ppm is observed in ovarian mucinous tumours. Thus MR spectroscopy could improve management of these patients.
Masafumi Harada, Hitoshi Kubo, Ayumi Nose, Hiromu Nishitani and Tsuyoshi Matsuda : Measurement of variation in the human cerebral GABA level by in vivo MEGA-editing proton MR spectroscopy using a clinical 3 T instrument and its dependence on brain region and the female menstrual cycle., Human Brain Mapping, Vol.32, No.5, 828-833, 2011.
(Summary)
The objectives of this study were to examine the reproducibility of the MEGA-editing J-difference technique and to determine the normal variation in the γ-aminobutyric acid (GABA) level depending on the cerebral region and its fluctuation according to the menstrual cycle as baseline data for clinical application. The participants consisted of 15 normal adult volunteers (eight men and seven women), and all measurements were repeated twice in all participants. The MEGA-editing pulses were incorporated into point-resolved spectroscopy on a 3 T instrument to obtain the J-difference editing spectra from a voxel located in the lentiform nuclei (LN), left frontal lobe (FL), and anterior cingulate cortex (AC). The GABA levels in the gray matter (GM) were compensated by the fraction ratios of the gray and white matters and cerebrospinal fluid in the measurement volume. The extent of the variation in GABA was almost the same as that observed in the major metabolites, and its reproducibility was also maintained (intraclass correlation coefficient > 0.7). GABA level was highest in LN and lowest in AC. A difference in the GABA level between the follicular and luteal phases of the menstrual cycle was found in both LN and FL, but not in AC. This technique showed the differences in the GABA levels in the GM and the region-specific decrease in the GABA levels during the women's luteal phase.
(Keyword)
Brain Chemistry / Brain Mapping / Cerebral Cortex / Female / Humans / Image Interpretation, Computer-Assisted / Magnetic Resonance Spectroscopy / Male / Menstrual Cycle / Protons / Reproducibility of Results / Young Adult / gamma-Aminobutyric Acid
Masafumi Harada, Masako M. Taki, Ayumi Nose, Hitoshi Kubo, Kenji Mori, Hiromu Nishitani and Tsuyoshi Matsuda : Non-invasive evaluation of the GABAergic/glutamatergic system in autistic patients observed by MEGA-editing proton MR spectroscopy using a clinical 3 tesla instrument., Journal of Autism and Developmental Disorders, Vol.41, No.4, 447-454, 2011.
(Summary)
Amino acids related to neurotransmitters and the GABAergic/glutamatergic system were measured using a 3 T-MRI instrument in 12 patients with autism and 10 normal controls. All measurements were performed in the frontal lobe (FL) and lenticular nuclei (LN) using a conventional sequence for n-acetyl aspartate (NAA) and glutamate (Glu), and the MEGA-editing method for GABA. The GABA level and [GABA]/[NAA] ratio were significantly lower (p < 0.01) in the FL, but not the LN, in patients with autism compared to normal controls. The [GABA]/[Glu] ratio in the FL was also significantly lower (p < 0.05) in the patients than in the normal controls, thus suggesting a possible abnormality in the regulation between GABA and Glu.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Differentiation of benign and malignant uterine corpus tumors by using proton MR spectroscopy at 3T: preliminary study., European Radiology, Vol.21, No.4, 850-856, 2011.
(Summary)
To retrospectively evaluate the diagnostic ability of magnetic resonance (MR) spectroscopy for distinguishing benign and malignant lesions in patients with uterine corpus tumours at MR imaging. Pelvic MR spectroscopy was performed in patients with pathologically diagnosed benign and malignant uterine corpus tumours at 3T-MR imaging. Single-voxel MR spectroscopy data were collected from a single square volume of interest that encompassed the uterine corpus lesion. The total choline compounds (tCho) resonance peak areas were quantified relative to unsuppressed water using a software package. Patients who fulfilled the criteria for estimates of acceptable reliability were included. A total of 32 patients (age range, 24-76 years) with 32 lesions were evaluated in this study. The median lesion size at MR imaging was 50 mm (range, 19-218 mm). A tCho peak was present in all 32 lesions including 14 malignant lesions (9.21 ± 2.21 mM), and 18 benign lesions (4.59 ± 2.22 mM) (p < 0.0001). Using a cut-off value of 7.00 mM for malignant lesions had a sensitivity of 93%, specificity of 83%, PPV of 81% and NPV of 94%. Proton MR spectroscopy with quantitative evaluation of tCho concentration can provide helpful information in distinguishing benign and malignant uterine corpus tumours.
Hirokazu Iwasaki, Hitoshi Kubo, Masafumi Harada, Hiromu Nishitani and Ohashi Yasushi : Temporomandibular joint and 3.0T pseudodynamic magnetic resonance imaging. Part 2: evaluation of articular disc obscurity., Dento Maxillo Facial Radiology, Vol.39, No.8, 486-493, 2010.
(Summary)
This study examined the relationship between temporomandibular joint (TMJ) dysfunctions and obscurity grades of interpreted anterior and posterior borders of the articular disc (Da and Dp, respectively) by 3.0 T pseudodynamic MRI. Da and Dp were classified into seven obscurity grades, and the Dp contour was classified into three types. The grades, types and TMJ function were compared by 3.0 T pseudodynamic MRI. Unobscured Da images at condylar positions posterior to the articular eminence were associated with normal TMJ function (P = 0.046 < 0.05). Unobscured Dp images at condylar positions anterior to the articular eminence were associated with normal TMJ function (P = 0.033 < 0.05). In addition, unobscured Dp images following flap insertion were associated with normal TMJ function (P = 0.043 < 0.05). There was no statistical relationship between Dp contour types and TMJ movement, but any change observed in the Dp contour during mouth opening was associated with abnormal TMJ function (P = 0.040 < 0.05). Grading of Da and Dp obscurity based on how well the areas were defined in the images, identifying the condylar positions in relation to the glenoid fossa and articular eminences, and observing the changes in Dp contour types were useful for diagnosing TMJ abnormalities.
Hirokazu Iwasaki, Hitoshi Kubo, Masafumi Harada and Hiromu Nishitani : Temporomandibular joint and 3.0T pseudodynamic magnetic resonance imaging. Part 1: evaluation of condylar and disc dysfunction., Dento Maxillo Facial Radiology, Vol.39, No.8, 475-485, 2010.
(Summary)
This study describes an improved method for examining and diagnosing temporomandibular joint (TMJ) dynamics by 3.0 T pseudodynamic MRI. Clinical observation and conventional static MRI of volunteers (one without and eight with TMJ arthrosis) were followed by 3.0 T pseudodynamic MRI in positions ranging from the mouth closed to mouth fully opened. Condylar head (Cd), articular disc anterior border (Da) and articular disc posterior border (Dp) were digitized on sagittal images to determine trajectory and velocity patterns. Patients were divided into three groups based on the presence or absence of dysfunction: Group 1, no dysfunction on the right or left side of the TMJ; Group 2, dysfunction on the right or left side of the TMJ; and Group 3, dysfunction on both the right and left sides of the TMJs. In 75% of patients (12 of 16 joints), pseudodynamic TMJ analysis was useful for determining a functional abnormality. Using a points system based on three trajectory and seven velocity patterns, discs with adhesion and perforation had significantly fewer points than discs with anterior displacement (with and without reduction) and discs with no abnormality (P = 0.019 < 0.05). Trajectory and velocity patterns based on 3.0 T pseudodynamic MRI identified the affected side and determined the extent of morbidity in the Cd as well as the Da and Dp. The typical abnormal movement pattern of discs with anterior displacement (with and without reduction) and pathological structural changes of the articular disc (such as adhesion and perforation) could be identified.
(Keyword)
temporomandibular joint / nuclear magnetic resonance / Kinematics / biomechanics
Masafumi Harada, Naomi Morita, Masaaki Uno, Junichiro Satomi, Yuishin Izumi, Koutaro Asanuma, Hiromu Nishitani, Ryuji Kaji and Shinji Nagahiro : Incidence and clinical correlation of intracranial hemorrhages observed by 3-tesla gradient echo T2*-weighted images following intravenous thrombolysis with recombinant tissue plasminogen activator, Cerebrovascular Diseases, Vol.29, No.6, 571-575, 2010.
(Summary)
The purpose of this study was to determine the incidence and clinical correlation of intracranial hemorrhages (ICHs) detected by 3-tesla gradient echo T(2)*-weighted images after intravenous recombinant tissue plasminogen activator (rt-PA) administration. We included 43 consecutive patients with anterior-circulation ischemia who underwent MRI studies before and after thrombolysis. Each hemorrhage was classified as a hemorrhagic infarction (HI) or parenchymal hemorrhage (PH) according to the European Cooperative Acute Stroke Study definition. The clinical outcome was defined as an improvement (> or =4-point reduction) or deterioration (> or =4-point increase) based on a comparison between the initial and the 30-day NIHSS scores. The incidence of ICHs was 58%, and the HI rate was 52%; both were higher than the rates reported in the literature. Most of the patients with HI improved clinically, and these patients had second MRAs that showed recanalization. None of the patients with PH demonstrated improvement. Three-tesla MRI may reveal a higher frequency of HI type hemorrhages than lower-field MRIs, and HI may be a predictor of good recovery by reflecting the presence of recanalization. The rate of PH in our study was low compared to other studies, probably due to the lower dosage of rt-PA.
Shinya Tayoshi, Masahito Nakataki, Satsuki Sumitani, Kyoko Taniguchi, Sumiko Tayoshi, Shusuke Numata, Junichi Iga, Shu-ichi Ueno, Masafumi Harada and Tetsuro Ohmori : GABA concentration in schizophrenia patients and the effects of antipsychotic medication: a proton magnetic resonance spectroscopy study., Schizophrenia Research, Vol.117, No.1, 83-91, 2010.
(Summary)
Gamma-amino butyric acid (GABA) is thought to play a role in the pathophysiology of schizophrenia. High magnetic field proton magnetic resonance spectroscopy ((1)H-MRS) provides a reliable measurement of GABA in specific regions of the brain. This study measured GABA concentration in the anterior cingulate cortex (ACC) and in the left basal ganglia (ltBG) in 38 patients with chronic schizophrenia and 29 healthy control subjects. There was no significant difference in GABA concentration between the schizophrenia patients and the healthy controls in either the ACC (1.36+/-0.45 mmol/l in schizophrenia patients and 1.52+/-0.54 mmol/l in control subjects) or the ltBG (1.13+/-0.26 mmol/l in schizophrenia patients and 1.18+/-0.20 mmol/l in control subjects). Among the right handed schizophrenia patients, the GABA concentration in the ltBG was significantly higher in patients taking typical antipsychotics (1.25+/-0.24 mmol/l) than in those taking atypical antipsychotics (1.03+/-0.24 mmol/l, p=0.026). In the ACC, the GABA concentration was negatively correlated with the dose of the antipsychotics (rs=-0.347, p=0.035). In the ltBG, the GABA concentration was positively correlated with the dose of the anticholinergics (rs=0.403, p=0.015). To the best of our knowledge, this is the first study to have directly measured GABA concentrations in schizophrenia patients using (1)H-MRS. Our results suggest that there are no differences in GABA concentrations in the ACC or the ltBG of schizophrenia patients compared to healthy controls. Antipsychotic medication may cause changes in GABA concentration, and atypical and typical antipsychotics may have differing effects. It is possible that medication effects conceal inherent differences in GABA concentrations between schizophrenia patients and healthy controls.
Masafumi Harada, Hitoshi Kubo, Takamasa Abe, Hiroshi Maezawa and Hideki Otsuka : Selection of endogenous 13C substrates for observation of intracellilar metabolism using the dynamic nuclear polarization technique, Japanese Journal of Radiology, Vol.28, No.2, 173-179, 2010.
(Summary)
The aim of this study was to select a suitable substrate candidate for dynamic nuclear polarization (DNP) studies and demonstrate its utility for evaluating intracellular metabolism. Hyperpolarized substances included 1-(13)C-pyruvate (Pyr), 1-(13)C-glucose (Glc), and 1-(13)C-acetate. A DNP polarizer and a 600-MHz vertical small-bore scanner were used for (13)C-MR spectroscopic measurements. After polarization for 1 h, the dissolved solution was injected via a capillary line into the nuclear magnetic resonance tube in the scanner. The sequential spectra of the hyperpolarized (13)C-labeled substrates were acquired in durations of more than 120 s, and a thermal spectrum was obtained more than 1 h thereafter. FM3A cancer cells of mammary tumors were cultured for intracellular detection of the hyperpolarized (13)C-substances. The greatest sensitivity was found using Pyr with the longest T1 decay (51.5 s); and remarkably, the least sensitivity was observed using Glc with a signal decay of less than 2 s. An effective increase in sensitivity was shown using the other substances. The hyperpolarized intracellular study using (13)C-Pyr showed distinct elevation of lactate levels. The DNP technique is useful for evaluating intracellular metabolism. However, Glc is not suitable for use with the DNP technique.
Kaori Terazawa, Hideki Otsuka, Youichi Otomi, Naomi Morita, Shoichiro Takao, Seiji Iwamoto, Kyosuke Osaki, Masafumi Harada and Hiromu Nishitani : How to manage RI venography in pre-orthopedic surgery patients, Annals of Nuclear Medicine, Vol.24, No.2, 107-113, 2010.
(Summary)
The preoperative evaluation of venous thromboembolism (VTE) is important to avoid complications, because VTE is often induced by orthopedic surgery. We focused on radioisotope venography (RIV) using 99mTc-macroaggregated human serum albumin, examining orthopedic patients. We conducted 34 examinations in 33 patients who were referred for RIV and lung perfusion scintigraphy for the pre-orthopedic operative evaluation of VTE. Two board-certified (one nuclear medicine board-certified) radiologists interpreted the images based on the following: (1) flow defect of the lower extremities; (2) interruption of flow; (3) irregular or asymmetric filling of the deep vein (low flow); (4) presence of collateral vessels; and (5) abnormal RI retention on delayed-phase images. Scoring was based on a 5-point scale, and more than 2 points was considered VTE positive. Abnormal findings were noted in 27 of the 34 examinations performed in the 33 patients and normal findings in the other 7 examinations. According to the RI score, 21 patients were classified into the VTE-positive group and 12 into the VTE-negative group. Surgery was canceled because of advanced age and respiratory dysfunction in 2 of the 21 patients in the VTE-positive group. Of the 19 patients who underwent surgery, an IVH filter was placed before surgery in 2 and anticoagulant treatment with heparin and warfarin was initiated on the day of surgery in 12 to prevent postoperative VTE, and only one of the patients receiving anticoagulant treatment developed PTE after surgery. Surgery was canceled due to advanced age and at patient's request in 2 of 12 patients in the VTE-negative group. Anticoagulant treatment with heparin/ warfarin was performed to prevent postoperative VTE in only 3 patients: one with a past medical history of pulmonary infarction, one with atrial fibrillation, and one suspected of having antiphospholipid antibody syndrome. No patient in the VTE-negative group developed VTE after surgery. The preoperative identification of patients with VTE by RIV might be useful for perioperative management and the evaluation of preventive measures against postoperative VTE.
(Keyword)
Adult / Aged / Aged, 80 and over / Female / Humans / Male / Middle Aged / Organotechnetium Compounds / Orthopedics / Phlebography / Radioisotopes / Serum Albumin / Venous Thromboembolism
Yoshiteru Tada, Masaaki Uno, Shunji Matsubara, Atsuhiko Suzue, Kenji Shimada, Naomi Morita, Masafumi Harada and Shinji Nagahiro : Reversibility of ischemic findings on 3-T T2*-weighted imaging after emergency superficial temporal artery-middle cerebral artery anastomosis in patients with progressive ischemic stroke., Neurologia Medico-Chirurgica, Vol.50, No.11, 1006-1011, 2010.
(Summary)
Vascular ischemic signs, i.e. multiple hypointense vessels in the ischemic territory, were identified by gradient echo-type 3-T T(2)*-weighted magnetic resonance (MR) imaging in 3 patients with acute ischemia due to major vessel occlusion. Emergency superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis was performed in 2 patients with progressive stroke caused by bleeding-type moyamoya disease or severe MCA stenosis. Both patients were initially treated conservatively, but their neurological signs deteriorated. 3-T T(2)*-weighted MR imaging detected funicular low signals in both patients indicating enhancement of cortical vessels or medullary veins. The area of the vascular ischemic signs was almost the same or smaller than the hypoperfusion area on perfusion-weighted MR imaging or single-photon emission computed tomography. Postoperatively, the vascular ischemic signs disappeared in both patients, suggesting a relationship with severe ischemia due to high-risk misery perfusion. Their postoperative course was uneventful, and MR imaging revealed no new cerebral ischemic lesions or cerebral hyperperfusion. The patient without surgery developed cerebral infarction in the area of the vascular ischemic signs. Vascular ischemic signs detected by 3-T T(2)*-weighted MR imaging may represent a new predictor of high-risk misery perfusion, and may disappear after STA-MCA anastomosis performed in the subacute stage.
Takashi Iwase, Shoichiro Takao, Masashi Akaike, K Adachi, Y Sumitomo-Ueda, Shusuke Yagi, T Niki, Kenya Kusunose, N Tomita, Y Hirata, Koji Yamaguchi, Kunihiko Koshiba, Yoshio Taketani, Hirotsugu Yamada, Takeshi Soeki, Tetsuzo Wakatsuki, KI Aihara, Masafumi Harada, H Nishitani and Masataka Sata : Diagnostic utility of cardiac magnetic resonance for detection of cardiac involvement in female carriers of Duchenne muscular dystrophy., Heart Asia, Vol.2, 52-55, 2010.
Hideki Otsuka, Kaori Terazawa, Naomi Morita, Yoichi Otomi, Shoichiro Takao, Seiji Iwamoto, Kyosuke Osaki, Masafumi Harada and Hiromu Nishitani : Thallium-201 chloride scintigraphy in soft tissue tumors., The Journal of Medical Investigation : JMI, Vol.56, No.3-4, 136-141, 2009.
(Summary)
We report the findings of Thallium-201 chloride ((201)TlCl) scintigraphy and consider how to use this technique to evaluate the character of soft tissue lesions. We enrolled 91 consecutive patients (45 males and 46 females, age range 8-91-years-old). Nineteen patients were malignant and 72 were benign. Patients were scanned 15 minutes (early phase) and 3 hours (delayed phase) after (201)TlCl injection. More intense uptake in the lesion compared to the normal side was considered as 'high', the same degree of uptake was considered 'iso', and decreased uptake was 'low'. The retention index (RI) was calculated in 9 patients in the malignant group and in 16 patients in the benign group. In malignant tumors, 15 of 19 patients showed high uptake in both the early and delayed phases. One malignant fibrous histiocytoma patient was high only in the delayed phase and 1 liposarcoma patient was high only in the early phase. Two liposarcoma patients showed an iso uptake in both phases. One of these patients was pathologically diagnosed as a myxoid type. In benign lesions, no lipoma showed increased uptake. All neurogenic tumors except for 2 demonstrated high uptake. All 3 ganglions of the lower extremities showed iso uptake. Most inflammatory diseases showed increased uptake. Clinically-considered benign patients consisted of tumorous lesions or inflammatory disease. Only 2 patients were considered 'low', and these were diagnosed as intramuscular hematoma and cyst. RI was variable in both malignant and benign lesions and no statistically significant difference was seen between malignant and benign lesions by t-test (p=0.72). A high (201)TlCl uptake lesion is more frequently seen in malignant tumors, but regardless of whether the tumor is benign or malignant, according to the histopathological variety, the (201)TlCl uptake pattern can not be the only indicator to differentiate malignant from benign tumors. We ultimately need to evaluate the nature of tumors by a combination of several imaging techniques.
(Keyword)
Adolescent / Adult / Aged / Aged, 80 and over / children / Diagnosis, Differential / Female / Histiocytoma, Malignant Fibrous / Humans / Liposarcoma / magnetic resonance imaging / Male / Middle Aged / Radiopharmaceuticals / Soft Tissue Neoplasms / Thallium / Thallium Radioisotopes / Young Adult
Yoichi Otomi, Hideki Otsuka, Naomi Morita, Kaori Terazawa, Masafumi Harada and Hiromu Nishitani : A case of von Recklinghausen's disease with coincident malignant peripheral nerve sheath tumor and gastrointestinal stromal tumor., The Journal of Medical Investigation : JMI, Vol.56, No.1-2, 76-79, 2009.
(Summary)
(18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET/CT) was performed to evaluate a left femoral subcutaneous mass in a patient with von Recklinghausen's disease (vRd) that gradually enlarged, causing pain and numbness. The left femoral mass showed intense FDG uptake with the maximum standardized uptake value (SUVmax) of 9.0. Other subcutaneous masses considered benign and neurogenic in nature also showed FDG uptake (SUVmax around 3 or less), but the degree of FDG uptake differed considerably from the left femoral mass. This observation suggested that the degree of FDG uptake may be a useful indicator of malignant transformation. Incidentally, PET/CT also showed an asymptomatic large abdominal mass with intense FDG uptake (SUVmax 8.8). The abdominal mass was resected and confirmed as gastrointestinal stromal tumor (GIST) of the small intestine. Three months later, the left femoral mass was operated on and pathologically diagnosed as a malignant peripheral nerve sheath tumor (MPNST). Various malignant diseases are known to occur with high frequency in vRd. Therefore, vRd patients need to have periodical examinations including PET/CT. We present a rare case of a patient with vRd with a MPNST of the left femur and coincidental GIST of the small intestine. February, 2009.
Naomi Morita, Masafumi Harada, Masaaki Uno, Shunji Matsubara, Shinji Nagahiro and Hiromu Nishitani : Evaluation of Initial Diffusion-weighted Image Findings in Acute Stroke Patients using a Semiquantitative Score., Magnetic Resonance in Medical Sciences, Vol.8, No.2, 47-53, 2009.
(Summary)
We evaluated the usefulness of rating diffusion-weighted images (DWI) using a semiquantitative score modified from the Alberta Stroke Programme Early CT Score (ASPECTS) to predict deterioration of neurological symptoms in patients with hyperacute ischemic stroke who had undergone thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA). We examined 22 patients with acute stroke (14 men, 8 women, mean age 72.5 years) treated with intravenous rt-PA. All were assessed using the National Institutes of Health Stroke Scale (NIHSS) and underwent emergent magnetic resonance (MR) imaging within 3 hours and 24 hours of stroke onset. Patients were divided into a deteriorated group (16 patients), in which NIHSS scores were increased after thrombolysis, and a non-deteriorated group (6 patients). We compared the DWI score, ASPECTS, and volume of hyperintense ischemic lesion on DWI (DWI volume) of the 2 groups and examined correlations between these scores and initial NIHSS score or DWI volume. The DWI score and ASPECTS tended to be lower in the deteriorated group than the non-deteriorated group. In addition, with a cutoff value<or=7, the DWI score could discriminate the deteriorated group from the non-deteriorated group with a sensitivity of 50% and specificity of 87.5%, whereas for ASPECTS, sensitivity was 50% and specificity, 81.2%. The DWI score, ASPECTS, and DWI volume had no correlation with NIHSS score but weak negative correlations with the DWI volume (P<0.01; Spearman's test). Comparing initial NIHSS score with each DWI score and DWI volume, the non-deteriorated group tended to have higher DWI scores and smaller DWI volumes than the deteriorated group, but there was no statistical difference between initial NIHSS and DWI scores. Though the DWI score was not statistically different, the threshold would be set to 6 points or above. Comparing initial DWI score with volume, patients with low DWI scores tended to show large variation in DWI volume and patients with small DWI volume showed large variation in DWI scores. There was no relation between hemorrhagic change and symptoms in either group. The semiquantitative DWI score easily evaluated extent of acute ischemic lesion on DWI and might be used to predict patient outcome after thrombolytic therapy more accurately than ASPECTS or DWI volume.
(Keyword)
Aged / Aged, 80 and over / Diffusion Magnetic Resonance Imaging / Disease Progression / Female / Humans / Male / Middle Aged / Predictive Value of Tests / Sensitivity and Specificity / Severity of Illness Index / Stroke / Tissue Plasminogen Activator / Treatment Outcome
Shin'Ya Tayoshi, Satsuki Sumitani, Kyoko Taniguchi, Sumiko Shibuya-Tayoshi, Shusuke Numata, Jun-ichi Iga, Masahito Nakataki, Shu-ichi Ueno, Masafumi Harada and Tetsuro Ohmori : Metabolite changes and gender differences in schizophrenia using 3-Tesla proton magnetic resonance spectroscopy (1H-MRS)., Schizophrenia Research, Vol.108, No.1-3, 69-77, 2008.
(Summary)
A change in the glutamatergic system is thought to play an important role in the pathophysiology of schizophrenia. The aim of this study was to investigate the changes in metabolites, including glutamate (Glu), in the anterior cingulate cortex (ACC) and the left basal ganglia (ltBG) of patients with chronic schizophrenia using proton magnetic resonance spectroscopy ((1)H-MRS). In addition, since gender differences in this illness were known, we examined the effects of gender on these metabolites. The (1)H-MRS was performed on the ACC and ltBG of 30 patients with schizophrenia and 25 healthy individuals who acted as the control group. The levels of Glu, glutamine (Gln), creatine plus phosphocreatine (Cre), myo-inositol (mI), N-acetylaspartate (NAA), and choline-containing compounds (Cho) were measured. Two-way analysis of variance revealed that the illness significantly affected the levels of Glu and mI in the ACC; both metabolites were lower in the patients with schizophrenia as compared to the control subjects. The results also revealed that gender significantly affected the level of Gln in the ACC and the levels of Cre and NAA in the ltBG; the level of Gln in the ACC were higher in male subjects versus female subjects, whereas Cre and NAA levels in the ltBG were lower in male subjects as compared to female subjects. These results confirmed a change in the glutamatergic system and suggested an involvement of mI in the pathophysiology of schizophrenia.
(Keyword)
Adult / Analysis of Variance / Aspartic Acid / Basal Ganglia / Choline / Creatine / Female / Glutamic Acid / Gyrus Cinguli / Humans / Image Processing, Computer-Assisted / Inositol / Magnetic Resonance Spectroscopy / Male / Middle Aged / Protons / schizophrenia / Sex Characteristics / Young Adult
Kosuke Ohyama, Hitoshi Kubo, Masafumi Harada, Yuji Sasahara, Atsushi Nozaki, Naoyuki Takei, Shoichiro Takao and Hiromu Nishitani : [Comparison of 3 Tesla whole heart coronary MRA (WHCA) with 1.5 Tesla], Japanese Journal of Radiological Technology, Vol.64, No.12, 1540-1546, 2008.
(Summary)
Whole heart coronary MRA (WHCA) is a noninvasive method used to image all coronary arteries with cardiac and real-time respiratory gating. We compared the coronary depiction ability of 3T WHCA with that of 1.5T using healthy volunteers. In addition, we compared the study performance rate, which might differ at 3T and 1.5T due to the difference in specific absorption rate (SAR) limits. The coronary artery was classified into nine segments, based on the classification of the American Heart Association (AHA). Each observer was asked to evaluate WHCA with the three-point scale rating for each segment, and to measure the visible length of each coronary artery utilizing reconstructed CPR and VR images. Depiction at 3T was superior to that at 1.5T. The completion rate of study was 100% at 1.5T, but just 63% at 3T owing to SAR limits. Thus it was suggested that 3T WHCA might be feasible with the advantage of high depiction ability, if adequate SAR reduction techniques were developed.
(Keyword)
Coronary Vessels / Humans / Image Processing, Computer-Assisted / Magnetic Resonance Angiography / Male / Observer Variation / Young Adult
Naomi Morita, Masafumi Harada, Masaaki Uno, Shunji Matsubara, Shinji Nagahiro and Hiromu Nishitani : Ischemic Findings of T2*-Weighted 3-Tesla MRI in Acute Stroke Patients., Cerebrovascular Diseases, Vol.26, No.4, 367-375, 2008.
(Summary)
We compared ischemic findings on gradient echo-type T(2)*-weighted images at 3-tesla MRI (T(2)*WI) in patients with acute ischemia and major vessel occlusion, and stroke patients with lacunar infarction or branch atheromatous disease. Our study population consisted of 45 patients with acute stroke. They underwent 3-tesla MRI within 12 h of stroke onset. Included were 24 patients (13 men and 11 women, mean age 68 years) with major vessel occlusion and 21 patients (11 men and 10 women, mean age 69 years) with minor infarction such as lacunar infarcts or branch atheromatous disease. We classified vascular ischemic findings of T(2)*WI into 3 sign categories, i.e. artery susceptibility sign, cortical vessel sign (hypointensity and enlargement of the cortical vessels) and brush sign (hypointensity of vessels in the deep white matter). Decreased intensity in the ischemic parenchyma was designated ischemic tissue sign. We compared regions of interest in the hypoperfused area on flow-sensitive alternating inversion recovery (FAIR) images with our vascular ischemic findings. None of the vascular ischemic signs nor the ischemic tissue sign were found in patients with minor vessel disease. All 24 patients with major vessel occlusion manifested the cortical vessel sign, 23 the brush sign. The area with ischemic vessel signs on T(2)*WI was almost as large or somewhat smaller than the hypoperfused area on FAIR images. Compared to the contralateral side, 14 of 24 patients (58.3%) with major vessel occlusion showed decreased intensity in the ischemic parenchyma (ischemic tissue sign). Region of interest measurements on FAIR images demonstrated greater hypoperfusion in the area classified as ischemic tissue sign on T(2)*WI. Ischemic vessel signs and the ischemic tissue sign on T(2)*WI at 3 T would be useful to evaluate the extensive ischemia due to major vessel occlusion and may be correlated with the blood-oxygen-level-dependent effect due to increased deoxyhemoglobin. The ischemic tissue sign may be reflective of severe ischemia.
(Keyword)
Acute Disease / Adult / Aged / Aged, 80 and over / Brain Infarction / Brain Ischemia / Cerebral Angiography / Echo-Planar Imaging / Female / Hemoglobins / Humans / Male / Middle Aged / Severity of Illness Index / Stroke
Yoshihiro Takegawa, Hitoshi Ikushima, Kyosuke Osaki, Shunsuke Furutani, Takashi Kawanaka, Takaharu Kudoh and Masafumi Harada : Can Kampo Therapy prolong the life of cancer patients?, The Journal of Medical Investigation : JMI, Vol.55, No.1,2, 99-105, 2008.
(Summary)
Our policy regarding the performance of radiotherapy to squamous cell carcinoma of the uterine cervix has not changed since 1969. We have already reported the treatment results which were as good as those from other institutions. Since 1978, Kampo therapy was first introduced in the treatment of cancer patients in dealing with problems such as the side effects of radiotherapy and chemotherapy and various types of general malaise. We analyzed our treatment results in order to re-evaluate the chemo-radiotherapy in combination with Kampo. Survival rates for 5, 10 and 15 years, respectively, were 90.9%, 71.6% and 71.6% for Stage IB, 78.9%, 61.8% and 41.8% for Stage II, 62.3%, 49.1% and 41.2% for Stage III and 53.1%, 36.5% and 16.7% for Stage IV. The Kampo significantly extended the survival of patients with uterine cervical cancer. We intend to perform further research with more patients to explore how this therapy contributes to the prolonging of patients survival.
(Keyword)
Adult / Aged / Aged, 80 and over / Carcinoma, Squamous Cell / Combined Modality Therapy / Drugs, Chinese Herbal / Female / Follow-Up Studies / Humans / Medicine, Kampo / Middle Aged / Neoplasm Staging / Phytotherapy / Quality of Life / Retrospective Studies / Survival Rate / Time Factors / Treatment Outcome / Uterine Cervical Neoplasms
Aoi Matsuoka, Masako Minato, Masafumi Harada, Hitoshi Kubo, Yoshikatsu Bandou, Akira Tangoku, Kiichirou Nakano and Hiromu Nishitani : Comparison of 3.0-and 1.5-tesla diffusion-weighted imaging in the visibility of breast cancer., Radiation Medicine, Vol.26, No.1, 15-20, 2008.
(Summary)
PURPOSE: The aim of this study was to compare diffusion-weighted imaging (DWI) at 3.0 T and 1.5 T by evaluating the apparent diffusion coefficient (ADC) value and visibility of breast cancer in the same patients. MATERIALS AND METHODS: A total of 13 patients (16 lesions) with breast cancer underwent DWI at 3.0 T and 1.5 T. Tumors were classified into two groups based on the lesion size. The ADC values were measured, and visibility of the tumors was scored blindly. RESULTS: No significant difference was found for ADC values between 3.0 T and 1.5 T in either group (P > 0.05). All of the large lesions were visible clearly at both magnetic field strengths, and image scores were not different (P > 0.05). In contrast, small lesions were more clearly visible and had better image scores at 3.0 T than at 1.5 T (P < 0.001). CONCLUSION: Small cancers were more clearly visible on DWI at 3.0 T than 1.5 T.
(Keyword)
Breast Neoplasms / Diffusion Magnetic Resonance Imaging / Female / Humans / Image Interpretation, Computer-Assisted
Masaaki Uno, Atsuhiko Suzue, Kyoko Nishi, Naomi Morita, Masafumi Harada, Yuishin Izumi, Shunya Nakane and Shinji Nagahiro : Diagnosis and Treatment in Stroke Center of Tokushima University Hospital : Efficacy of 3 Tesla Stroke MRI(<Topic> Stroke Care Unit, Stroke Center), Surgery for Cerebral Stroke, Vol.35, No.6, 427-431, 2007.
(Summary)
After the stroke care unit of Tokushima University hospital was established in November 1999, stroke MRI (diffusion-, perfusion-weighted image, MRA) was performed to initially evaluate stroke patients, except for SAH. Since April 2004, 3 tesla MRI has been used for stroke MRI, and T2^* weighted image was added to routine study of stroke MRI. 3 tesla stroke MRI can reduce examination time and also take functional MR images, which yield important information for diagnosis and treatment decisions. The combination of our stroke center and rehabilitation hospital is a key factor in improving patients' outcomes for acute rehabilitation and improving quality of life.
Naomi Morita, Masafumi Harada, Masaaki Uno, Hiromu Nishitani and Shinji Nagahiro : Diagnosis of acute stroke patients: using MRI as the first selected modality, Japanese Journal of Clinical Radiology, Vol.52, 1663-1669, 2007.
Masaaki Uno, Naomi Morita, Masafumi Harada and Shinji Nagahiro : 3T-MRIによるStroke MRIの現状と問題点 脳梗塞急性期治療の最前線ー血栓溶解療法の新たな展開ー, The Mt.Fuji Workshop on CVD, Vol.25, 39-42, 2007.
223.
Masafumi Harada, Naomi Morita, Hiromu Nishitani, Masaaki Uno, Shinji Nagahiro, Shunya Nakane, Yuishin Izumi and Ryuji Kaji : 1.5 Tesla Stroke Unit MRI: 画像診断の新展開, 分子脳血管病, Vol.6, 258-263, 2007.
224.
Naomi Morita, Masafumi Harada, Masaaki Uno, Hiromu Nishitani and Shinji Nagahiro : The usefulness and problem for MR I examination by using clinical 3T-MRI, DIGITAL MEDICINE, Vol.7, 6-9, 2007.
225.
Naomi Morita, Masafumi Harada, Masaaki Uno, Kaori Furutani and Hiromu Nishitani : Change of Diffusion Anisotropy in Patients with Acute Cerebral Infarction Using Statistical Parametric Analysis, Radiation Medicine, Vol.24, No.4, 253-259, 2006.
(Summary)
We conducted statistical parametric comparison of fractional anisotropy (FA) images and quantified FA values to determine whether significant change occurs in the ischemic region. The subjects were 20 patients seen within 24 h after onset of ischemia. For statistical comparison of FA images, a sample FA image was coordinated by the Talairach template, and each FA map was normalized. Statistical comparison was conducted using SPM99. Regions of interest were set in the same region on apparent diffusion coefficient (ADC) and FA maps, the region being consistent with the hyperintense region on diffusion-weighted images (DWIs). The contralateral region was also measured to obtain asymmetry ratios of ADC and FA. Regions with areas of statistical significance on FA images were found only in the white matter of three patients, although the regions were smaller than hyperintense regions on DWIs. The mean ADC and FA ratios were 0.64 +/- 0.16 and 0.93 +/- 0.09, respectively, and the degree of FA change was less than that of the ADC change. Significant change in diffusion anisotropy was limited to the severely infarcted core of the white matter. We believe statistical comparison of FA maps to be useful for detecting different regions of diffusion anisotropy.
(Keyword)
Acute Disease / Aged / Aged, 80 and over / Algorithms / Anisotropy / Cerebral Infarction / Computer Simulation / Data Interpretation, Statistical / Diffusion Magnetic Resonance Imaging / Female / Humans / Image Enhancement / Image Interpretation, Computer-Assisted / Information Storage and Retrieval / Male / Middle Aged / Models, Biological / Models, Statistical / Reproducibility of Results / Sensitivity and Specificity
Ryou Urushihara, Nagako Murase, C John Rothwell, Masafumi Harada, Yuki Hosono, Kotaro Asanuma, Hideki Shimazu, Kazumi Nakamura, Sachiko Chikahisa, Kazuyoshi Kitaoka, Hiroyoshi Sei, Yusuke Morita and Ryuji Kaji : Effect of repetitive transcranial magnetic stimulation applied over the premotor cortex on somatosensory-evoked potentials and regional cerebral blood flow., Neuroimage, Vol.31, No.2, 699-709, 2006.
(Summary)
Somatosensory-evoked potentials (SEPs) are attenuated by movement. This phenomenon of 'gating' reflects sensorimotor integration for motor control. The frontal N30 component after median nerve stimulation was shown to be reduced in amplitude prior to hand movement. To investigate the mechanism of this sensory gating, we recorded median SEPs immediately before and after application of monophasic very low-frequency (0.2 Hz) repetitive transcranial magnetic stimulation (rTMS) of 250 stimuli over motor cortex (MC), premotor cortex (PMC), or supplementary motor area (SMA) in 9 healthy volunteers. The stimulus intensity for MC or PMC was set 85% of the resting motor threshold for the hand muscle, and that for SMA was at the active motor threshold for the leg muscle. SEPs showed significant increases in amplitudes of the frontal N30 component after PMC stimulation, but not after SMA or MC stimulation. Low-frequency (1 Hz) biphasic stimulation over PMC showed no significant N30 changes in 6 out of 9 subjects tested, indicating the effect being specific for 0.2 Hz monophasic stimulation. To examine the functional anatomy of the N30 change, single photon emission computed tomography was performed immediately before and after monophasic 0.2 Hz rTMS over PMC in all the 9 subjects. Regional cerebral blood flow showed significant increases mainly in PMC and prefrontal cortex, indicating the involvement of these cortical areas in sensory input gating for motor control.
Mayumi Takeuchi, Kenji Matsuzaki, Masafumi Harada, Hiromu Nishitani and Matsuda Tsuyoshi : Cerebral hyperperfusion in a patient with eclampsia with perfusion-weighted magnetic resonance imaging, Radiation Medicine, Vol.23, No.5, 376-379, 2005.
(Summary)
The patient was a 25-year-old Japanese woman with postpartum eclampsia, in whom magnetic resonance imaging (MRI) was performed ten hours after convulsion. The patient improved within three days. Diffusion-weighted images showed a high apparent diffusion coefficient (ADC), and perfusion-weighted images obtained by the multi-slice flow-sensitive alternating inversion recovery (FAIR) method showed hyperperfusion, which was suggestive of vasogenic edema, on the parietal and occipital subcortical white matter, corresponding with transient hyperintensities on T2-weighted images. MR angiography (MRA) revealed no signs of vasospasm. These findings suggested hyperperfusion-induced vasogenic edema without cerebrovascular spastic change in the early stage of eclampsia. The FAIR method is considered a useful technique for perfusion-weighted MRI, especially useful to evaluate the cerebral perfusion of emergency patients such as those with eclampsia.
Kaori Furutani, Masafumi Harada, Masako Minato, Naomi Morita and Hiromu Nishitani : Regional changes of fractional anisotropy with normal aging using statistical parametric mapping (SPM)., The Journal of Medical Investigation : JMI, Vol.52, No.3,4, 186-190, 2005.
(Summary)
There has been reports on the usefulness of diffusion tensor imaging (DTI) about age-or disease-related degradation. DTI is generally evaluated by the region of interest (ROI) methodology. In this study, we applied a statistical way using Statistical Parametric Mapping (SPM) to assess normal aging by DTI and compared results of these two methods. Ten young and ten senior normal volunteers were examined. On SPM, tensor images were changed into normalized tensor images. They were compared between the two groups by t-test. In the senior group, fractional anisotropy (FA) values were higher on the basal ganglia, cingulated gyrus and other cortical gray matter, lower in the corona radiata, internal capsule, centrum semiovale and corpus callosum by using SPM. In the ROI method, the results were almost compatible except in the brain periphery. Aging changes on water diffusion anisotropy was clearly shown by SPM method which would be useful to evaluate change of water diffusion anisotropy without operator bias even in clinical setting instead of ROI measurement.
Masaaki Uno, 里見 淳一郎, 鈴江 淳彦, 中嶌 敦夫, 佐藤 浩一, 永廣 信治, 米田 和英, 森田 奈緒美 and Masafumi Harada : Diagnosis and treatment of patients with acute cerebral ischemia using stroke MRI, Surgery for Cerebral Stroke, Vol.32, No.4, 262-266, 2004.
(Summary)
Between November 1999 and September 2002, 175 patients with acute cerebral infarction were admitted to our Stroke Care Unit. Stroke MRI (Diffusion-, perfusion- and T2-weighted imaging and MR angiography) was performed for these patients, and we used diffusion/perfusion mismatch for indication of cardiovascular reconstruction. Of 175 patients, 44 were diagnosed as atherothrombotic infarction, 70 as cardioembolic infarction and 57 as lacunar infarction. In 19 patients (27.1%) of cardioembolic infarction and 17 (38.6%) of atherothrombotic infarction, cerebrovascular reconstructions were performed. Although outcome after treatment was good in only 3 of these 19 patients (15.8%) with cardioembolism, out,come was good in 13 of 17 (76.5%) with atherothrombotic infarction. Outcomes of patients with cardioembolic internal carotid occlusion were very poor even if stroke MRI indicated acute thrombolysis, because almost all thrombolysis were failed. In conclusion, stroke MRI accurately diagnosed acute cerebrai infarction, and acute and subacute cerebrovascular reconstruction induced good outcome in patients with atherothrombotic infarction.
(Keyword)
cerebral infarction / diffusion-weighted imaging / perfusion-weighted imaging / stroke care unit / treatment
Mayumi Takeuchi, Masafumi Harada, Kenji Matsuzaki, Hiromu Nishitani and Kenji Mori : Difference of signal change by a language task on autistic patients using functional MRI, The Journal of Medical Investigation : JMI, Vol.51, No.1-2, 59-62, 2004.
(Summary)
OBJECTIVE: Cerebral function with a language task was evaluated by functional magnetic resonance imaging (MRI), and the differences of activated pattern and signal changes were compared between autistic patients and normal controls. METHODS: Ten autistic and ten normal subjects were tested by fMRI with a language task requiring the attribution of complex mental states. Activation maps analyzed between two groups were generated and the asymmetry indexes calculated by the quotient of activated pixels of the right frontal lobe divided by those of the left frontal lobe were statistically compared by unpaired t-test. RESULTS: Both the autistic and the normal subjects showed activation at the bilateral prefrontal cortical areas and the ventral occipito-temporal regions. However, the autistic patients demonstrated more activation at the right frontal lobe than the normal controls. Thus it was considered that in the autistic patients the right-hemisphere was more dominant for the language task than that of the normal controls. The result is consist to the theory that autism is related to early left-hemisphere dysfunction. CONCLUSIONS: We considered that fMRI may be a useful non-invasive method to evaluate the cerebral functional abnormality in autistic patients.
(Keyword)
Adolescent / Autistic Disorder / Brain / Case-Control Studies / Child / Female / Humans / Language / Language Tests / Magnetic Resonance Imaging / Male
Kanji Kusunoki, Masahiro Nomura, Norihito Kageyama, Akiyoshi Nisikado, Masafumi Harada, Yutaka Nakaya and Susumu Ito : Detection of coronary arterial microvascular discorders using 99mTc-tetrofosm in uptake increase during exercise and coronary blood flow velocity patterns obtained by magnetic resonance imaging., Heart and Vessels, Vol.19, No.1, 1-7, 2004.
(Summary)
This study reports an evaluation of coronary arterial blood flow patterns in patients with diabetes mellitus and healthy subjects using magnetic resonance coronary angiography (MRCA). Twenty patients with diabetes mellitus (DM group) and 20 healthy subjects (N group) were studied using MRCA and myocardial SPECT images using (99m)Tc-tetrofosmin (TF). The rate of change in myocardial TF uptake was measured during a 1-day protocol of exercise and rest. Initial and delayed exercise single photon emission computed tomography (SPECT) images were acquired 30 min and 3 h after injection (370 MBq of TF) (TF1 and TF2, respectively). Thereafter, 740 MBq of TF was administered intravenously, again, and resting SPECT images (TF3) were acquired 30 min later. The myocardial counts of these three points of acquisition were defined, and the rate of change of myocardial TF uptake between exercise and rest was determined. The % increase in uptake was significantly lower in the DM group than in the N group in all myocardial segments. The average coronary arterial diastolic velocity determined using MRCA was slightly lower in the DM group than in the N group, and the average systolic peak velocity (ASPV) was slightly greater in the DM group than in the N group, although these values were not statistically significant. The diastolic/systolic velocity ratio (DSVR) in the DM group was significantly lower than that in the N group ( P < 0.05). There was a significant correlation between DSVR and % uptake increase ( r = 0.605, P < 0.05). These results indicate that the measurements made using MRCA and the % uptake increase measured using TF myocardial scintigraphy represent a potentially useful noninvasive method for diagnosing microvascular dysfunction in diabetic patients.
Kazuhide Yoneda, Masafumi Harada, Naomi Morita, Hiromu Nishitani, Masaaki Uno and Tsuyoshi Matsuda : Comparison of FAIR technique with different inversion times and post contrast dynamic perfusion MRI in chronic occlusive cerebrovascular disease, Magnetic Resonance Imaging, Vol.21, No.7, 701-705, 2003.
(Summary)
The purpose of this study was to examine the signal change occurring with different inversion times (TIs) of the flow-sensitive alternating inversion recovery (FAIR) technique and to compare with the perfusion image obtained with Gd-DTPA injection. The subjects were 11 patients with unilateral occlusive cerebrovascular disease. Two FAIR images with different TIs (800 ms and 1600 ms) were measured for each patient and dynamic perfusion MRI was performed to produce four kinds of parameter maps: mean transit time (MTT), time to peak (TTP), relative cerebral blood flow (rCBF) and relative cerebral blood volume (rCBV) maps. Asymmetry ratios (ARs) between the affected and contra-lateral vascular sides were measured in both FAIR images and the four dynamic parameter maps. The AR of the MTT map of the four parameters showed the highest correlation with that of the FAIR images, especially with that of TI = 1600 ms (r = 0.829), and the AR of the rCBV map revealed the worst correlation with the FAIR images. The AR of the FAIR image with TI = 800 ms was less correlated with that of MTT than that with TI = 1600 ms. These results suggested that the signal intensity of the FAIR image was influenced by flow transition time and the change in TI could be used to select the flow with a different transition time. Our study suggested that a longer TI in the FAIR technique might be more useful than a shorter TI for evaluating chronic occlusive cerebrovascular disease in the clinical setting.
Mayumi Takeuchi, Masafumi Harada and Hiromu Nishitani : Magnetic resonance imaging and proton MR spectroscopy of the brain in a patient with carbohydrate-deficient glycoprotein syndrome type I., Journal of Magnetic Resonance Imaging : JMRI, Vol.17, No.6, 722-725, 2003.
(Summary)
This is a report on a case of carbohydrate-deficient glycoprotein syndrome (CDGS) with neurological deficits. Magnetic resonance (MR) images showed remarkable atrophy of the cerebellum and brainstem, and hypointensity was seen in the pallidum on diffusion-weighted images (DWI), suggesting deposits of metal substances. In the cerebellum, proton MR spectroscopy (MRS) showed decreased concentrations of N-acetylaspartate and a complex of glutamine and glutamate (Glx) while the concentration of myo-inositol was increased, indicating neuronal impairment and gliosis. In the parietal lobe, there was an increased concentration of Glx, possibly reflecting dysfunction caused by liver injury.
(Keyword)
Adolescent / Brain / Congenital Disorders of Glycosylation / Humans / Magnetic Resonance Imaging / Magnetic Resonance Spectroscopy / Male
H. Toi, Masaaki Uno, Masafumi Harada, Kazuhide Yoneda, Naomi Morita, Shunji Matsubara, Koichi Satoh and Shinji Nagahiro : Diagnosis of acute brain-stem infarcts using diffusion-weighed MRI, Neuroradiology, Vol.45, No.6, 352-356, 2003.
(Summary)
There are many reports on acute cerebral infarcts diagnosed by diffusion-weighted MRI (DWI), but few describe brain-stem infarcts diagnosed by this method. Using the apparent diffusion coefficient (ADC), we studied 18 consecutive patients with brain-stem infarcts who underwent DWI during the acute phase. We calculated and compared the ADC ratio (lesion ADC/contralateral ADC) in 10 patients with brain-stem and 23 with supratentorial cortical infarcts examined within 24 h of the onset of stroke. Ischaemic brain-stem lesions were detected in all 15 patients who underwent DWI more than 3 h after the onset, but not in two who had DWI within 3 h of the onset; their ADC ratio was more than 0.95. ADC ratios in patients with brain-stem infarcts decreased as the interval between onset and DWI increased; the decrease was slower than in patients with supratentorial cortical infarcts.
Manabu Kinoshita, Masahiro Nomura, Masafumi Harada, Shigenobu Bando, Yutaka Nakaya and Susumu Ito : Myocardial perfusion magnetic resonance imaging for diagnosing coronary arterial stenosis:evaluation by signal-intensity time curves, Japanese Heart Journal, Vol.44, No.3, 323-334, 2003.
(Summary)
It has been reported that myocardial perfusion MRI is a useful method for evaluating the severity of myocardial ischemia. We evaluated whether the severity of coronary arterial stenosis could be assessed by the signal-intensity time curve (SITC) obtained by myocardial perfusion MRI.br The subjects consisted of 10 patients who showed no abnormalities on coronary angiographies (CAG) (A group), 12 with single-vessel disease of 75-90% stenosis on CAG (B group), and 15 with single-vessel disease of 90% or more stenosis (C group). After infusion of dipyridamole for 4 minutes, gadolinium-diethylenetriamine pentaacetic acid was administered intravenously, followed by serial acquisition of T1-weighted left ventricular short-axis MR images. These images were evaluated after dividing them into the following 3 myocardial segments: anterior wall, lateral wall, and inferior wall. Mean values of the slope of SITC (1.4 ± 0.2 vs 1.1 ± 0.2, iP /i 0.01), and increases to the peak corrected SI (ΔSI) (47.5 ± 1.9 % vs 33.7 ± 2.4%, iP/i 0.01) in normal myocardial segments were significantly greater than in ischemic segments in the C group, while there was no significant distinction between normal and ischemic segments in the B group. The mean values of time to the peak SI were not significantly different between normal and ischemic regions in the B and C groups.br The results suggest that myocardial segments exhibiting 30% decreases in both the slope and ΔSI of SITC can be diagnosed as having 90% or more severe coronary stenosis. The present study shows that visual and SITC evaluations of myocardial perfusion MR images may be useful for clinically evaluating the severity of coronary stenosis.br
Mayumi Takeuchi, Masafumi Harada, Kenji Matsuzaki and Hiromu Nishitani : Magnetic resonance imaging and spectroscopy in a patient with treated methylmalonic acidemia., Journal of Computer Assisted Tomography, Vol.27, No.4, 547-551, 2003.
(Summary)
Magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (proton MRS) findings before and after carnitine therapy in a patient with methylmalonic acidemia (MMA) are evaluated. The hyperintensity on T2-weighted image and diffusion-weighted image and the decreased apparent diffusion coefficient of bilateral basal ganglia were normalized in parallel with normalization of the elevated lactate levels and the decreased N-acetyl-aspartate levels, corresponding to improvement of clinical symptoms. MRI and proton MRS may serve as a suitable, noninvasive modality for monitoring treated MMA.
Hitoshi Kubo, Masafumi Harada, Minoru Sakama and Hiromu Nishitani : Reproducibility of Metabolite Concentration Evaluated by Intraclass Correlation Coefficient Using Clinical MR Apparatus., Journal of Computer Assisted Tomography, Vol.27, No.3, 449-453, 2003.
(Summary)
The purpose of this study was to evaluate the reproducibility of in vivo quantitative proton MR spectroscopy (MRS) by repeated-measure analysis of variance and intraclass correlation coefficient (ICC) including assessment of both inter- and intrasubject variation. The concentration of metabolites was quantified using long-TR and short-TE stimulated-echo acquisition mode sequences with a quadrature head coil. All preparation procedures for MRS measurement except volume of interest determination were done by an automatic preparation scanning system equivalent to a clinical setting. Analyses were conducted by an LCModel running based on our original basis set by two different reference methods. The ICC showed a good correlation (r = 0.61-0.99) in any metabolite and almost the same value between the two different reference methods, but the concentration of myoinositol had a large intersubject variation. Our results suggest that the reproducibility of quantified metabolite concentration is acceptable in the clinical setting regardless of the reference method, although quantified values may have different intersubject variations.
Naomi Morita, Masafumi Harada, Kazuhide Yoneda, Hiromu Nishitani and Masaaki Uno : A characteristic feature of acute haematomas in the brain on echo-planar diffusion-weighted imaging, Neuroradiology, Vol.44, No.11, 907-911, 2002.
(Summary)
Diffusion-weighted MRI (DWI) is used in the diagnosis of acute ischaemic disease of the brain, but it is not clear whether or not it can be used to differentiate an acute haematoma from an infarct. Our purpose was to identify any characteristic feature of acute haematomas which can be recognised on DWI and to evaluate the usefulness of DWI in acute cerebral stroke. We examined nine patients with acute haemorrhage using CT and MRI including DWI. We measured the volume and apparent diffusion coefficient (ADC) of the haematomas. All showed heterogeneous signal on DWI, and the centre of the large (>20 ml) haematomas especially a mixed pattern with high and low signal. The characteristic feature of acute haematomas was a peripheral low-signal region, found in all subjects regardless of the size of the haematoma; acute infarcts did not show this. This low-signal rim on DWI may be useful for differentiating an acute haematoma from an infarct.
Kazuhiro Mori, Masafumi Harada and Yasuhiro Kuroda : Twisted atrioventricular valves in double inlet left ventricle, Cardiology in the Young, Vol.12, No.4, 401-403, 2002.
(Summary)
Twisted atrioventricular connections usually occur in hearts with biventricular artioventricular connections. Here, we describe a case of twisted atrioventricular valves associated with double inlet left ventricle and discordant ventriculo-arterial connections. Color Doppler echocardiography, and cine magnetic resonance imaging, clearly demonstrated that the right atrioventricular valve was located anterior and superior to the left atrioventricular valve, and that the axes of the two atrioventricular valves crossed each other within the dominant left ventricle.
(Keyword)
Criss-cross heart / functionally univentricular heart / magnetic resonance imaging
Masafumi Harada, Masaaki Uno, Fang Hong, Sonoka Hisaoka, Hiromu Nishitani and Tsuyoshi Matsuda : Diffusion-weighted in vivo localized proton MR spectroscopy of human cerebral ischemia and tumor, NMR in Biomedicine, Vol.15, No.1, 69-74, 2002.
(Summary)
The apparent diffusion coefficients (ADCs) of water and brain metabolites were determined by proton MR spectroscopy on a clinical MR scanner for healthy volunteers and for pathological changes in cases of acute cerebral infarction and brain tumor. The ADCs of N-acetyl aspartate (NAA) and creatines in tissue involved in acute infarction were decreased compared to normal control values, while in tumors they showed increased values. Since NAA is a neuronal marker, these findings suggest that neuronal cell viscosity changes according to the pathological status of the tissue. The lactate ADC was significantly larger than the values for other major metabolites in cases of ischemia and tumor, suggesting that lactate is present in a different compartment. These results indicate that metabolite diffusion data can be used to reveal changes in the intracellular environment depending on the pathological status.
Masaaki Uno, Masafumi Harada, Kazuhide Yoneda, Shunji Matsubara, Koichi Satoh and Shinji Nagahiro : Can Diffusion- and Perfusion-weighted Magnetic Resonance Imaging Evaluate the Efficacy of Acute Thrombolysis in Patients with Internal Carotid Artery or Middle Cerebral Artery Occlusion?, Neurosurgery, Vol.50, No.1, 34-35, 2002.
(Summary)
The value of combined diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) for detecting ischemic lesions of patients with acute ischemic injury was analyzed. Combined pre- and posttreatment DWI and PWI studies were used to assess the efficacy of intra-arterial thrombolysis. Intra-arterial thrombolysis was performed within 6 hours of onset in 10 patients who presented with acute middle cerebral artery or internal carotid artery occlusion. DWI and PWI obtained before and after treatment were studied. The final T2-weighted magnetic resonance scans were obtained 1 month after onset. Thrombolysis resulted in recanalization in seven patients. The mismatch ratio percentage ([initial PWI-initial DWI/initial PWI] x 100) and the rescued ratio percentage ([initial PWI-final T2/initial PWI] x 100) were calculated. The National Institutes of Health Stroke Scale (NIHSS) was used for neurological assessment of stroke severity at admission and at 1 month after onset. In all patients, the mismatch ratio was greater than 60% (mean +/- standard deviation, 81.7 +/- 16.7%) and was significantly correlated with initial NIHSS score (-0.74; P = 0.03), and the rescued ratio was significantly correlated with the NIHSS score 1 month after the insult (r = -0.83; P = 0.01). In patients who exhibited recanalization of the occluded artery (n = 7), the mean rescued ratio was 89.6 +/- 12.8% (range, 63-100%). In addition, the lesion volume on posttreatment DWI scans and final T2-weighted magnetic resonance images was not enlarged; on posttreatment PWI scans, it was significantly decreased. The NHISS score at 1 month after the insult (2.3 +/- 2.1) was markedly improved as compared with the initial NHISS score (10.7 +/- 3.9). In a small number of patients who presented with internal carotid artery or middle cerebral artery occlusion, the DWI/PWI mismatch ratio correlated with the initial neurological severity. The rescued ratio may be an objective indicator of the efficacy of treatment.
(Keyword)
Diffusion-weighted magnetic resonance imaging / Intra-arterial thrombolysis / Perfusion-weighted magnetic resonance imaging
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● PubMed @ National Institutes of Health, US National Library of Medicine (PMID): 11844231
Masafumi Harada, Satsuki Sumitani, Hitoshi Kubo, 岡田 稔子, Hiromu Nishitani and Tetsuro Ohmori : 強迫性障害におけるproton MRSによる評価, Japanese Journal of Magnetic Resonance in Medicine, Vol.22, No.Suppl, 248, 2002.
245.
Masaaki Uno, Masafumi Harada and Shinji Nagahiro : Quantitative evaluation of cerebral metabolites and cerebral blood flow in patients with carotid stenosis, Neurological Research, Vol.23, No.6, 573-580, 2001.
(Summary)
We examined the metabolic and hemodynamic status of patients with severe carotid stenosis and evaluated the effectiveness of carotid endarterectomy (CEA) by comparing pre- and post-operative results of quantitative proton magnetic resonance spectroscopy (1H-MRS) and single-photon emission computed tomography (SPECT). Quantitative 1H-MRS and SPECT were performed in 17 patients with severe carotid stenosis before CEA; in 10 patients the examinations were repeated after CEA. There was a significant correlation between the degree of internal carotid artery (ICA) stenosis and the N-acetyl-aspartate (NAA) concentration, and between CBFand NAA in the basal ganglia. In 10 of the 17 patients (58.8%) we noted a decrease of NAA on 1H-MRS. After CEA in these patients, NAA was significantly increased, and in 7 of 8 patients whose pre-operative SPECT had indicated impairment of cerebral vasoreactivity, it was improved. Quantitative 1H-MRS and CBF measurements can indicate the severity of metabolic and hemodynamic impairment in patients with severe carotid stenosis, and can help to assess the effectiveness of CEA.
(Keyword)
CAROTID ENDARTERECTOMY / CAROTID STENOSIS / PROTON MAGNETIC RESONANCE SPECTROSCOPY / SINGLE PHOTON EMISSION / COMPUTED TOMOGRAPHY
Masafumi Harada, H. Miyosh, Hideki Otsuka, Hiromu Nishitani and M. Uno : Multivariate analysis of regional metabolic differences in normal ageing on localised quantitative proton MR spectroscopy, Neuroradiology, Vol.43, No.6, 448-452, 2001.
Toshiko Okada, Masafumi Harada, Kenji Matsuzaki, Hiromu Nishitani and Toshihiro Aono : Evaluation of female intrapelvic tumors by clinical proton MR spectroscopy., Journal of Magnetic Resonance Imaging : JMRI, Vol.13, No.6, 912-917, 2001.
(Summary)
We measured metabolites in large tumors of the female pelvis (23 cases total: 6 malignant cases, 17 benign cases) using single-voxel proton magnetic resonance (MR) spectroscopy and evaluated the clinical significance of this method in the differential diagnosis of female pelvic tumors. The characteristically obtained signal was lactate, which was detected not only in all the malignant tumors but also in some of the benign tumors. However, the lactate signals of the malignant tumors tended to form higher peaks than those of benign tumors, which was a finding consistent with the result of the earlier in vitro study reported in ovarian tumors. The signal of choline-containing compounds (Cho) was found only in solid tumors, and the signal intensity varied among different histological types of tumors, possibly reflecting metabolic activity of the cell membrane. We considered that proton MR spectroscopy (MRS) of intrapelvic tumors would be useful for the diagnosis of the nature of female intrapelvic tumors. J. Magn. Reson. Imaging 2001;13:912-917.
(Keyword)
Adult / Aged / Aged, 80 and over / Choline / Creatine / Diagnosis, Differential / energy metabolism / Female / Humans / Lactic Acid / Lipid Metabolism / magnetic resonance imaging / Magnetic Resonance Spectroscopy / Male / Middle Aged / Ovarian Neoplasms / ovary / Sensitivity and Specificity / Uterine Neoplasms / uterus
Hitoshi Miyajima, Masahiro Nomura, Naoki Muguruma, Toshiya Okahisa, Seisuke Okamura, Hirohito Honda, Ichiro Shimizu, Masafumi Harada, Ken Saito, Yutaka Nakaya and Susumu Ito : Relationship among gastric motility,autonomic activity,and portal hemodynamics in patients with liver cirrhosis, Journal of Gastroenterology and Hepatology, Vol.16, No.6, 647-659, 2001.
(Summary)
We examined the effects of the autonomic nervous function and the volume of portal blood flow to clarify the mechanism of the abnormal gastric motility in patients with liver cirrhosis. Heart rate variability, electrogastrogram (EGG), and volume of portal blood flow were measured before and after a meal in 27 patients with liver cirrhosis (LC group) and in 20 normal subjects (N group). Autonomic nervous function was evaluated by using spectral analysis of heart rate variability. We used the cine phase-contrast (PC) method, using magnetic resonance imaging (MRI) to measure the portal flow, while the peak frequency and spectral power of the EGG were measured at pre- and postprandial change. The ratio of low frequency power to high frequency power (LF/HF) was significantly higher, and the HF power was significantly lower in the LC group than in the N group both before and after a meal. In both groups, the electrogastrographic peak power ratio before and after a meal showed a positive correlation with the HF ratio, and an inverse correlation with the LF/HF ratio. In addition, portal blood flow volume was significantly decreased in the LC group than in the N group. However, the increased rate of portal blood flow after a meal correlated positively with the increased rate of electrogastrographic peak power. Moreover, gastric motility was positively correlated with esophageal varices and coma scale with the use of multivariate analysis. Parasympathetic hypofunction, sympathetic hyperfunction and portal hemodynamics were closely related with gastric motility in cirrhotic patients. In addition, gastric motility was decreased, at least in part, by the ingestion of food in cirrhotic patients because of abnormalities in autonomic functions and portal blood flow following a meal.
(Keyword)
Aged / Autonomic Nervous System / Electrophysiology / Female / Gastrointestinal Motility / Heart Rate / Hemodynamics / Humans / Liver Cirrhosis / Magnetic Resonance Imaging / Male / Middle Aged / Portal System
Toshihiro Toyoshima, Masahiro Nomura, Akiyoshi Nishikado, Masafumi Harada, Yutaka Nakaya and Susumu Ito : Magnetic Resonance Coronary Angiography in Patients with Ischemic Heart Disease Analysis of Coronary Arterial Blood Flow Velocity Pattern, Japanese Heart Journal, Vol.41, No.2, 153-164, 2000.
(Summary)
Only a few reports evaluating coronary arterial blood flow velocity patterns using magnetic resonance (MR) coronary angiography have appeared to date. This study reports an evaluation of coronary arterial blood flow velocity patterns in patients with ischemic heart disease and in healthy subjects using MR coronary angiography. The subjects consisted of 20 patients with ischemic heart disease (IHD group) and 20 normal healthy subjects (N group). Using the fCARD PC method, ECG-gated MR coronary angiography was performed using an anteroposterior opposing phased array coil. Regions of interest were placed on bilateral coronary arteries to measure coronary arterial blood flow velocity patterns. The IHD group was divided into two subgroups, based on the presence (MI group) or absence (AP group) of infarcted myocardium using 99m Tc-methoxyisobutylisonitrile (MIBI) myocardial scintigraphy. Average diastolic peak velocity (ADPV) was lower in the IHD group than in the N group. In addition, the diastolic / systolic velocity ratio (DSVR) was significantly lower in the MI group. Moreover, in the AP group, both the ADPV and DSVR values were significantly increased in those who had undergone percutaneous transluminal coronary angioplasty postoperatively. Different from the Doppler guidewire method, MR coronary angiography facilitates noninvasive evaluation of coronary arterial blood flow velocity. Therefore, these results indicate that MR coronary angiography represents a potentially useful technique for diagnosing lesions of coronary arteries and evaluating their functions. This noninvasive method can be expected to replace the invasive Doppler guidewire method in the near future with development of MR coronary angiography technology.
Masafumi Harada, Hirokazu Miyoshi, Masaaki Uno, Toshiko Okada, Sonoka Hisaoka and Hiromu Nishitani : Neuronal impairment of adult moyamoya disease detected by quantified proton MRS and comarison with cerebral perfusion by SPECT with Tc-99m HM-PAO: A trial of clinical quantification of metabolites, Journal of Magnetic Resonance Imaging : JMRI, Vol.10, No.2, 124-129, 1999.
(Summary)
We evaluated neuronal impairment of adult moyamoya patients by proton magnetic resonance spectroscopy (MRS) and cerebral perfusion scintigraphy. After evaluating two methods for compensating relaxation times, we selected a long TR, short TE sequence to achieve better reproducibility. The cerebral blood flow (CBF) value was measured by scintigraphy following the method of quantification reported in the previous literature. N-acetyl aspartate (NAA) concentrations and CBFs value were decreased statistically (P < 0. 05) compared with those of the age-matched normal controls. However, the decreased rate of NAA concentration was changed more than the CBF value, and no linear correlation was found between the two values. We considered that the NAA concentration was not always correlated with that of the present cerebral perfusion. The NAA concentration showed a more dispersive distribution in patients than in controls, indicating a large individual variation in neuronal impairment. We concluded that proton MRS may provide useful information about neuronal impairment in individual patients. J. Magn. Reson Imaging 1999;10:124-129.
Hideki Otsuka, Masafumi Harada, K Mori, S Hisaoka and Hiromu Nishitani : Brain metabolites in the hippocampus-amygdala region and cerebellum in autism: an 1H-MR spectroscopy study., Neuroradiology, Vol.41, No.7, 517-519, 1999.
(Summary)
Histological abnormalities of the brain in autism have been investigated extensively. We studied metabolites in the hippocampus-amygdala (HA) region and cerebellum. We examined the right HA region and left cerebellar hemisphere of 27 autistic patients 2-18 years old, 21 boys and 6 girls and 10 normal children 6-14 years old, 4 boys and 6 girls, using the STEAM sequence. This sequence was used to minimise the influence of relaxation times. The N-acetyl aspartate (NAA) concentration was significantly lower (P = 0.042) in autistic patients than in normal children (9.37 and 10.95 mM, respectively). There was no significant difference in other metabolites. The correlation coefficient (r value) of NAA between the HA region and cerebellum was 0.616. The decreased NAA concentration may be due to neuronal hypofunction or immature neurons. The NAA concentration in the HA region and cerebellum may be related, because of neuronal circuits or networks.
Hideki Otsuka, Masafumi Harada, K Koga and Hiromu Nishitani : Effects of hepatic impairment on the metabolism of fructose and 5-fluorouracil, as studied in fatty liver models using in vivo 31P-MRS and 19F-MRS., Magnetic Resonance Imaging, Vol.17, No.2, 283-290, 1999.
(Summary)
The purpose of this study was to observe the effects of hepatic impairment on the metabolism of fructose and 5-fluorouracil (5-FU) in fatty liver models using in vivo 31P-MRS and 19F-MRS and to compare the results. In addition, we compared the results to those of other conventional tests such as laboratory examinations, imaging and pathology. Male SIc:Wistar rats were examined on BEM170/200 (4.7 T, Otsuka Electronics, USA) with 17-mm diameter surface coil. Fatty liver was induced by a choline deficient diet (CD diet) for 2 weeks. 31P-MRS were obtained for 90 min after intravenous (i.v.) injection of 1 g/kg of fructose and 19F-MRS were measured for 100 min after i.v. injection of 100 mg/kg of 5-FU. 1H-MRS and 1H-MRI were also performed. On 31P-MRS, there was no statistical difference in the time course of phosphomonoester (PME), adenosine triphosphate (ATP), and inorganic phosphate (Pi) between CD diet group and control group. On 19F-MRS, we detected high peak of fluoronucleotide (Fnct) and suppressed peak of alpha-fluoro-beta-alanine (FBAL) in CD diet group. We showed the metabolism of fructose and 5-FU by 31P-MRS and 19F-MRS, respectively. There was no difference in fructose metabolism but we observed increased fluoronucleotide and decreased a-fluoro-b-alanine in 5-FU metabolism of fatty liver. We speculate that the effects of hepatic impairment in fatty liver may be more severe on 5-FU metabolism and the increased fluoronucleotide may reflect cell proliferation.
(Keyword)
Animals / Antimetabolites / Choline Deficiency / Fatty Liver / Fluorouracil / Fructose / Liver / nuclear magnetic resonance spectroscopy / Male / Rats / Rats, Wistar / Time Factors
Shuji Ozaki, Masaaki Kosaka, Masafumi Harada, Hiromu Nishitani, Masaaki Odomi and Toshio Matsumoto : Radioimmunodetection of human myeloma xenografts with a monoclonal antibody directed against a plasma cell specific antigen, HM1.24, Cancer, Vol.82, No.11, 2184-2190, 1998.
(Keyword)
monoclonal antibody / multiple myeloma / F(ab')2 fragment / plasma cell / severe combined immunodeficiency mouse
Masafumi Harada, Miki Tanouchi, Kaeko Arai, Hiromu Nishitani, Hirokazu Miyoshi and Toshiaki Hashimoto : Therpeutic Efficacy of A Case of Pyruvate Dehydrogenase Complex Deficiency Monitored by Localized Proton Magnetic Resonance Imaging, Magnetic Resonance Imaging, Vol.14, No.1, 129-133, 1996.
Masafumi Harada, Miki Tanouchi, Hiromu Nishitani, Hirokazu Miyoshi, Kazuhiko Bandou and Seiji Kannuki : Non-invasive Characterization of Brain Tumor by in-vivo Proton Magnetic Resonance Spectroscopy, Japanese Journal of Cancer Research, Vol.86, 329-332, 1995.
Yoshihiro Takegawa, Kashihara Keniti, Seo Kouji, Masafumi Harada, Sasaka Kaoru and Hiroshe Chieko : Clinical trial of UFT against carcinoma of the Uterine Cervix, KARKINOS, Vol.5, No.8, 951-957, 1992.
274.
Hirokazu Miyoshi, Tomoyuki Moribe, Masafumi Harada and Hiromu Nishitani : Accuracy of the results measured by in vivo 1H-MRS using model solution, The Tokushima Journal of Experimental Medicine, Vol.39, No.1-2, 63-67, 1992.
275.
Miki Tanouchi, Osamu Sui, Kenichi Kashihara, Masafumi Harada, Toshihumi Mukaijo, Kaoru KItsukawa, Noritami Tokuyama, Ryouichi Ohtsuka, Hitoshi Ikushima, Hiromu Nishitani and Yoshihiro Takegawa : A study of skeletal metastasis of Carcinoma of the Uterine Cervix, The Official Jpurnal of The Japanese Society for Therapeutic Radiology and Oncology, Vol.02, No.02, 111-117, 1990.
Yoshihiro Takegawa, Chieko Hirose, Masafumi Harada, Yoshitami Tokuyama, Miki Tanouchi, Kaoru Kithukawa, Tetsuo Yanagawa, Hideo Yoshida and Mitsunobu Sato : Multidisciplinary treatment of carcinoma of the alveolus and gingiva, The Official Jpurnal of The Japanese Society for Therapeutic Radiology and Oncology, Vol.01, No.02, 111-118, 1989.
Academic Paper (Unrefereed Paper):
1.
Yuki Matsumoto, Koji Fujita, Masafumi Harada, Yuki Kanazawa and Miyoshi Mitsuharu : Characterization of Movement Disorders Using Multimodal Neuroimaging, European Congress of Radiology (EPOS), 2022.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa and Miyoshi Mitsuharu : Endogenous/exogenous tracers in CEST for pH measurement at 3T MRI, European Congress of Radiology (EPOS), 2022.
Yuki Matsumoto, Yuki Kanazawa, Yuki Kinjo, Masafumi Harada, Toshiaki Miyati, Hiroaki Hayashi, Mitsuharu Miyoshi, Naoki Maeda, Yasuhisa Kanematsu, Yasushi Takagi and Akihiro Haga : Evaluation of Blood Flow and Plaque Vulnerability in Carotid Artery Stenosis Focusing on Morphological and Component Characteristics, Proceedings of the 2022 ISMRM & SMRT ANNUAL MEETING & EXHIBITION, No.3783, 2022, 2022.
4.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Fukuda Nagomi, Kitano Syun, Taniguchi Yo, Ono Masaharu and Bito Yoshitaka : Brain Tumor Characterization and Assessment using Automatic Detection of Extracellular pH Change, Proceedings of the 2021 ISMRM & SMRT ANNUAL MEETING & EXHIBITION, No.3749, 2021.
5.
Hiroki Teraoku, Yuji Morine, Naoto Uyama, Tetsuya Ikemoto, Shuichi Iwahashi, Yu Saitou, Chie Takasu, Satoru Imura, Masafumi Harada and Mitsuo Shimada : Role of Central Hypo-enhancement in the Hepatic Arterial Phase of Dynamic Computed Tomography in Patients with Mass-Forming Intrahepatic Cholangiocarcinoma., World Journal of Surgery, Vol.44, No.7, 2350-2358, 2020.
(Summary)
The enhancement pattern in the hepatic arterial phase (HAP) of dynamic computed tomography (CT) is reportedly a prognostic marker in patients with intrahepatic cholangiocarcinoma (IHCC). This study was performed to clarify the significance of central hypo-enhancement in the HAP in patients with mass-forming IHCC. Forty patients who had undergone initial surgical resection for mass-forming IHCC were enrolled. The dynamic CT was scanned 40 s after contrast agent injection as the HAP. A radiologist classified the patients into three groups based on the vascular pattern: the hyper-enhancement group (Hyper group), rim-enhancement group (Rim group), and hypo-enhancement group (Hypo group). The surgical specimens were immunohistochemically stained for hypoxia-inducible factor 1 (HIF-1). The correlation with clinicopathological findings and HIF-1 expression was investigated. The Hyper, Rim, and Hypo groups comprised 8, 7, and 25 patients, respectively. There were no significant correlations between the groups and clinicopathological factors. Overall survival (OS) was significantly worse in the Hypo than in the Hyper group (p = 0.03). OS was also significantly worse in the Rim +ypo group (i.e., hypo-enhancement in the central tumor) than in the Hyper group (p = 0.04). Furthermore, inclusion in the Rim +ypo group was a prognostic factor for OS (hazard ratio 6.68). High HIF-1 expression in the central part of the tumor was correlated with central hypo-enhancement (Hyper group: 25% and Rim +ypo group: 72%). Central hypo-enhancement was a prognostic factor in patients with IHCC. The high malignant potential of tumors with central hypo-enhancement might be associated with HIF-1 upregulation.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Takashi Abe, Maki Ohtomo, Taniguchi Yo, Ono Masaharu and Bito Yoshitaka : Calculation of Concentration of Contrast Media, Relaxivity, Extracellular pH and Oxygen Extraction Fraction for Brain Tumor Characterization, Proceedings of the 28th Annual Meeting of ISMRM, No.4983, 2020.
7.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Takashi Abe, Maki Ohtomo, Taniguchi Yo, Ono Masaharu and Bito Yoshitaka : Calculation of molar relaxivity and concentration map of Gd-DTPA map using quantitative parameter map before and after injection for brain metastasis, Proceedings of the 27th Annual Meeting of ISMRM, No.4983, 2019.
8.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Takashi Abe, Maki Ohtomo and Miyoshi Mitsuharu : Chemical exchange saturation transfer imaging depending on several neurodegenerative diseases at 3T, Proceedings of the 27th Annual Meeting of ISMRM, No.2795, 2019.
9.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Maki Ohtomo, Amgalan Enkh Dolgorsuren, Ariumbold Gankhuyag, Takamatsu Shin and Yamashita Yuichi : Which number of b-value is better for accurate calculation of virtual MR elastography?, European Congress of Radiology (EPOS), C-1761, 2019.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Maki Ohtomo, Ariunbold Gankhuyag, Amgalan Enkh Dolgorsuren, Takamatsu Shin and Yamashita Yuichi : Why are shear stiffness and estimated intravoxel incoherent motion map correlated in the liver?, European Congress of Radiology (EPOS), C-1789, 2019.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Maki Ohtomo and Mitsuharu Miyoshi : Chemical exchange saturation transfer imaging for neurodegenerative diseases, Proceedings of the 26th Annual Meeting of ISMRM, No.2096, 2018.
12.
Koji Fujita, 大崎 裕亮, Takashi Abe, Masafumi Harada and 梶 隆兒 : T2*強調画像における脳実質・脳表の低信号, Practical Currently, Vol.25, No.1, 38-42, 2015.
Emiko Fujii, Kenji Mori, Masahito Miyazaki, Toshiaki Hashimoto, Masafumi Harada and Shoji Kagami : Function of the frontal lobe in autistic individuals: a proton magnetic resonance spectroscopic study, The Journal of Medical Investigation : JMI, Vol.57, No.1,2, 35-44, 2010.
(Summary)
In this investigation, we studied differences in chemical metabolites in certain brain regions between autistic patients and normal control subjects. Proton magnetic resonance spectroscopy ((1)H-MRS) was used to evaluate functional activity in these regions. Specific regions studied were right and left dorsolateral prefrontal cortex(DLPFC) and the anterior cingulated cortex(ACC). In the ACC, the N-acetylaspartate(NAA)/creatine/phosphocreatine(Cr) ratio in autistic patients (n=31) was significantly lower than that in control subjects (n=28). The decrease in the NAA/Cr ratio for the ACC was much greater in the group with worst social ability. NAA/Cr for the left DLPFC and social ability of autistic patients also correlated well. Furthermore, NAA/Cr for the left DLPFC in the group with intelligence quotient (IQ) below 50 was significantly less than in controls. NAA/Cr for the right DLPFC in autistic patients was not decreased compared to controls, and did not correlate with IQ or social ability. These findings suggest neuronal dysfunction in the ACC and left DLPFC in autism, and also a relationship between social disability and metabolic dysfunction in these regions. Dysfunction in the ACC and the left DLPFC may contribute to the pathogenesis of autism.
Hirokazu Miyoshi, Masafumi Harada, 栗本 有理, 谷 恵理奈, 益成 達也, 吉塚 彩, 下川部 力 and Hiromu Nishitani : 機能性磁気共鳴画像(FMRI)法を用いた視覚神経系の賦活に関する基礎的検討, Bulletin of School of Medical Sciences, the University of Tokushima, Vol.7, 155-159, 1997.
17.
Yoshihiro Takegawa, S. Kawano, Hirofumi Yagi, Sumiko Yoshinaga, H. Saito, Masafumi Harada, Hitoshi Ikushima, M. Takahashi and K. Sasaka : Clinical results of radiotherapy and B-M therapy for advanced cervical cancer, Bulletin of School of Medical Sciences, the University of Tokushima, Vol.7, 105-110, 1997.
18.
Hirokazu Miyoshi, 石川 弘子, 浮浦 紀子, 中川 将人, Masafumi Harada and Hiromu Nishitani : 水溶性高分子で構造化した水に溶解した代謝物質の緩和時間変化, Bulletin of School of Medical Sciences, the University of Tokushima, Vol.5, 115-119, 1995.
19.
Hirokazu Miyoshi, Masafumi Harada, 榎津 浩人, 正岡 憲治 and Hiromu Nishitani : 1H-MRSによる脳内代謝物質の内部標準としての水の有用性, Bulletin of School of Medical Sciences, the University of Tokushima, Vol.4, 229-234, 1994.
20.
Hirokazu Miyoshi, Masafumi Harada, 大霜 雄紀, 立石 貴代子 and Hiromu Nishitani : モデル溶液中の脳内代謝物質と水の緩和時間の基礎的検討, Bulletin of School of Medical Sciences, the University of Tokushima, Vol.4, 269-272, 1994.
21.
Hirokazu Miyoshi, Masafumi Harada, 川添 絵美 and Hiromu Nishitani : 脳運動野における機能性MRIの基礎的検討, Bulletin of School of Medical Sciences, the University of Tokushima, Vol.4, 273-275, 1994.
22.
竹本 幸志, Hirokazu Miyoshi, Masafumi Harada and Hiromu Nishitani : 1H-MRスペクトロスコピーによる脳内代謝物質の検討, Bulletin of School of Medical Sciences, the University of Tokushima, Vol.3, 177-182, 1993.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : 特集【Step up MRI 2024 最前線を行く:MRI研究の最新動向と臨床応用】III 各領域における最新MRI技術の臨床応用. 8.骨盤 MRI の最前線 ─ 婦人科疾患を中心に, インナービジョン, Vol.39, No.9, 53-57, Aug. 2024.
2.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : 【画像検査を使いこなす —放射線科医からの贈り物】第Ⅲ部 各疾患の画像診断 9 泌尿生殖器 子宮腫瘍, The Journal of the Japan Medical Association, Vol.153, No.S1, 305-306, Jun. 2024.
3.
岡田 直子, Shoichiro Takao and Masafumi Harada : 腫瘍随伴症候群, The Journal of the Japan Medical Association, Vol.153, S337,S340, Jun. 2024.
4.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : 【非典型症例と類似疾患を知ってCommon Diseaseを極める】3. 腹部 18. 女性生殖器 子宮, Japanese Journal of Clinical Radiology, Vol.68, No.12, 1279-1294, Dec. 2023.
5.
松下 知樹, Masafumi Harada and Shoichiro Takao : Morel-Lavallee lesion of the knee, Clinical Imagiology, Vol.39, No.10, 1118-1125, Oct. 2023.
6.
平岡 淳一郎, Shoichiro Takao and Masafumi Harada : 膝関節の骨壊死, Japanese Journal of Clinical Radiology, Vol.68, No.8, 765,771, Aug. 2023.
7.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : 【子宮内膜症の病態と画像診断 ー温故知新】子宮内膜症の診断に有用なadvanced MR techniques, Japanese Journal of Imaging Diagnosis, Vol.43, No.8, 797-804, Jun. 2023.
Yuki Kanazawa and Masafumi Harada : Editorial for "Chemical Exchange Saturation Transfer (CEST) MRI for Differentiating Radiation Necrosis from Tumor Progression in Brain Metastasis: Application in a Clinical Setting", Journal of Magnetic Resonance Imaging : JMRI, Vol.Epub ahead of print, Oct. 2022.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : 【妊孕性・機能温存のための画像診断-Keep the QOL of Women-】妊孕性・機能温存治療のためのadvanced MR techniques, Japanese Journal of Imaging Diagnosis, Vol.41, No.10, 1131-1138, Aug. 2021.
足立 克仁, Takashi Iwase, Masashi Akaike, 斎藤 美穂, 柏木 節子, 橋口 修二, Masataka Sata, Shoichiro Takao, Masafumi Harada and 川井 尚臣 : Late Gadolinium Enhancement of Cardiac Magnetic Resonance and Computed Tomography of Skeletal Muscle at Lower Legs in Female Carriers of Duchenne Muscular Dystrophy, Japanese Journal of National Medical Services, Vol.67, No.2, 63-69, Feb. 2013.
Stroke Care Unit(SCU)in Tokushima University Hospital has been opened since November1999. Patients with acute stroke in SCU were diagnosed by stroke MRI and biomarker immediatelyafter their admission. Diffusion MRI could diagnose the ultra-acute ischemic and hemorrhagiclesion except brainstem ischemic lesion within3hrs after onset. Diffusion-Perfusion mismatchwas useful to indicate intra-arterial thrombolytic therapy. 3T-MRI was introduced since March2004，and it can measured functional MR spectroscopy and tractography more quickly compared to1．5T-MRI.Plasma oxidized LDL in patients with acute cerebral infarction was significantly higher than thatin healthy control and it became peak level during3‐5day after stroke onset.In conclusion, stroke MRI and plasma oxidized LDL are useful diagnostic tools for acute stroke.
Mayuka Seguchi, Yuki Kanazawa, Tosiaki Miyati, Masafumi Harada, Mitsuharu Miyoshi, Hiroaki Hayashi and Akihiro Haga : How Can We Measure Biological Viscosity Non-Invasively Using MRI?, RSNA2024 (the 110th Scientific Assembly and Annual Meeting of the Radiological Society of North America), Chicago, Dec. 2024.
2.
Ohshiro Ryuji, Yuki Kanazawa, Akihiro Haga and Masafumi Harada : How Do We Determine the Water Volume in the Central Nervous System?, RSNA2024 (the 110th Scientific Assembly and AnnualMeeting of the Radiological Society of North America), Chicago, Dec. 2024.
3.
Yuki Kanazawa, Yo Taniguchi, Masafumi Harada, Kosuke Ito and Yoshitaka Bito : Visualization of Human Brain Cortical Layers Using Quantitative Parameter Mapping on a 3 Tesla Scanner, The 33st Annual Meeting of ISMRM, Singapore, May 2024.
4.
Ohshiro Ryuji, Yuki Kanazawa, Akihiro Haga and Masafumi Harada : Development of numerical phantom converting from electron microscopic analysis to multi-component water fraction for MRI simulator., The 33st Annual Meeting of ISMRM, Singapore, May 2024.
5.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : A comprehensive review of adnexal lesions with preserved/enlarged ovarian follicles: Wide spectrum of clinical and imaging manifestations, differential diagnosis and pitfalls, ECR2023, Wien, Mar. 2024.
6.
Shunsuke Uotani, Yuki Kanazawa, Taniguchi Yo, Ito Kosuke, Bito Yoshitaka, Yuki Matsumoto, Masafumi Harada and Akihiro Haga : Determining Imaging Parameters of a Gradient-echo Technique for Myelin Water Fraction., European Congress of RadiologyECR2024, Wien, Mar. 2024.
7.
Yuki Matsumoto, Shotaro Haji, Masafumi Harada, Wataru Sako, Yuki Kanazawa, Yuishin Izumi, Taniguchi Yo, Ono Masaharu and Bito Yoshitaka : Quantitative Parameter Mapping of Brain Structure and Components in Parkinsons Disease and Progressive Supranuclear Palsy, RSNA2023 (Radiological Society of North America), Chicago, Nov. 2023.
8.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Endometriosis Revisited: Current Concept of Pathophysiology, Diagnosis, and Therapeutic Strategy, RSNA2023, Chicago, Nov. 2023.
9.
Yuki Kanazawa, Tosiaki Miyati, Masafumi Harada, Mitsuharu Miyoshi, Mayuka Seguchi, Hiroaki Hayashi, Yuki Matsumoto, Yasuhisa Kanematsu and Yasushi Takagi : Metabolic Analysis Within an Atherosclerotic Plaque Using Chemical Exchange Saturation Transfer Imaging, The 109th Scientific Assembly and Annual Meeting of the Radiological Society of North America (RSNA2023), Chicago, Nov. 2023.
10.
Takashi Kawanaka, Akiko Kubo, Chisato Tonoiso, Hitoshi Ikushima, Masafumi Harada and Kawanaka Taeko : Initial Experience and Evaluation of Safety in Hypofractionated Accelerated Partial Breast irradiation using a Brachytherapy Multi-catheter Approach, FARO & KOSRO 2023, Seul, Korea, Oct. 2023.
11.
Kanon Monda, Hitoshi Ikushima, Yuki Matsumoto, Motoharu Sasaki, Michihito Shimokawa and Masafumi Harada : Proposal of a rigid registration method for contrast-enhanced MRI and C-11 methionine PET using iterative closest point and convolutional Neural Network, ISMRM JPC2023, The 8th Annual Scientific Meeting of the ISMRM Japanese Chapter, Sep. 2023.
12.
Kyohei Maekawa, Satoru Kohno, Yuki Matsumoto, Masafumi Harada and Koji Fujita : Imaging biomarker in Prodromal Parkinson's disease using a novel network index of resting state fMRI, 29th Annual Meeting of The Organization for Human Brain Mapping,Montréal, Canada, Jul. 2023.
Yuki Kanazawa, KITANO Shun, Masafumi Harada, Yo Taniguchi, Yuki Matsumoto, Hiroaki Hayashi, Kosuke Ito, Yoshitaka Bito and Akihiro Haga : Myelin Water Atlas Template Derived from Quantitative Parameter Mapping, The 32st Annual Meeting of ISMRM, Toronto, Jun. 2023.
14.
Yuki Kanazawa, Tosiaki Miyati, Masafumi Harada, Mitsuharu Miyoshi, Yuki Matsumoto, Hiroaki Hayashi, Yasuhisa Kanematsu and Yasushi Takagi : Evaluation of Biological Metabolic Activity within an Atherosclerotic Plaque using Chemical Exchange Saturation Transfer Imaging, The 32st Annual Meeting of ISMRM, Toronto, Jun. 2023.
15.
Mayuka Seguchi, Yuki Kanazawa, Tosiaki Miyati, Masafumi Harada, Mitsuharu Miyoshi, Yuki Matsumoto, Hiroaki Hayashi, Yasuhisa Kanematsu and Yasushi Takagi : Diffusion weighted-viscosity imaging for atherosclerotic plaques, The 32st Annual Meeting of ISMRM, Toronto, Jun. 2023.
16.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Malignant Transformation of Benign Gynecologic Diseases: Wide Spectrum of Clinical and Imaging Manifestations, Differential Diagnosis and Pitfalls, ECR2022, Wien, Mar. 2023.
17.
Takayoshi Shinya, Matsushita Tomoki, Mitsuhashi Ryota, Saya Matsuzaki, Onishi Hajime, Yuka Hiroshima, Youichi Otomi, Michiko Kubo and Masafumi Harada : Usefulness of F-18 FDG PET/CT imaging in Hepatic Lesions, 13th Congress of the World Federation of Nuclear Medicine and Biology, Sep. 2022.
18.
Nagomi Fukuda, Yuki Kanazawa, Hiroaki Hayashi, Yuki Matsumoto, Masafumi Harada, Motoharu Sasaki and Akihiro Haga : Development of a B1 correction method without additional scanning VFA T1 map., European Congress of Radiology, Wien, Jul. 2022.
19.
Yuki Matsumoto, Yuki Kanazawa, Yuki Kinjo, Masafumi Harada, Toshiaki Miyati, Hiroaki Hayashi, Mitsuharu Miyoshi, Naoki Maeda, Yasuhisa Kanematsu, Yasushi Takagi and Akihiro Haga : Evaluation of Blood Flow and Plaque Vulnerability in Carotid Artery Stenosis Focusing on Morphological and Component Characteristics, ISMRM 30th Annual Meeting, London, May 2022.
20.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Susceptibility-weighted MR sequence for the evaluation of intra-tumoral hemorrhage: Differentiation of benign and malignant ovarian tumors, ISMRM2022, London, May 2022.
21.
Mayumi Takeuchi, Kenji Matsuzaki, Yoshimi Bando and Masafumi Harada : Dynamic contrast-enhanced magnetic resonance imaging of endometrial cancer with/without squamous differentiation, ISMRM2022, London, May 2022.
22.
Yuki Kanazawa, Masafumi Harada, Mitsuharu Miyoshi and Yuki Matsumoto : Evaluation of brain tumor and surrounding tissue activity using multi-pool CEST imaging on 3 Tesla scanner, Joint Annual Meeting ISMRM-ESMRMB & ISMRT 31st Annual Meeting, London, May 2022.
23.
Nagomi Fukuda, Yuki Kanazawa, Hiroaki Hayashi, Yuki Matsumoto, Masafumi Harada, Motoharu Sasaki and Akihiro Haga : Development of self-calibrating B1 correction for three-dimensional variable flip angle T1 mapping, Joint Annual Meeting ISMRM-ESMRMB & ISMRT 31st Annual Meeting, London, May 2022.
24.
Shun Kitano, Yuki Kanazawa, Masafumi Harada, Yo Taniguchi, Yuki Matsumoto, Hiroaki Hayashi, Kosuke Ito, Yoshitaka Bito and Akihiro Haga : Conversion map from quantitative parameter mapping to myelin water fraction, Joint Annual Meeting ISMRM-ESMRMB & ISMRT 31st Annual Meeting, London, May 2022.
25.
Natsuki Ikemitsu, Yuki Kanazawa, Akihiro Haga, Hiroaki Hayashi, Yuki Matsumoto and Masafumi Harada : Determination of Alzheimer's disease based on morphology and atrophy using machine learning combined with automated segmentation., Joint Annual Meeting ISMRM-ESMRMB & ISMRT 31st Annual Meeting, London, May 2022.
26.
Fukuda Nagomi, Yuki Kanazawa, Hiroaki Hayashi, Yuki Matsumoto, Masafumi Harada, Motoharu Sasaki and Akihiro Haga : Variable flip angle T1 mapping without acquiring data for B1 correction, Joint International Conference on Radiological Physics and Technology, Yokohama, Apr. 2022.
27.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Diagnostic impact of computed DWI combined with reduced FOV DWI for gynecological diseases., ECR2022, Wien, Mar. 2022.
28.
Natsuki Ikemitsu, Yuki Kanazawa, Masafumi Harada, Yuki Matsumoto, Hiroaki Hayashi, Kosuke Ito, Yo Taniguchi, Yoshitaka Bito and Akihiro Haga : Determination of white matter structure index for voxel basedmorphometry and connectivity analysis., European Congress of Radiology, Wien, Mar. 2022.
29.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa and Miyoshi Mitsuharu : Endogenous/exogenous tracers in CEST for pH measurement at 3T MRI, European Congress of Radiology, Wien, Mar. 2022.
30.
Yuki Matsumoto, Koji Fujita, Masafumi Harada, Yuki Kanazawa and Miyoshi Mitsuharu : Characterization of Movement Disorders Using Multimodal Neuroimaging, European Congress of Radiology, Wien, Mar. 2022.
31.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Yo Taniguchi, Masaharu Ono and Yoshitaka Bito : What Is The Extracellular pH Of Brain Tumors And How Can We Detect Brain Tumors Using Gadolinium-based-contrast Agents?, RSNA2021 (Radiological Society of North America), Chicago, Nov. 2021.
32.
Naoki Maeda, Yuki Kanazawa, Yuki Kinjo, Yuki Matsumoto, Masafumi Harada, Tosiaki Miyati, Hiroaki Hayashi, Mitsuharu Miyoshi, Yasuhisa Kanematsu, Yasushi Takagi and Akihiro Haga : Is it possible to evaluate morphological carotid artery stenosis information using NASCET criteria?, RSNA2021 (Radiological Society of North America), Chicago, Nov. 2021.
33.
Shotaro Haji, R Oki, Koji Fujita, Yusuke Osaki, S Nagano, N Atsuta, Y Kanazawa, Y Matsumoto, A Arisawa, H Kawai, Y Sato, S Sakaguchi, K Yaki, T Hamatani, Hiroaki Yanagawa, Masafumi Harada, G Sobue and Yuishin Izumi : EPI-589 early phase 2 investigator-initiated clinical trial for ALS (EPIC-ALS): protocol for an exploratory study, Pan-Asia Consortium for Treatment and Research in ALS (PACTALS) 2021 NAGOYA, Nagoya, Sep. 2021.
34.
Satoru Kohno, Daisuke Sato, Sumida Nami, Yuki Matsumoto, Masafumi Harada and Koji Fujita : Radial Correlation and Radial Similarity Contrast Reveal Abnormal Brain Networks in Dystonia, 27th Annual Meeting of The Organization for Human Brain Mapping, web conference, Jun. 2021.
35.
Yoshiteru Tada, Toshitaka Fujihara, Kenji Shimada, Nobuaki Yamamoto, Hiroki Yamazaki, Yuishin Izumi, Masafumi Harada, Yasuhisa Kanematsu and Yasushi Takagi : Peri-ictal normal arterial spin labeling imaging in patients with seizures, 13 回アジア・オセアニアてんかん学会(13th AOEC), Jun. 2021.
36.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Uterine cervical adenocarcinomas associated with lobular endocervical glandular hyperplasia: MR imaging manifestations, ISMRM2021, Vancouver, May 2021.
37.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : The feasibility of reduced field-of-view DWI in evaluating bladder invasion of uterine cervical cancery, ISMRM2021, Vancouver, May 2021.
38.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Yo Taniguchi, Masaharu Ono and Yoshitaka Bito : Brain Tumor Characterization and Assessment using Automatic Detection of Extracellular pH Change, ISMRM 29th Annual Meeting, Online meeting, May 2021.
39.
Naoki Maeda, Yuki Kanazawa, Masafumi Harada, Yo Taniguchi, Yuki Matsumoto, Hiroaki Hayashi, Kosuke Ito, Yoshitaka Bito and Akihiro Haga : Derivation of Water Exchange Constants between Components using Quantitative Parameter Mapping (QPM), ISMRM 29th Annual Meeting, Online, May 2021.
40.
Yuki Kanazawa, Masafumi Harada, Yo Taniguchi, Syun Kitano, Nagomi Fukuda, Yuki Matsumoto, Hiroaki Hayashi, Kosuke Ito, Yoshitaka Bito and Akihiro Haga : Myelin imaging derived quantitative parameter mapping compared to myelin water fraction, ISMRM 29th Annual Meeting, Online, May 2021.
41.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Role of advanced MR imaging for minimally invasive treatments in patients with gynecological diseases, ECR2021, Wien, Mar. 2021.
42.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Can MRI Differentiate Uterine Sarcomas from Leiomyomas?, RSNA2020, Chicago, Nov. 2020.
43.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Clinical Impact of Computed Diffusion-Weighted MR Imaging in the Female Pelvis., RSNA2020, Chicago, Nov. 2020.
44.
Yuki Matsumoto, Masafumi Harada, Yuki Kanazawa, Takashi Abe, Maki Ohtomo, Taniguchi Yo, Ono Masaharu and Bito Yoshitaka : Calculation of Concentration of Contrast Media, Relaxivity, Extracellular pH and Oxygen Extraction Fraction for Brain Tumor Characterization, ISMRM 28th Annual Meeting, Paris, Aug. 2020.
45.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : MRI findings of uterine adenomatoid tumors including diffusion-weighted imaging with pathologic correlation, ISMRM2020, Sydney, Aug. 2020.
46.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Clinical value of N-acetyl mucinous compounds and lipid peaks in differentiating benign and malignant ovarian mucinous tumors by MR spectroscopy, ISMRM2020, Sydney, Aug. 2020.
47.
Yuki Kanazawa, Masafumi Harada, Mitsuharu Miyoshi, Takashi Abe, Yuki Matsumoto and Yasushi Takagi : Characterization of Brain Tumors using Amide Proton and Nuclear Overhauser Effect at 3 Tesla MR Scanner, ISMRM Virtual Conference, Aug. 2020.
48.
Yuki Kanazawa, Masafumi Harada, Tosiaki Miyati, Takashi Abe, Mitsuharu Miyoshi, Yuki Matsumoto, Hiroaki Hayashi, Yasuhisa Kanematsu and Yasushi Takagi : Chemical Exchange Saturation Transfer Imaging for Atherosclerotic Plaques, ISMRM Virtual Conference, Aug. 2020.
49.
Mayumi Takeuchi, Kenji Matsuzaki and Masafumi Harada : Tissue characterization in gynecologic diseases by means of advanced MR imaging: Comprehensive diagnostic strategy for tumors and tumor-like lesions in the female pelvis, ECR2020, Wien, Jul. 2020.