2018年12月, 北米放射線学会, Cum Laude　　　　　　　　　　　　　　　
Imaging Findings in Medication-Induced Changes of the Central Nervous System: What Radiologists Should Know
原田 太以佑

2018年09月, 第46回日本磁気共鳴医学会大会, 大会長賞　　　　　　　　　　　　　　　
Phase I study of 17 O-labeled water: safety and feasibility study of indirect proton MRI for the evaluation of cerebral blood flow
原田 太以佑

2016年02月, 日本磁気共鳴医学会, Travel award　　　　　　　　　　　　　　　
原田 太以佑

Intracerebral transplantation of MRI-trackable autologous bone marrow stromal cells for patients with subacute ischemic stroke.
Masahito Kawabori, Satoshi Kuroda, Hideo Shichinohe, Kaoru Kahata, Souichi Shiratori, Satoshi Ikeda, Taisuke Harada, Kenji Hirata, Khin Khin Tha, Masato Aragaki, Shunsuke Terasaka, Yoichi M Ito, Naoki Nishimoto, Shunsuke Ohnishi, Ichiro Yabe, Kohsuke Kudo, Kiyohiro Houkin, Miki Fujimura
Med (New York, N.Y.), 2024年03月18日, ［国際誌］
英語, 研究論文（学術雑誌）, BACKGROUND: Ischemic stroke is one of the leading causes of death and neurological disability worldwide, and stem cell therapy is highly expected to reverse the sequelae. This phase 1/2, first-in-human study evaluated the safety, feasibility, and monitoring of an intracerebral-transplanted magnetic resonance imaging (MRI)-trackable autologous bone marrow stromal cell (HUNS001-01) for patients with subacute ischemic stroke. METHODS: The study included adults with severe disability due to ischemic stroke. HUNS001-01 cultured with human platelet lysates and labeled with superparamagnetic iron oxide was stereotactically transplanted into the peri-infarct area 47-64 days after ischemic stroke onset (dose: 2 or 5 × 107 cells). Neurological and radiographic evaluations were performed throughout 1 year after cell transplantation. The trial was registered at UMIN Clinical Trial Registry (number UMIN000026130). FINDINGS: All seven patients who met the inclusion criteria successfully achieved cell expansion, underwent intracerebral transplantation, and completed 1 year of follow-up. No product-related adverse events were observed. The median National Institutes of Health Stroke Scale and modified Rankin scale scores before transplantation were 13 and 4, which showed improvements of 1-8 and 0-2, respectively. Cell tracking proved that the engrafted cells migrated toward the infarction border area 1-6 months after transplantation, and the quantitative susceptibility mapping revealed that cell signals at the migrated area constantly increased throughout the follow-up period up to 34% of that of the initial transplanted site. CONCLUSIONS: Intracerebral transplantation of HUNS001-01 was safe and well tolerated. Cell tracking shed light on the therapeutic mechanisms of intracerebral transplantation. FUNDING: This work was supported by the Japan Agency for Medical Research and Development (AMED; JP17bk0104045 and JP20bk0104011).

MELASに類似した脳卒中様発作を生じた神経核内封入体病の1例　　　　　　　　　　　　　　　
亀田 浩之, 原田 太以佑, 藤間 憲幸, 清水 幸衣, 池辺 洋平, 平田 健司, 矢部 一郎, 工藤 與亮
北海道放射線医学雑誌, 4, 20, 24, (NPO)メディカルイメージラボ, 2024年03月
日本語, 症例は70歳代女性。約5年前に脳炎・脳症症状のため受診し、皮膚・直腸生検にて神経核内封入体病と診断された。今回、左上下肢麻痺で当院救急搬送となった。入院時の頭部MRIでは、拡散強調画像で右頭頂後頭葉から側頭葉の皮質下白質に高信号が出現した。MRAでは右中・後大脳動脈に拡張所見を認めた。ASLと脳血流IMP-SPECTでは、右頭頂後頭葉から側頭葉にかけて広範な過灌流を認め、造影MRIでは同領域の皮質に沿った増強効果を認めた。痙攣後脳症とNIIDに伴うMELAS様の急性脳症が鑑別疾患に挙がったが、拡散強調像での皮髄境界優位の分布と大脳皮質の増強効果、ステロイドパルス療法後の臨床症状や画像所見の経過から、MELAS様の急性脳症を呈したNIIDと診断した。NIIDの症状は多彩であるが、一部の患者でMELASに類似した臨床症状と画像所見を示す症例が近年報告されており、NIID患者の脳卒中様の発症様式とその画像所見の特徴を知っておく必要がある。(著者抄録)

Improved image quality in contrast-enhanced 3D-T1 weighted sequence by compressed sensing-based deep-learning reconstruction for the evaluation of head and neck.
Noriyuki Fujima, Junichi Nakagawa, Yohei Ikebe, Hiroyuki Kameda, Taisuke Harada, Yukie Shimizu, Nayuta Tsushima, Satoshi Kano, Akihiro Homma, Jihun Kwon, Masami Yoneyama, Kohsuke Kudo
Magnetic resonance imaging, 108, 111, 115, 2024年02月09日, ［国際誌］
英語, 研究論文（学術雑誌）, PURPOSE: To assess the utility of deep learning (DL)-based image reconstruction with the combination of compressed sensing (CS) denoising cycle by comparing images reconstructed by conventional CS-based method without DL in fat-suppressed (Fs)-contrast enhanced (CE) three-dimensional (3D) T1-weighted images (T1WIs) of the head and neck. MATERIALS AND METHODS: We retrospectively analyzed the cases of 39 patients who had undergone head and neck Fs-CE 3D T1WI applying reconstructions based on conventional CS and CS augmented by DL, respectively. In the qualitative assessment, we evaluated overall image quality, visualization of anatomical structures, degree of artifacts, lesion conspicuity, and lesion edge sharpness based on a five-point system. In the quantitative assessment, we calculated the signal-to-noise ratios (SNRs) of the lesion and the posterior neck muscle and the contrast-to-noise ratio (CNR) between the lesion and the adjacent muscle. RESULTS: For all items of the qualitative analysis, significantly higher scores were awarded to images with DL-based reconstruction (p < 0.001). In the quantitative analysis, DL-based reconstruction resulted in significantly higher values for both the SNR of lesions (p < 0.001) and posterior neck muscles (p < 0.001). Significantly higher CNRs were also observed in images with DL-based reconstruction (p < 0.001). CONCLUSION: DL-based image reconstruction integrating into the CS-based denoising cycle offered superior image quality compared to the conventional CS method. This technique will be useful for the assessment of patients with head and neck disease.

内耳に造影効果を認めたCogan症候群の1例　　　　　　　　　　　　　　　
小市 裕太, 池辺 洋平, 藤間 憲幸, 亀田 浩之, 原田 太以佑, 清水 幸衣, 工藤 與亮, 竹崎 俊一郎, 藤原 圭志
Japanese Journal of Radiology, 42, Suppl., 4, 4, (公社)日本医学放射線学会, 2024年02月
日本語

Diagnosis of skull-base invasion by nasopharyngeal tumors on CT with a deep-learning approach.
Junichi Nakagawa, Noriyuki Fujima, Kenji Hirata, Taisuke Harada, Naoto Wakabayashi, Yuki Takano, Akihiro Homma, Satoshi Kano, Kazuyuki Minowa, Kohsuke Kudo
Japanese journal of radiology, 2024年01月27日, ［国内誌］
英語, 研究論文（学術雑誌）, PURPOSE: To develop a convolutional neural network (CNN) model to diagnose skull-base invasion by nasopharyngeal malignancies in CT images and evaluate the model's diagnostic performance. MATERIALS AND METHODS: We divided 100 malignant nasopharyngeal tumor lesions into a training (n = 70) and a test (n = 30) dataset. Two head/neck radiologists reviewed CT and MRI images and determined the positive/negative skull-base invasion status of each case (training dataset: 29 invasion-positive and 41 invasion-negative; test dataset: 13 invasion-positive and 17 invasion-negative). Preprocessing involved extracting continuous slices of the nasopharynx and clivus. The preprocessed training dataset was used for transfer learning with Residual Neural Networks 50 to create a diagnostic CNN model, which was then tested on the preprocessed test dataset to determine the invasion status and model performance. Original CT images from the test dataset were reviewed by a radiologist with extensive head/neck imaging experience (senior reader: SR) and another less-experienced radiologist (junior reader: JR). Gradient-weighted class activation maps (Grad-CAMs) were created to visualize the explainability of the invasion status classification. RESULTS: The CNN model's diagnostic accuracy was 0.973, significantly higher than those of the two radiologists (SR: 0.838; JR: 0.595). Receiver operating characteristic curve analysis gave an area under the curve of 0.953 for the CNN model (versus 0.832 and 0.617 for SR and JR; both p < 0.05). The Grad-CAMs suggested that the invasion-negative cases were present predominantly in bone marrow, while the invasion-positive cases exhibited osteosclerosis and nasopharyngeal masses. CONCLUSIONS: This CNN technique would be useful for CT-based diagnosis of skull-base invasion by nasopharyngeal malignancies.

Automated Detection of Cerebral Microbleeds on Two-dimensional Gradient-recalled Echo T2* Weighted Images Using a Morphology Filter Bank and Convolutional Neural Network
Noriko Nishioka, Yukie Shimizu, Toru Shirai, Hisaaki Ochi, Yoshitaka Bito, Kiichi Watanabe, Hiroyuki Kameda, Taisuke Harada, Kohsuke Kudo
Magnetic Resonance in Medical Sciences, Japanese Society for Magnetic Resonance in Medicine, 2024年
研究論文（学術雑誌）

Magnetic Resonance Water Tracer Imaging Using 17 O-Labeled Water.
Hiroyuki Kameda, Naoya Kinota, Daisuke Kato, Takaaki Fujii, Taisuke Harada, Yuji Komaki, Hiroyuki Sugimori, Tomohiro Onodera, Moyoko Tomiyasu, Takayuki Obata, Kohsuke Kudo
Investigative radiology, 59, 1, 92, 103, 2024年01月01日, ［国際誌］
英語, 研究論文（学術雑誌）, Magnetic resonance imaging (MRI) is a crucial imaging technique for visualizing water in living organisms. Besides proton MRI, which is widely available and enables direct visualization of intrinsic water distribution and dynamics in various environments, MR-WTI (MR water tracer imaging) using 17 O-labeled water has been developed, benefiting from the many advancements in MRI software and hardware that have substantially improved the signal-to-noise ratio and made possible faster imaging. This cutting-edge technique allows the generation of novel and valuable images for clinical use. This review elucidates the studies related to MRI water tracer techniques centered around 17 O-labeled water, explaining the fundamental principles of imaging and providing clinical application examples. Anticipating continued progress in studies involving isotope-labeled water, this review is expected to contribute to elucidating the pathophysiology of various diseases related to water dynamics abnormalities and establishing novel imaging diagnostic methods for associated diseases.

Improvement of image quality in diffusion-weighted imaging with model-based deep learning reconstruction for evaluations of the head and neck.
Noriyuki Fujima, Junichi Nakagawa, Hiroyuki Kameda, Yohei Ikebe, Taisuke Harada, Yukie Shimizu, Nayuta Tsushima, Satoshi Kano, Akihiro Homma, Jihun Kwon, Masami Yoneyama, Kohsuke Kudo
Magma (New York, N.Y.), 2023年11月21日, ［国際誌］
英語, 研究論文（学術雑誌）, OBJECTIVES: To investigate the utility of deep learning (DL)-based image reconstruction using a model-based approach in head and neck diffusion-weighted imaging (DWI). MATERIALS AND METHODS: We retrospectively analyzed the cases of 41 patients who underwent head/neck DWI. The DWI in 25 patients demonstrated an untreated lesion. We performed qualitative and quantitative assessments in the DWI analyses with both deep learning (DL)- and conventional parallel imaging (PI)-based reconstructions. For the qualitative assessment, we visually evaluated the overall image quality, soft tissue conspicuity, degree of artifact(s), and lesion conspicuity based on a five-point system. In the quantitative assessment, we measured the signal-to-noise ratio (SNR) of the bilateral parotid glands, submandibular gland, the posterior muscle, and the lesion. We then calculated the contrast-to-noise ratio (CNR) between the lesion and the adjacent muscle. RESULTS: Significant differences were observed in the qualitative analysis between the DWI with PI-based and DL-based reconstructions for all of the evaluation items (p < 0.001). In the quantitative analysis, significant differences in the SNR and CNR between the DWI with PI-based and DL-based reconstructions were observed for all of the evaluation items (p = 0.002 ~ p < 0.001). DISCUSSION: DL-based image reconstruction with the model-based technique effectively provided sufficient image quality in head/neck DWI.

MR vessel-encoded arterial spin labeling with the placement of metallic items to visualize the territorial blood flow after extracranial-intracranial bypass surgery: a proof-of-concept study.
Tetsuji Hayashi, Noriyuki Fujima, Taisuke Harada, Akiyoshi Hamaguchi, Shuichi Kodera
Acta radiologica (Stockholm, Sweden : 1987), 64, 5, 2841851221151144, 2841851221151144, 2023年01月12日, ［国際誌］
英語, 研究論文（学術雑誌）, BACKGROUND: Depiction of bypass blood flow in patients who received extracranial-intracranial (EC-IC) bypass surgery is important for patient care. PURPOSE: To develop a vessel-encoded arterial spin labeling (VE-ASL) method using surgical staples as a magnetic resonance (MR)-conditional product in patients who received EC-IC bypass surgery. MATERIAL AND METHODS: Pseudo-continuous labeling was used for VE-ASL acquisition with a 3-T MR unit. First, an experimental study was conducted to determine the appropriate number of surgical staples to obtain a spatially sufficient saturation effect. Thereafter, four healthy normal volunteers underwent a VE-ASL study to confirm the sufficiency of the saturation effect to the right or left common carotid artery. Finally, VE-ASL scanning was performed in seven patients after EC-IC bypass surgery to confirm the ability of VE-ASL to visualize the territorial bypass perfusion. All qualitative evaluation was performed by two neuroradiologists using a 3-point grading system (2 = good, 1 = moderate, 0 = poor). RESULTS: A quantity of 200 staples was found to be appropriate for VE-ASL scanning. In healthy volunteers, one neuroradiologist rated the images of all four cases as good, while the other rated three cases as good and one case as moderate. For the seven patients after EC-IC bypass surgery, one neuroradiologist rated all seven cases as good, and the other rated six cases as good and one case as moderate. CONCLUSION: VE-ASL using surgical staples might be useful for the evaluation of territorial bypass perfusion in patients after EC-IC bypass surgery.

長期経過を追った成人発症アレキサンダー病の1例　　　　　　　　　　　　　　　
大嶌 祐貴, 岩田 育子, 佐藤 翔紀, 石川 楓, 山田 一貴, 田中 大貴, 上床 尚, 白井 慎一, 松島 理明, 原田 太以佑, 矢口 裕章, 矢部 一郎
臨床神経学, 62, 12, 977, 977, (一社)日本神経学会, 2022年12月
日本語

長期経過を追った成人発症アレキサンダー病の1例　　　　　　　　　　　　　　　
大嶌 祐貴, 岩田 育子, 佐藤 翔紀, 石川 楓, 山田 一貴, 田中 大貴, 上床 尚, 白井 慎一, 松島 理明, 原田 太以佑, 矢口 裕章, 矢部 一郎
臨床神経学, 62, 12, 977, 977, (一社)日本神経学会, 2022年12月
日本語

Percutaneous Drainage for Postoperative Fluid Collection after Hepatobiliary Pancreatic Surgery.
Ryo Morita, Daisuke Abo, Taisuke Harada, Takeshi Soyama, Bunya Takahashi, Yuki Yoshino, Naoya Kinota, Taichi Yasui, Kohsuke Kudo
Radiographics : a review publication of the Radiological Society of North America, Inc, 42, 6, E171-E172, 2022年10月, ［国際誌］
英語, 研究論文（学術雑誌）

Utility of the deep learning technique for the diagnosis of orbital invasion on CT in patients with a nasal or sinonasal tumor.
Junichi Nakagawa, Noriyuki Fujima, Kenji Hirata, Minghui Tang, Satonori Tsuneta, Jun Suzuki, Taisuke Harada, Yohei Ikebe, Akihiro Homma, Satoshi Kano, Kazuyuki Minowa, Kohsuke Kudo
Cancer imaging : the official publication of the International Cancer Imaging Society, 22, 1, 52, 52, 2022年09月22日, ［国際誌］
英語, 研究論文（学術雑誌）, BACKGROUND: In nasal or sinonasal tumors, orbital invasion beyond periorbita by the tumor is one of the important criteria in the selection of the surgical procedure. We investigated the usefulness of the convolutional neural network (CNN)-based deep learning technique for the diagnosis of orbital invasion, using computed tomography (CT) images. METHODS: A total of 168 lesions with malignant nasal or sinonasal tumors were divided into a training dataset (n = 119) and a test dataset (n = 49). The final diagnosis (invasion-positive or -negative) was determined by experienced radiologists who carefully reviewed all of the CT images. In a CNN-based deep learning analysis, a slice of the square target region that included the orbital bone wall was extracted and fed into a deep-learning training session to create a diagnostic model using transfer learning with the Visual Geometry Group 16 (VGG16) model. The test dataset was subsequently tested in CNN-based diagnostic models and by two other radiologists who were not specialized in head and neck radiology. At approx. 2 months after the first reading session, two radiologists again reviewed all of the images in the test dataset, referring to the diagnoses provided by the trained CNN-based diagnostic model. RESULTS: The diagnostic accuracy was 0.92 by the CNN-based diagnostic models, whereas the diagnostic accuracies by the two radiologists at the first reading session were 0.49 and 0.45, respectively. In the second reading session by two radiologists (diagnosing with the assistance by the CNN-based diagnostic model), marked elevations of the diagnostic accuracy were observed (0.94 and 1.00, respectively). CONCLUSION: The CNN-based deep learning technique can be a useful support tool in assessing the presence of orbital invasion on CT images, especially for non-specialized radiologists.

Long-term consequences of residual lesions after chemoradiotherapy in patients with germinoma at onset.
Shigeru Yamaguchi, Michinari Okamoto, Yukitomo Ishi, Ryosuke Sawaya, Hiroaki Motegi, Minako Sugiyama, Taisuke Harada, Noriyuki Fujima, Takashi Mori, Takayuki Hashimoto, Emi Takakuwa, Atsushi Manabe, Kohsuke Kudo, Hidefumi Aoyama, Miki Fujimura
Journal of neurosurgery. Pediatrics, 1, 8, 2022年09月09日, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, OBJECTIVE: In patients with intracranial germ cell tumors, residual lesions are sometimes observed after completion of primary chemoradiotherapy. Although salvage resection of these end-of-treatment residual lesions is recommended for patients with nongerminomatous germ cell tumors, the necessity of early salvage resection for those with germinoma is not clear. The aim of this study was to investigate the frequency of residual germinoma lesions after primary chemoradiotherapy, as well as their management, long-term consequences, and prognosis. METHODS: The authors retrospectively reviewed patients who were primarily treated for germinoma between 2002 and 2021. Residual lesions were evaluated with MRI with and without contrast enhancement within 2 weeks after chemoradiotherapy. The decision to perform salvage resection of residual lesions was at the discretion of the treating physicians. The change in appearance of residual lesions was assessed with serial MRI. Overall survival (OS), progression-free survival (PFS), and recurrence pattern were also investigated. RESULTS: Sixty-nine patients were treated with chemoradiotherapy for germinoma, with a mean follow-up period of 108 months. Residual lesions were radiologically observed in 30 patients (43.5%). Among these, 5 patients (3 with pineal lesions and 2 with basal ganglia lesions) underwent salvage resection. Pathological examination revealed teratomatous components in 3 patients, whereas no tumoral components were identified in 2 patients. One patient with a basal ganglia lesion showed worsening of hemiparesis postoperatively. The remaining 25 patients received watchful observation without surgical intervention. Chronological periodic radiological change in residual lesions was evaluated in 21 patients. One year after primary treatment, the size of the residual lesions was stable and had decreased in 10 and 11 patients, respectively. None of the lesions increased in size. The 10-year PFS and OS rates were 96.7% and 97.3% in patients without residual lesions (n = 39), and 87.1% and 100% in patients with residual lesions (n = 30), respectively. Presence of residual lesions had no significant effect on PFS or OS. All recurrences occurred at distant sites or via dissemination without progression of the primary tumor site, regardless of the presence of residual lesion. CONCLUSIONS: End-of-treatment residual lesions are not rare in patients with germinoma, and these residual lesions seldom show progression. Because of the potential risk of surgical complications, the indication for early salvage surgery for residual lesions should be carefully determined. Watchful observation is recommended for the majority of these cases.

Arterial Spin Labelingを用いた短時間Functional MRIの検討　　　　　　　　　　　　　　　
林 哲司, 浜口 明巧, 藤間 憲幸, 原田 太以佑
JART: 日本診療放射線技師会誌, 69, 9, 1013, 1013, (公社)日本診療放射線技師会, 2022年09月
日本語

Arterial Spin Labelingを用いた短時間Functional MRIの検討　　　　　　　　　　　　　　　
林 哲司, 浜口 明巧, 藤間 憲幸, 原田 太以佑
JART: 日本診療放射線技師会誌, 69, 9, 1013, 1013, (公社)日本診療放射線技師会, 2022年09月
日本語

The utility of diffusion-weighted T2 mapping for the prediction of histological tumor grade in patients with head and neck squamous cell carcinoma.
Noriyuki Fujima, Yukie Shimizu, Masami Yoneyama, Junichi Nakagawa, Hiroyuki Kameda, Taisuke Harada, Seijiro Hamada, Takayoshi Suzuki, Nayuta Tsushima, Satoshi Kano, Akihiro Homma, Kohsuke Kudo
Quantitative imaging in medicine and surgery, 12, 8, 4024, 4032, 2022年08月, ［国際誌］
英語, 研究論文（学術雑誌）, Background: In head and neck cancers, histopathological information is important for the determination of the tumor characteristics and for predicting the prognosis. The aim of this study was to assess the utility of diffusion-weighted T2 (DW-T2) mapping for the evaluation of tumor histological grade in patients with head and neck squamous cell carcinoma (SCC). Methods: The cases of 41 patients with head and neck SCC (21 well/moderately and 17 poorly differentiated SCC) were retrospectively analyzed. All patients received MR scanning using a 3-Tesla MR unit. The conventional T2 value, DW-T2 value, ratio of DW-T2 value to conventional T2 value, and apparent diffusion coefficient (ADC) were calculated using signal information from the DW-T2 mapping sequence with a manually placed region of interest (ROI). Results: ADC values in the poorly differentiated SCC group were significantly lower than those in the moderately/well differentiated SCC group (P<0.05). The ratio of DW-T2 value to conventional T2 value was also significantly different between poorly and moderately/well differentiated SCC groups (P<0.01). Receiver operating characteristic (ROC) curve analysis of ADC values showed a sensitivity of 0.76, specificity of 0.67, positive predictive value (PPV) of 0.62, negative predictive value (NPV) of 0.8, accuracy of 0.71 and area under the curve (AUC) of 0.73, whereas the ROC curve analysis of the ratio of DW-T2 value to conventional T2 value showed a sensitivity of 0.76, specificity of 0.83, PPV of 0.76, NPV of 0.83, accuracy of 0.8 and AUC of 0.82. Conclusions: DW-T2 mapping might be useful as supportive information for the determination of tumor histological grade in patients with head and neck SCC.

Amide proton transfer imaging for the determination of human papillomavirus status in patients with oropharyngeal squamous cell carcinoma.
Noriyuki Fujima, Yukie Shimizu, Masami Yoneyama, Junichi Nakagawa, Hiroyuki Kameda, Taisuke Harada, Seijiro Hamada, Takayoshi Suzuki, Nayuta Tsushima, Satoshi Kano, Akihiro Homma, Kohsuke Kudo
Medicine, 101, 28, e29457, 2022年07月15日, ［国際誌］
英語, 研究論文（学術雑誌）, The aim of this study was to investigate the utility of amide proton transfer (APT) imaging for the determination of human papillomavirus (HPV) status in patients with oropharyngeal squamous cell carcinoma (SCC). Thirty-one patients with oropharyngeal SCC were retrospectively evaluated. All patients underwent amide proton transfer imaging using a 3T magnetic resonance (MR) unit. Patients were divided into HPV-positive and -negative groups depending on the pathological findings in their primary tumor. In APT imaging, the primary tumor was delineated with a polygonal region of interest (ROI). Signal information in the ROI was used to calculate the mean, standard deviation (SD) and coefficient of variant (CV) of the APT signals (APT mean, APT SD, and APT CV, respectively). The value of APT CV in the HPV-positive group (0.43 ± 0.04) was significantly lower than that in the HPV-negative group (0.48 ± 0.04) (P = .01). There was no significant difference in APT mean (P = .82) or APT SD (P = .13) between the HPV-positive and -negative groups. Receiver operating characteristic (ROC) curve analysis of APT CV had a sensitivity of 0.75, specificity of 0.8, positive predictive value of 0.75, negative predictive value of 0.8, accuracy of 0.77 and area under the curve (AUC) of 0.8. The APT signal in the HPV-negative group was considered heterogeneous compared to the HPV-positive group. This information might be useful for the determination of HPV status in patients with oropharyngeal SCC.

Quantitative Susceptibility Mapping: Basic Methods and Clinical Applications.
Taisuke Harada, Kohsuke Kudo, Noriyuki Fujima, Masato Yoshikawa, Yohei Ikebe, Ryota Sato, Toru Shirai, Yoshitaka Bito, Ikuko Uwano, Mari Miyata
Radiographics : a review publication of the Radiological Society of North America, Inc, 42, 4, 210054, 210054, 2022年05月06日, ［国際誌］
英語, 研究論文（学術雑誌）, Quantitative susceptibility mapping (QSM), one of the advanced MRI techniques for evaluating magnetic susceptibility, offers precise quantitative measurements of spatial distributions of magnetic susceptibility. Magnetic susceptibility describes the magnetizability of a material to an applied magnetic field and is a substance-specific value. Recently, QSM has been widely used to estimate various levels of substances in the brain, including iron, hemosiderin, and deoxyhemoglobin (paramagnetism), as well as calcification (diamagnetism). By visualizing iron distribution in the brain, it is possible to identify anatomic structures that are not evident on conventional images and to evaluate various neurodegenerative diseases. It has been challenging to apply QSM in areas outside the brain because of motion artifacts from respiration and heartbeats, as well as the presence of fat, which has a different frequency to the proton. In this review, the authors provide a brief overview of the theoretical background and analyze methods of converting MRI phase images to QSM. Moreover, we provide an overview of the current clinical applications of QSM. Online supplemental material is available for this article. ©RSNA, 2022.

Phase I Randomized Trial of ¹⁷ O ‐Labeled Water: Safety and Feasibility Study of Indirect Proton MRI for the Evaluation of Cerebral Water Dynamics
Taisuke Harada, Kohsuke Kudo, Hiroyuki Kameda, Ryota Sato, Toru Shirai, Yoshitaka Bito, Noriyuki Fujima, Satonori Tsuneta, Toshifumi Nogawa, Kenichiro Maeda, Hiroshi Hayashi, Makoto Sasaki
Journal of Magnetic Resonance Imaging, Wiley, 2022年04月30日
研究論文（学術雑誌）

Quantitative magnetic resonance imaging for evaluating of the cerebrospinal fluid kinetics with 17O-labeled water tracer: A preliminary report.
Hiroyuki Sugimori, Hiroyuki Kameda, Taisuke Harada, Kinya Ishizaka, Masayoshi Kajiyama, Tasuku Kimura, Niki Udo, Masaaki Matsushima, Azusa Nagai, Masahiro Wakita, Ichiro Kusumi, Ichiro Yabe, Kohsuke Kudo
Magnetic resonance imaging, 87, 77, 85, 2022年04月, ［国際誌］
英語, 研究論文（学術雑誌）, The aim of this study was to evaluate the feasibility of kinetic analysis of cerebrospinal fluid (CSF) using 17O-labeled water tracer. Four subjects (two idiopathic normal pressure hydrocephalus (iNPH) and two possible AD dementia patients) were prospectively included. Injectable formulation of 17O-labeled water containing 10 mol% of H217O (PSO17), was intrathecally administered to the subjects with the lateral decubitus position between the 3rd and 4th lumbar vertebrae. MRI acquisitions were performed in four-time points, before PSO17 administration, 1, 8, and 24 h after PSO17 administration. The 3-dimensional fast spin echo sequence was used. After image registration for all four-time points data, polygonal regions of interest (ROIs) were set in the 14 regions to obtain the signal intensity of CSF. Each signal intensity within the ROI was converted to 17O concentration [%]. The peak concentration at one hour after administration, the slope of concentration changes after PSO17 administration [%/s], and the root mean square error (RMSE) for evaluating the performance of a fitting were calculated. There was no significant difference in peak concentration between the iNPH and AD group. The slope in the AD group (-2.25 ± 1.62 × 10-3 [%/h]) was significantly smaller than in the iNPH group (-1.21 ± 2.31 × 10-3 [%/h]), which suggests the speed of CSF clearance in the iNPH group was slower than AD group. The RMSE indicating the fit to the concentration change in the AD group (4.86 ± 4.74 × 10-3) was also significantly smaller than in the iNPH group (8.64 ± 7.56 × 10-3). The kinetic evaluation of CSF using 17O-labeled water was feasible, and this preliminary study suggests that the differentiation of iNPH and possible AD dementia can be achieved using this method.

Variations and natural history of primary intraparenchymal lesions associated with neurofibromatosis type 2.
Yukitomo Ishi, Taisuke Harada, Hiroyuki Kameda, Hiromi Okada, Isao Yokota, Michinari Okamoto, Ryosuke Sawaya, Hiroaki Motegi, Shigeru Yamaguchi, Shunsuke Terasaka, Kohsuke Kudo, Miki Fujimura
Neuroradiology, 64, 2, 393, 396, 2021年11月23日, ［国際誌］
英語, 研究論文（学術雑誌）, The study aimed to investigate the clinical implications and natural history of primary intraparenchymal lesions in patients with neurofibromatosis type 2. Radiological findings of 15 neurofibromatosis type 2 cases were retrospectively collected. Twenty-seven primary intraparenchymal lesions were observed in 7 out of 15 patients (47%). Cortical/subcortical T2 hyperintense lesions and enlarged Virchow-Robin spaces were the most common findings in five and four patients, respectively. During the follow-up period (median 84 months), one new primary intraparenchymal lesion was identified and increased lesions were observed in two cases on contrast-enhanced MRI. Surgical resection was performed in one case pathologically diagnosed with atypical meningioma. Twenty-five other lesions without contrast enhancement presented no apparent growth during follow-up. Although most primary intraparenchymal lesions are benign, a subset of cases would present newly developed or increased lesions on contrast-enhanced MRI. Careful monitoring is necessary for such cases, and pathological confirmation should be considered.

Quantitative Susceptibility Mapping versus R2*-based Histogram Analysis for Evaluating Liver Fibrosis: Preliminary Results.
Masato Yoshikawa, Kohsuke Kudo, Taisuke Harada, Kazutaka Harashima, Jun Suzuki, Koji Ogawa, Taro Fujiwara, Mutsumi Nishida, Ryota Sato, Toru Shirai, Yoshitaka Bito
Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine, 2021年09月04日, ［国内誌］
英語, 研究論文（学術雑誌）, PURPOSE: The staging of liver fibrosis is clinically important, and a less invasive method is preferred. Quantitative susceptibility mapping (QSM) has shown a great potential in estimating liver fibrosis in addition to R2* relaxometry. However, few studies have compared QSM analysis and liver fibrosis. We aimed to evaluate the feasibility of estimating liver fibrosis by using QSM and R2*-based histogram analyses by comparing it with ultrasound-based transient elastography and the stage of histologic fibrosis. METHODS: Fourteen patients with liver disease were enrolled. Data sets of multi-echo gradient echo sequence with breath-holding were acquired on a 3-Tesla scanner. QSM and R2* were reconstructed by water-fat separation method, and ROIs were analyzed for these images. Quantitative parameters with histogram features (mean, variance, skewness, kurtosis, and 1st, 10th, 50th, 90th, and 99th percentiles) were extracted. These data were compared with the elasticity measured by ultrasound transient elastography and histological stage of liver fibrosis (F0 to F4, based on the new Inuyama classification) determined by biopsy or hepatectomy. The correlation of histogram parameters with intrahepatic elasticity and histologically confirmed fibrosis stage was examined. Texture parameters were compared between subgroups divided according to fibrosis stage. Receiver operating characteristic (ROC) analysis was also performed. P < 0.05 indicated statistical significance. RESULTS: The six histogram parameters of both QSM and R2*were significantly correlated with intrahepatic elasticity. In particular, three parameters (variance, percentiles [90th and 99th]) of QSM showed high correlation (r = 0.818-0.844), whereas R2* parameters showed a moderate correlation with elasticity. Four parameters of QSM were significantly correlated with fibrosis stage (ρ = 0.637-0.723) and differentiated F2-4 from F0-1 fibrosis and F3-4 from F0-2 fibrosis with areas under the ROC curve of > 0.8, but those of R2* did not. CONCLUSION: QSM may serve as a promising surrogate indicator in detecting liver fibrosis.

Pearls & Oy-sters: Adult-Onset Alexander Disease With Transient Swelling of the Medulla Oblongata.
Yuki Oshima, Ikuko Takahashi-Iwata, Shoki Sato, Taisuke Harada, Tomokatsu Yoshida, Ichiro Yabe
Neurology, 2021年05月26日, ［国際誌］
英語, 研究論文（学術雑誌）

Texture analysis of delayed contrast-enhanced computed tomography to diagnose cardiac sarcoidosis.
Satonori Tsuneta, Noriko Oyama-Manabe, Kenji Hirata, Taisuke Harada, Tadao Aikawa, Osamu Manabe, Hiroshi Ohira, Kazuhiro Koyanagawa, Masanao Naya, Kohsuke Kudo
Japanese journal of radiology, 39, 5, 442, 450, 2021年05月, ［国内誌］
英語, 研究論文（学術雑誌）, PURPOSE: To investigate the diagnostic value of texture analysis to differentiate cardiac sarcoidosis (CS) from other non-ischemic cardiomyopathies (non-CS). MATERIALS AND METHODS: Twenty CS patients and 15 non-CS patients who had undergone myocardial CT delayed enhancement (CTDE) were included. A total of 36 texture features were calculated according to the CT attenuation of CTDE. We investigated the diagnostic value to differentiate CS from non-CS. We also assessed the intra- and inter-rater reproducibility for each feature and inter-observer agreement for visual assessment. RESULTS: Seven extracted features had significantly higher run length non-uniformity (RLNU) values (5.4 × 102 ± 6.2 × 102 vs. 11.2 × 102 ± 4.9 × 102, p = 0.037) and significantly lower low gray-level zone emphasis (LGZE) values (7.1 × 10-3 ± 8.6 × 10-3 vs. 18.1 × 10-3 ± 16.9 × 10-3, p = 0.017) in CS than in non-CS. Intra- and inter-rater reproducibility of RLNU and LGZE were excellent (ICCs > 0.8), while inter-observer agreement of visual assessment was poor (kappa = 0.19). The accuracies of texture analysis were 69% with RLNU and 71% with LGZE, which were better than that of visual assessment. CONCLUSION: Texture analysis of CTDE could differentiate CS from non-CS with high reproducibility.

画像診断と病理 髄芽腫(desmoplastic/nodular type)
竹中 淳規, 山口 晃典, 原田 太以佑, 工藤 與亮, 高桑 恵美, 山口 秀
画像診断, 40, 14, 1394, 1395, (株)学研メディカル秀潤社, 2020年11月
日本語

画像診断と病理 粘液線維肉腫
原嶋 十考, 中川 純一, 原田 太以佑, 坂本 圭太, 工藤 與亮, 中里 信一, 清水 亜衣
画像診断, 40, 12, 1158, 1159, (株)学研メディカル秀潤社, 2020年09月
日本語

Detection of impaired cerebrovascular reactivity in patients with chronic cerebral ischemia using whole-brain 7T MRA.
Ikuko Uwano, Hiroyuki Kameda, Taisuke Harada, Masakazu Kobayashi, Wataru Yanagihara, Kengo Setta, Kuniaki Ogasawara, Kunihiro Yoshioka, Fumio Yamashita, Futoshi Mori, Tsuyoshi Matsuda, Makoto Sasaki
Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association, 29, 9, 105081, 105081, 2020年09月, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, BACKGROUND: Cerebrovascular reactivity (CVR) to acetazolamide (ACZ) on single-photon emission computed tomography (SPECT) can be used to assess the severity of chronic cerebral ischemia; however, this is an invasive method. We examined whether whole-brain magnetic resonance angiography (MRA) at 7T could non-invasively detect impaired CVR in patients with chronic cerebral ischemia by demonstrating the leptomeningeal collaterals (LMCs). METHODS: Fifty-seven patients with symptomatic unilateral cervical stenosis underwent whole-brain time-of-flight MRA at 7T and cerebral perfusion SPECT before/after the ACZ challenge. MRA images were visually assessed based on 6-point grading systems to evaluate the development of LMCs toward the middle cerebral artery (MCA) and antegrade flow of MCA. CVR of the affected side was calculated from the SPECT data. Subsequently, we compared the LMC grades on MRA with CVR on SPECT. RESULTS: CVR was significantly lower in grades ≥ 2 of LMCs than in grades 0-1 (P < 0.05) when applying LMCs from the anterior cerebral artery (ACA) and/or posterior cerebral artery (PCA). These differences were more evident than those in the grading of the antegrade MCA flow. The LMC grades from ACA/PCA readily detected reduced CVR (< 18.4%) with a sensitivity/specificity of 0.79/0.82. CONCLUSION: The development of LMCs on whole-brain MRA at 7T can non-invasively detect reduced CVR with a high sensitivity/specificity in patients with unilateral cervical stenosis.

画像診断と病理 鼻腔軟骨肉腫
曽々木 昇, 志村 亮祐, 原田 太以佑, 工藤 與亮, 清水 亜衣, 松野 吉宏
画像診断, 40, 9, 902, 903, (株)学研メディカル秀潤社, 2020年07月
日本語

Improvement of image quality on low-dose dynamic myocardial perfusion computed tomography with a novel 4-dimensional similarity filter.
Satonori Tsuneta, Noriko Oyama-Manabe, Hiroyuki Kameda, Taisuke Harada, Fumi Kato, Ewoud J Smit, Mathias Prokop, Kohsuke Kudo
Medicine, 99, 26, e20804, 2020年06月26日, ［国際誌］
英語, 研究論文（学術雑誌）, The aim of this study was to evaluate the effect of a novel 4-dimensional similarity filter (4DSF) on quantitative and qualitative parameters of low-dose dynamic myocardial computed tomography perfusion (CTP) images.In this retrospective study, medical records of 32 patients with suspected or known coronary artery disease who underwent dynamic myocardial CTP at 80 kV were included. The 4DSF reduces noise by averaging voxels that have similar dynamic behavior after adaptive iterative dose reduction 3D (AIDR3D) and deformable image registration were applied. Qualitative (artefact, contour sharpness, and myocardial homogeneity [1 = poor; 2 = intermediate; 3 = good]) and quantitative measurement (standard deviation [SD] and signal-to-noise ratio [SNR]) were compared between the 4DSF and AIDR3D. Contrast-to-noise ratio (CNR) between ischemic and normal remote myocardium was also assessed using myocardial perfusion magnetic resonance imaging as the reference standard in seven patients.The 4DSF was successfully applied to all the images. Improvement in subjective image quality yielded by 4DSF was higher than that yielded by AIDR3D (homogeneity, 1.0 [3 vs 2]; artefact, 1.5 [3 vs 1.5]; P < .001) in all patients. The 4DSF significantly decreased the SD by 59% (AIDR3D vs 4DSF: 33.5 ± 0.4 vs 13.8 ± 0.4, P < .001), increased the SNR by 134% (AIDR3D vs 4DSF: 4.4 ± 0.2 vs 10.3 ± 0.2, P < .001), and increased the CNR by 131% (AIDR3D vs 4DSF: 1.6 ± 0.2 vs 3.7 ± 0.2, P < .001).The 4DSF improved the qualitative and quantitative parameters of low-dose dynamic myocardial CTP images.

画像診断と病理 縦隔原発混合型胚細胞腫瘍
井浦 孝紀, 吉川 仁人, 原田 太以佑, 工藤 與亮, 清水 亜衣, 松野 吉宏
画像診断, 40, 8, 776, 777, (株)学研メディカル秀潤社, 2020年06月
日本語, ＜文献概要＞症例は10歳代,男性.息苦しさと左胸痛を自覚,胸部単純X線写真(非提示)で縦隔腫瘍が疑われた.造影CTでは,前縦隔に12cm大の境界明瞭で分葉状形態を示す腫瘤を認め,内部は不均一な造影効果を示し,不整形な石灰化が散見された他,脂肪の吸収値を示す小構造が認められた.MRIでは,T2強調像で大部分は不均一な高信号を示し,大小の嚢胞成分を伴っていた.また,脂肪抑制T1強調像で病変の一部に地図状の高信号域を認め,出血が疑われた.腫瘍マーカーは,hCG-β 131.1mIU/ml(正常値<0.5mIU/ml),AFP 9077.7ng/ml(1.0〜10.0ng/ml)といずれも異常高値であった.以上の画像所見および臨床情報から,混合型胚細胞腫瘍を強く疑った.なお,精巣には腫大や左右差を認めなかった.

Utility of a diffusion-weighted arterial spin labeling (DW-ASL) technique for evaluating the progression of brain white matter lesions.
Noriyuki Fujima, Hiroyuki Kameda, Yukie Shimizu, Taisuke Harada, Khin Khin Tha, Masami Yoneyama, Kohsuke Kudo
Magnetic resonance imaging, 69, 81, 87, 2020年06月, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, PURPOSE: To investigate the utility of diffusion-weighted arterial spin labeling (DW-ASL) for detecting the progression of brain white matter lesions. MATERIALS AND METHODS: A total of 492 regions of interest (ROIs) in 41 patients were prospectively analyzed. DW-ASL was performed using the diffusion gradient prepulse of five b-values (0, 25, 60, 102, and 189) before the ASL readout. We calculated the water exchange rate (Kw) with post-processing using the ASL signal information for each b-value. The cerebral blood flow (CBF) was also calculated using b0 images. Using the signal information in FLAIR (fluid-attenuated inversion recovery) images, we classified the severity of white matter lesions into three grades: non-lesion, moderate, and severe. In addition, the normal Kw level was measured from DW-ASL data of 60 ROIs in five control subjects. The degree of variance of the Kw values (Kw-var) was calculated by squaring the value of the difference between each Kw value and the normal Kw level. All patient's ROIs were divided into non-progressive and progressive white matter lesions by comparing the present FLAIR images with those obtained 2 years before this acquisition. RESULTS: Compared to the non-progressive group, the progressive group had significantly lower CBF, significantly higher severity grades in FLAIR, and significantly greater Kw-var values. In a receiver operator characteristic curve analysis, a high area under the curve (AUC) of 0.89 was obtained with the use of Kw-var. In contrast, the AUCs of 0.59 for CBF and 0.72 for severity grades in FLAIR were obtained. CONCLUSIONS: The DW-ASL technique can be useful to detect the progression of brain white matter lesions. This technique will become a clinical tool for patients with various degrees of white matter lesions.

小脳型多系統萎縮症におけるプロトン密度強調画像を用いた小脳の信号強度の検討　　　　　　　　　　　　　　　
山口 晃典, 原田 太以佑, 工藤 與亮, 松島 理明, 矢部 一郎, 佐々木 秀直
Japanese Journal of Radiology, 38, Suppl., 1, 1, (公社)日本医学放射線学会, 2020年02月
日本語

Somatic malignant transformationが疑われたgerm cell tumor再発の1例　　　　　　　　　　　　　　　
高柳 歩, 原田 太以佑, 藤間 憲幸, 工藤 與亮, 岡田 宏美, 山口 秀, 小林 浩之
Japanese Journal of Radiology, 38, Suppl., 7, 7, (公社)日本医学放射線学会, 2020年02月
日本語

Computational Fluid Dynamics Analysis of Lateral Striate Arteries in Acute Ischemic Stroke Using 7T High-resolution Magnetic Resonance Angiography.
Futoshi Mori, Fujimaro Ishida, Tatsunori Natori, Haruna Miyazawa, Hiroyuki Kameda, Taisuke Harada, Kunihiro Yoshioka, Fumio Yamashita, Ikuko Uwano, Kenji Ito, Makoto Sasaki
Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association, 28, 11, 104339, 104339, 2019年11月, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, BACKGROUND: Infarcts in the lateral striate artery (LSA) territory can be caused by several pathological changes, including lipohyalinosis and microatheroma. However, fluid dynamic effects on these changes remain unknown. Thus, we investigated whether the fluid dynamic metrics of the LSAs were altered in patients with acute ischemic stroke using computational fluid dynamics (CFD) analysis. METHODS: Fifty-one patients with acute ischemic stroke confined in the basal ganglia and/or corona radiata underwent high-resolution magnetic resonance angiography (HR-MRA) at 7T. We performed CFD analyses to obtain indices including the wall shear stress (WSS), WSS gradient (WSSG), and flow velocity (FV) and compared these values between the ipsilesional and contralesional sides in the patients with infarcts in the LSA or non-LSA territories. RESULTS: In patients with LSA-territory infarcts, the WSS, WSSG, and FV values were significantly lower in the ipsilesional LSAs than in the contralesional LSAs (P = .01-.03), while these values in the proximal middle cerebral arteries showed no significant lateralities. In contrast, in patients with non-LSA-territory infarcts, there were no significant lateralities in the metrics between the ipsilesional and contralesional sides. CONCLUSIONS: The CFD analyses using HR-MRA revealed significantly low WSS and WSSG values of the ipsilesional LSAs compared with that of the contralesional side in patients with LSA-territory infarcts, suggesting that fluid dynamic factors of LSAs can be one of the risk factors for LSA-territory infarctions.

Prediction of Hypoxia in Brain Tumors Using a Multivariate Model Built from MR Imaging and ¹⁸F-Fluorodeoxyglucose Accumulation Data.
Shimizu Y, Kudo K, Kameda H, Harada T, Fujima N, Toyonaga T, Tha KK, Shirato H
Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine, 19, 3, 227, 234, 2019年10月, ［査読有り］, ［国内誌］
英語, 研究論文（学術雑誌）, PURPOSE: The aim of this study was to generate a multivariate model using various MRI markers of blood flow and vascular permeability and accumulation of 18F-fluorodeoxyglucose (FDG) to predict the extent of hypoxia in an 18F-fluoromisonidazole (FMISO)-positive region. METHODS: Fifteen patients aged 27-74 years with brain tumors (glioma, n = 13; lymphoma, n = 1; germinoma, n = 1) were included. MRI scans were performed using a 3T scanner, and dynamic contrast-enhanced (DCE) perfusion and arterial spin labeling images were obtained. Ktrans and Vp maps were generated using the DCE images. FDG and FMISO positron emission tomography scans were also obtained. A model for predicting FMISO positivity was generated on a voxel-by-voxel basis by a multivariate logistic regression model using all the MRI parameters with and without FDG. Receiver-operating characteristic curve analysis was used to detect FMISO positivity with multivariate and univariate analysis of each parameter. Cross-validation was performed using the leave-one-out method. RESULTS: The area under the curve (AUC) was highest for the multivariate prediction model with FDG (0.892) followed by the multivariate model without FDG and univariate analysis with FDG and Ktrans (0.844 for all). In cross-validation, the multivariate model with FDG had the highest AUC (0.857 ± 0.08) followed by the multivariate model without FDG (0.834 ± 0.119). CONCLUSION: A multivariate prediction model created using blood flow, vascular permeability, and glycometabolism parameters can predict the extent of hypoxia in FMISO-positive areas in patients with brain tumors.

17O標識水の第1相臨床試験 安全性および脳血流MRIの実現可能性に関する検討
原田 太以佑, 工藤 與亮, 亀田 浩之, 佐藤 良太, 白猪 亨, 尾藤 良孝, 藤間 憲幸, 常田 慧徳, 野川 敏史, 前田 憲一郎, 林 宏至, 佐々木 真理
日本磁気共鳴医学会雑誌, 39, 2, 66, 66, (一社)日本磁気共鳴医学会, 2019年05月
日本語

The utility of MRI histogram and texture analysis for the prediction of histological diagnosis in head and neck malignancies
Fujima Noriyuki, Homma Akihiro, Harada Taisuke, Shimizu Yukie, Tha Khin Khin, Kano Satoshi, Mizumachi Takatsugu, Li Ruijiang, Kudo Kohsuke, Shirato Hiroki
CANCER IMAGING, 19, 2019年02月04日, ［査読有り］

The utility of MRI histogram and texture analysis for the prediction of histological diagnosis in head and neck malignancies.
Noriyuki Fujima, Akihiro Homma, Taisuke Harada, Yukie Shimizu, Khin Khin Tha, Satoshi Kano, Takatsugu Mizumachi, Ruijiang Li, Kohsuke Kudo, Hiroki Shirato
Cancer imaging : the official publication of the International Cancer Imaging Society, 19, 1, 5, 5, 2019年02月04日, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, BACKGROUND: To assess the utility of histogram and texture analysis of magnetic resonance (MR) fat-suppressed T2-weighted imaging (Fs-T2WI) for the prediction of histological diagnosis of head and neck squamous cell carcinoma (SCC) and malignant lymphoma (ML). METHODS: The cases of 57 patients with SCC (45 well/moderately and 12 poorly differentiated SCC) and 10 patients with ML were retrospectively analyzed. Quantitative parameters with histogram features (relative mean signal, coefficient of variation, kurtosis and skewness) and gray-level co-occurrence matrix (GLCM) features (contrast, correlation, energy and homogeneity) were calculated using Fs-T2WI data with a manual tumor region of interest (ROI). RESULTS: The following significantly different values were obtained for the total SCC versus ML groups: relative mean signal (3.65 ± 0.86 vs. 2.61 ± 0.49), contrast (72.9 ± 16.2 vs. 49.3 ± 8.7) and homogeneity (2.22 ± 0.25 × 10- 1 vs. 2.53 ± 0.12 × 10- 1). In the comparison of the SCC histological grades, the relative mean signal and contrast were significantly lower in the poorly differentiated SCC (2.89 ± 0.63, 56.2 ± 12.9) compared to the well/moderately SCC (3.85 ± 0.81, 77.5 ± 13.9). The homogeneity in poorly differentiated SCC (2.56 ± 0.15 × 10- 1) was higher than that of the well/moderately SCC (2.1 ± 0.18 × 10- 1). CONCLUSIONS: Parameters obtained by histogram and texture analysis of Fs-T2WI may be useful for noninvasive prediction of histological type and grade in head and neck malignancy.

特徴的な画像所見を呈した鞍上部immature teratomaの1例　　　　　　　　　　　　　　　
藤井 宝顕, 原田 太以佑, 清水 幸衣, 藤間 憲幸, Tha Khin Khin, 工藤 與亮, 寺坂 俊介, 長 祐子, 白土 博樹
Japanese Journal of Radiology, 37, Suppl., 4, 4, (公社)日本医学放射線学会, 2019年02月
日本語

くも膜下出血後にびまん性の白質障害を呈した1例　　　　　　　　　　　　　　　
古家 翔, 原田 太以佑, 清水 幸衣, 藤間 憲幸, Tha Khin Khin, 工藤 與亮, 月花 正幸, 中山 若樹, 白土 博樹
Japanese Journal of Radiology, 37, Suppl., 10, 10, (公社)日本医学放射線学会, 2019年02月
日本語

くも膜下出血後にびまん性の白質障害を呈した一例
古家 翔, 原田 太以佑, 清水 幸衣, 藤間 憲幸, Tha Khin Khin, 工藤 與亮, 月花 正幸, 中山 若樹, 白土 博樹
核医学, 55, 1, 40, 40, (一社)日本核医学会, 2018年12月
日本語

[A Diagnostic Imaging Approach for Tremor].
Taisuke Harada, Kohsuke Kudo
Brain and nerve = Shinkei kenkyu no shinpo, 70, 12, 1331, 1340, 2018年12月, ［査読有り］, ［国内誌］
日本語, 研究論文（学術雑誌）, Tremor is one of the common movement disorders encountered in a clinical practice. Tremor is often difficult to diagnose and can be easily mistaken for another disorder, hence diagnostic imaging is employed to provide objective information. The morphometry, signal changes, neuromelanin, and iron deposition can be evaluated by MRI, whereas cardiac sympathetic nerve and dopamine transporter degeneration are detected by means of nuclear medicine. The purpose of this article is to provide an overview of the role and indications of imaging test, as well as a review of the methods in which the findings of images are interpreted.

【Step up MRI 2018 MRI新技術 基礎から臨床への橋渡し】MRIの新技術 臨床編 頭部領域におけるMRIの新技術と臨床応用 定量的磁化率マッピングの臨床応用
原田 太以佑, 藤間 憲幸, 工藤 與亮
INNERVISION, 33, 9, 37, 40, (株)インナービジョン, 2018年08月
日本語, 磁化率は組織固有の物理的性質であり、その画像化として磁化率強調画像(susceptibility weighted imaging:SWI)や位相差強調画像(phase difference enhanced imaging:PADRE)が定性画像として用いられている。近年では、MRIを用いた定量化が一つのテーマとなっており、定量的磁化率マッピング(quantitative susceptibility mapping:QSM)は、磁化率を定量的に評価できる方法として、ここ数年で臨床研究の報告が急増している。本稿では、QSMの臨床応用と最近の知見について概説する。(著者抄録)

Indirect Proton MR Imaging and Kinetic Analysis of 17O-Labeled Water Tracer in the Brain.
Kohsuke Kudo, Taisuke Harada, Hiroyuki Kameda, Ikuko Uwano, Fumio Yamashita, Satomi Higuchi, Kunihiro Yoshioka, Makoto Sasaki
Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine, 17, 3, 223, 230, 2018年07月10日, ［査読有り］, ［国内誌］
英語, 研究論文（学術雑誌）, PURPOSE: The feasibility of steady-state sequences for 17O imaging was evaluated based on a kinetic analysis of the brain parenchyma and cerebrospinal fluid (CSF). MATERIALS AND METHODS: The institutional review board approved this prospective study with written informed consent. Dynamic 2D or 3D steady-state sequences were performed in five and nine participants, respectively, with different parameters using a 3T scanner. During two consecutive dynamic scans, saline was intravenously administered for control purposes in the first scan, and 20% 17O-labeled water (1 mL/Kg) was administered in the second scan. Signal changes relative to the baseline were calculated, and kinetic analyses of the curves were conducted for all voxels. Region of interest analysis was performed in the brain parenchyma, choroid plexus, and CSF spaces. RESULTS: Average signal drops were significantly larger in the 17O group than in the controls for most of the imaging parameters. Different kinetic parameters were observed between the brain parenchyma and CSF spaces. Average and maximum signal drops were significantly larger in the CSF spaces and choroid plexus than in the brain parenchyma. Bolus arrival, time to peak, and the first moment of dynamic curves of 17O in the CSF space were delayed compared to that in the brain parenchyma. Significant differences between the ventricle and subarachnoid space were also noted. CONCLUSION: Steady-state sequences are feasible for indirect 17O imaging with reasonable temporal resolution; this result is potentially important for the analysis of water kinetics and aquaporin function for several disorders.

Improvement of the repeatability of parallel transmission at 7T using interleaved acquisition in the calibration scan.
Hiroyuki Kameda, Kohsuke Kudo, Tsuyoshi Matsuda, Taisuke Harada, Yuji Iwadate, Ikuko Uwano, Fumio Yamashita, Kunihiro Yoshioka, Makoto Sasaki, Hiroki Shirato
Journal of magnetic resonance imaging : JMRI, 48, 1, 94, 101, 2018年07月, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, BACKGROUND: Respiration-induced phase shift affects B0 /B1+ mapping repeatability in parallel transmission (pTx) calibration for 7T brain MRI, but is improved by breath-holding (BH). However, BH cannot be applied during long scans. PURPOSE: To examine whether interleaved acquisition during calibration scanning could improve pTx repeatability and image homogeneity. STUDY TYPE: Prospective. SUBJECTS: Nine healthy subjects. FIELD STRENGTH/SEQUENCE: 7T MRI with a two-channel RF transmission system was used. ASSESSMENT: Calibration scanning for B0 /B1+ mapping was performed under sequential acquisition/free-breathing (Seq-FB), Seq-BH, and interleaved acquisition/FB (Int-FB) conditions. The B0 map was calculated with two echo times, and the B1+ map was obtained using the Bloch-Siegert method. Actual flip-angle imaging (AFI) and gradient echo (GRE) imaging were performed using pTx and quadrature-Tx (qTx). All scans were acquired in five sessions. Repeatability was evaluated using intersession standard deviation (SD) or coefficient of variance (CV), and in-plane homogeneity was evaluated using in-plane CV. STATISTICAL TESTS: A paired t-test with Bonferroni correction for multiple comparisons was used. RESULTS: The intersession CV/SDs for the B0 /B1+ maps were significantly smaller in Int-FB than in Seq-FB (Bonferroni-corrected P < 0.05 for all). The intersession CVs for the AFI and GRE images were also significantly smaller in Int-FB, Seq-BH, and qTx than in Seq-FB (Bonferroni-corrected P < 0.05 for all). The in-plane CVs for the AFI and GRE images in Seq-FB, Int-FB, and Seq-BH were significantly smaller than in qTx (Bonferroni-corrected P < 0.01 for all). DATA CONCLUSION: Using interleaved acquisition during calibration scans of pTx for 7T brain MRI improved the repeatability of B0 /B1+ mapping, AFI, and GRE images, without BH. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage 1 J. Magn. Reson. Imaging 2017.

Indirect MRI of 17 o-labeled water using steady-state sequences: Signal simulation and preclinical experiment.
Kohsuke Kudo, Taisuke Harada, Hiroyuki Kameda, Ikuko Uwano, Fumio Yamashita, Satomi Higuchi, Kunihiro Yoshioka, Makoto Sasaki
Journal of magnetic resonance imaging : JMRI, 47, 5, 1373, 1379, 2018年05月, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, BACKGROUND: Few studies have been reported for T2 -weighted indirect 17 O imaging. PURPOSE/HYPOTHESIS: To evaluate the feasibility of steady-state sequences for indirect 17 O brain imaging. STUDY TYPE: Signal simulation, phantom measurements, and prospective animal experiments were performed in accordance with the institutional guidelines for animal experiments. POPULATION/SUBJECTS/PHANTOM/SPECIMEN/ANIMAL MODEL: Signal simulations of balanced steady-state free precession (bSSFP) were performed for concentrations of 17 O ranging from 0.037-1.600%. Phantom measurements with concentrations of 17 O water ranging from 0.037-1.566% were also conducted. Six healthy beagle dogs were scanned with intravenous administration of 20% 17 O-labeled water (1 mL/kg). FIELD STRENGTH/SEQUENCE: Dynamic 3D-bSSFP scans were performed at 3T MRI. 17 O-labeled water was injected 60 seconds after the scan start, and the total scan duration was 5 minutes. ASSESSMENT: Based on the result of signal simulation and phantom measurement, signal changes in the beagle dogs were measured and converted into 17 O concentrations. STATISTICAL TESTS: The 17 O concentrations were averaged for every 15 seconds, and compared to the baseline (30-45 sec) with Dunnett's multiple comparison tests. RESULTS: Signal simulation revealed that the relationships between 17 O concentration and the natural logarithm of relative signals were linear. The intraclass correlation coefficient between relative signals in phantom measurement and signal simulations was 0.974. In the animal experiments, significant increases in 17 O concentration (P < 0.05) were observed 60 seconds after the injection of 17 O. At the end of scanning, mean respective 17 O concentrations of 0.084 ± 0.026%, 0.117 ± 0.038, 0.082 ± 0.037%, and 0.049 ± 0.004% were noted for the cerebral cortex, cerebellar cortex, cerebral white matter, and ventricle. DATA CONCLUSION: Dynamic steady-state sequences were feasible for indirect 17 O imaging, and absolute quantification was possible. This method can be applied for the measurement of permeability and blood flow in the brain, and for kinetic analysis of cerebrospinal fluid. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:1373-1379.

30年後の再発が疑われる脊髄Germinomaの1例　　　　　　　　　　　　　　　
木野田 直也, 原田 太以佑, 吉田 篤司, 清水 幸衣, 藤間 憲幸, 工藤 興亮, Khin Khin Tha, 白土 博樹, 山口 秀, 小林 浩之, 寺坂 俊介, 岡田 宏美, 畑中 佳奈子
Japanese Journal of Radiology, 36, Suppl., 3, 3, (公社)日本医学放射線学会, 2018年02月
日本語

長期間経過を追えたCerebral Amyloid Angiopathyの1例　　　　　　　　　　　　　　　
常田 慧徳, 原田 太以佑, 吉田 篤司, 清水 幸衣, 藤間 憲幸, 工藤 與亮, 西村 洋昭, 佐々木 秀直, Khin Khin Tha, 白土 博樹
Japanese Journal of Radiology, 36, Suppl., 13, 13, (公社)日本医学放射線学会, 2018年02月
日本語

亜急性連合性脊髄変性症の1例　　　　　　　　　　　　　　　
長島 諒太, 原田 太以佑, 吉田 篤司, 清水 幸衣, 藤間 憲幸, 工藤 與亮, Khin Khin Tha, 白土 博樹, 西村 洋昭, 佐々木 秀直
Japanese Journal of Radiology, 36, Suppl., 16, 16, (公社)日本医学放射線学会, 2018年02月
日本語

Value of T1-weighted magnetic resonance imaging in cholesteatoma detection
Atsushi Fukuda, Shinya Morita, Taisuke Harada, Keishi Fujiwara, Kimiko Hoshino, Yuji Nakamaru, Akihiro Homma
Otology and Neurotology, 38, 10, 1440, 1444, Lippincott Williams and Wilkins, 2017年12月01日, ［査読有り］
英語, Objective: To reveal the usefulness of T1-weighted (T1W) imaging on diagnostic magnetic resonance (MR) imaging for cholesteatoma. Study Design: A retrospective case review. Setting: Tertiary referral center. Patients: Fifty-three patients (57 ears) suspected to have cholesteatomas and treated (6-82 yr of age). Intervention: Preoperative MR imaging, including non-echo planar (non-EP) diffusion-weighted (DW) and T1W imaging. Main Outcome Measures: Primary outcome measures included the comparison between the diagnostic accuracy for the detection of cholesteatomas using non-EP DW imaging alone (criterion 1) and non-EP DW imaging along with T1W imaging (criterion 2). Diagnostic accuracy was evaluated in each case by comparing MR imaging with surgical findings. Secondary outcome measures included the comparison of the rates of cases showing a high T1W signal between cholesteatomas and noncholesteatomas which showed a high non-EP DW signal. Results: The sensitivity, specificity, and accuracy according to criterion 1 were 93.5, 63.6, and 87.7% and those according to criterion 2 were 89.1, 100, and 91.2%, respectively. Of 43 cholesteatoma cases indicating a high non-EP DW signal, only 2 cases showed a high T1W signal (5%). On the other hand, all four noncholesteatoma cases indicating high non-EP DW signal showed a high T1W signal (100%), and these rates were significantly different ( p<
0.001). Conclusion: Our results suggest that T1W imaging may aid in the exclusion of false-positive cases on diagnostic non-EP DW MR imaging for cholesteatomas. A combination of non- EP DW and T1W imaging may improve the specificity and accuracy compared with non-EP DW imaging alone.

【薬物治療に起因する諸病態の画像所見】中枢神経
原田 太以佑, 藤間 憲幸, 工藤 與亮
臨床画像, 33, 10, 1116, 1129, (株)メジカルビュー社, 2017年10月
日本語, 薬物治療に関連する中枢神経病変は非常に多彩であるが,画像診断医が薬剤性病変の可能性を言及することが肝要である。本稿では最近よく話題となっている分子標的薬に焦点をあてつつ,日常臨床でしばしば見かける薬剤関連病変の画像所見を概説する。(著者抄録)

Non-invasive prediction of the tumor growth rate using advanced diffusion models in head and neck squamous cell carcinoma patients
Noriyuki Fujima, Tomohiro Sakashita, Akihiro Homma, Taisuke Harada, Yukie Shimizu, Khin Khin Tha, Kohsuke Kudo, Hiroki Shirato
ONCOTARGET, 8, 20, 33631, 33643, IMPACT JOURNALS LLC, 2017年05月, ［査読有り］
英語, 研究論文（学術雑誌）, We assessed parameters of advanced diffusion weighted imaging (DWI) models for the prediction of the tumor growth rate in 55 head and neck squamous cell carcinoma (HNSCC) patients. The DWI acquisition used single-shot spin-echo echo-planar imaging with 12 b-values (0-2000). We calculated 14 DWI parameters using mono-exponential, bi-exponential, tri-exponential, stretched exponential and diffusion kurtosis imaging models. We directly measured the tumor growth rate from two sets of different-date imaging data. We divided the patients into a discovery group (n = 40) and validation group (n = 15) based on their MR acquisition dates. In the discovery group, we performed univariate and multivariate regression analyses to establish the multiple regression equation for the prediction of the tumor growth rate using diffusion parameters. The equation obtained with the discovery group was applied to the validation group for the confirmation of the equation's accuracy. After the univariate and multivariate regression analyses in the discovery-group patients, the estimated tumor growth rate equation was established by using the significant parameters of intermediate diffusion coefficient D-2 and slow diffusion coefficient D-3 obtained by the tri-exponential model. The discovery group's correlation coefficient between the estimated and directly measured tumor growth rates was 0.74. In the validation group, the correlation coefficient (r = 0.66) and intra-class correlation coefficient (0.65) between the estimated and directly measured tumor growth rates were respectively good. In conclusion, advanced DWI model parameters can be a predictor for determining HNSCC patients' tumor growth rate.

Advanced diffusion models in head and neck squamous cell carcinoma patients: Goodness of fit, relationships among diffusion parameters and comparison with dynamic contrast-enhanced perfusion
Noriyuki Fujima, Tomohiro Sakashita, Akihiro Homma, Yukie Shimizu, Atsushi Yoshida, Taisuke Harada, Khin Khin Tha, Kohsuke Kudo, Hiroki Shirato
MAGNETIC RESONANCE IMAGING, 36, 16, 23, ELSEVIER SCIENCE INC, 2017年02月, ［査読有り］
英語, 研究論文（学術雑誌）, Purpose: We assessed advanced fitting models of diffusion weighted imaging (DWI) in head/neck squamous cell carcinoma (HNSCC) patients to determine the best goodness of fit and correlations among diffusion parameters. We compared these results with those of dynamic contrast-enhanced (DCE) perfusion parameters.
Materials and methods: We retrospectively evaluated 32 HNSCC patients (12 sinonasal, 20 pharynx/oral cavity). The DWI acquisition used single-shot spin-echo echo-planar imaging (EPI) with 12 b-values (0 - 2000). We calculated 14 DWI parameters using mono-exponential, bi-exponential, and tri-exponential models, stretched exponential model (SEM) and diffusion kurtosis imaging (DKI) models. We compared each model's goodness of fit using the residual sum of squares (RSS), Akaike Information Criterion (AIC) and Bayesian information criterion (BIC) value. We determined the correlation between each pair of DWI parameters and between each DWI parameter and DCE perfusion parameter.
Results: The tri-exponential fit's RSS, AIC and BIC values were significantly smaller than those for bi-exponential fit. The RSS, AIC and BIC values of the SEM fit and DKI fit were significantly smaller than mono-exponential model. Significant correlations were observed in 30 pairs (sinonasal cavity) and 31 (sinonasal cavity group) among 91 DWI parameter combinations. Significant correlations were also observed in nine pairs (both sinonasal cavity and pharynx/oral cavity group) among 64 DWI/DCE perfusion parameter pairs, in particular, high positive correlations between the tri-exponential model's intermediate diffusion fraction (f(2)) and the volume of the extracellular extravascular space per unit volume of tissue (v(e)) were observed in both patient groups.
Conclusion: We identified several correlations between DWI parameters by advanced fitting models and correlations between DWI and DCE parameters. These will help determine HNSCC patients' detailed tissue structures. (C) 2016 Elsevier Inc. All rights reserved.

Breath-holding during the Calibration Scan Improves the Reproducibility of Parallel Transmission at 7T for Human Brain
Taisuke Harada, Kohsuke Kudo, Ikuko Uwano, Fumio Yamashita, Hiroyuki Kameda, Tsuyoshi Matsuda, Makoto Sasaki, Hiroki Shirato
MAGNETIC RESONANCE IN MEDICAL SCIENCES, 16, 1, 23, 31, JPN SOC MAGNETIC RESONANCE IN MEDICINE, 2017年, ［査読有り］
英語, 研究論文（学術雑誌）, Purpose: The B0 and B1+ maps required for calculation of the radiofrequency (RF) pulse of parallel transmission (pTx) are obtained in calibration scans; however, they may be affected by respiratory motion. We aimed to compare the reproducibility of B0 and B1+ maps and gradient echo (GRE) images of the brain scanned with pTx at 7T between free-breathing (FB) and breath-holding (BH) conditions during the calibration scan.
Methods: Nine healthy volunteers were scanned by 7T MRI using a two-channel quadrature head coil. In the pTx calibration scans performed with FB and BH, the B0 map was obtained from two different TE images and the B1+ map was calculated by the Bloch-Siegert method. A GRE image (gradient-recalled acquisition in steady state) was also obtained with RF shimming and RF design of pTx with spoke method, as well as quadrature transmission (qTx). All the scans were repeated over five sessions. The reproducibility of the B0 and B1+ maps and GRE image was evaluated with region-of-interest measurements using inter-session standard deviation (SD) and coefficient of variation (CV) values. Intensity homogeneity of GRE images was also assessed with in-plane CV.
Results: Inter-session SDs of B0 and B1+ maps were significantly smaller in BH (P < 0.01). Inter-session CVs of GRE images were significantly smaller in qTx than BH and FB (P < 0.01, both); however, the CVs of BH were significantly smaller (P < 0.01). In-plane CVs of FB and BH with RF shimming were not significantly different with qTx; however, CVs of FB and BH with RF design were significantly smaller than those of qTx (P < 0.05 and P < 0.01, respectively).
Conclusion: BH could improve the reproducibility of B0 and B1+ maps in pTx calibration scans and GRE images. These results might facilitate the development of pTx in human brain at 7T.

定量的磁化率マッピングで脳の構造と酸素代謝をみる　　　　　　　　　　　　　　　
工藤 與亮, 藤間 憲幸, Khin Khin Tha, 清水 幸衣, 原田 太以佑, 吉田 篤司
臨床神経学, 56, Suppl., S62, S62, (一社)日本神経学会, 2016年12月
日本語

Utility of noncontrast-enhanced time-resolved four-dimensional MR angiography with a vessel-selective technique for intracranial arteriovenous malformations
Noriyuki Fujima, Toshiya Osanai, Yukie Shimizu, Atsushi Yoshida, Taisuke Harada, Naoki Nakayama, Kohsuke Kudo, Kiyohiro Houkin, Hiroki Shirato
JOURNAL OF MAGNETIC RESONANCE IMAGING, 44, 4, 834, 845, WILEY-BLACKWELL, 2016年10月, ［査読有り］
英語, 研究論文（学術雑誌）, PurposeTo evaluate the utility of a vessel-selective four-dimensional (4D) magnetic resonance angiography (MRA) technique for the evaluation of intracranial arteriovenous malformations (AVMs).
Materials and MethodsTwelve AVM patients were evaluated retrospectively. Time-of-flight (TOF) MRA, nonvessel-selective 4D-MRA (NS-4D-MRA), and vessel-selective 4D-MRA (VS-4D-MRA) were performed using a 3T MR unit in all patients, and used to identify feeding arteries and draining veins and measure nidus size. The diagnostic accuracy of the three techniques was compared using digital subtraction angiography (DSA). If a multifeeder was observed, the percentage of blood flow of each feeding artery to the entire nidus was evaluated and compared to the DSA findings using the error value, defined as the degree of overestimation of the blood flow. All imaging findings were assessed by two neuroradiologists.
ResultsIn both raters, the detectability of feeding arteries by VS-4D-MRA (12 and 11 patients) was significantly higher than those of TOF-MRA (7 and 6 patients) and NS-4D-MRA (8 and 7 patients) (P < 0.016). The detectability of drainer veins by TOF-MRA (10 and 10 patients) was significantly higher than that of VS-4D-MRA (7 and 6 patients). In the percentage of the blood flow of each feed artery to the entire nidus, the DSA findings (error value; 27.15.7) indicated overestimations of the blood flow compared to the VS-4D-MRA (error value; 7.1 +/- 3.9) (P < 0.001).
ConclusionVS-4D-MRA was shown to be a useful technique for the evaluation of intracranial AVMs, especially for detecting feed arteries and estimating details of the nidus structure. J. MAGN. RESON. IMAGING 2016;44:834-845.

Intracranial Plaque Characterization in Patients with Acute Ischemic Stroke Using Pre- and Post-Contrast Three-Dimensional Magnetic Resonance Vessel Wall Imaging
Tatsunori Natori, Makoto Sasaki, Mitsuharu Miyoshi, Kohei Ito, Hideki Ohba, Haruna Miyazawa, Shinsuke Narumi, Hiroyuki Kabasawa, Taisuke Harada, Yasuo Terayama
JOURNAL OF STROKE & CEREBROVASCULAR DISEASES, 25, 6, 1425, 1430, ELSEVIER SCIENCE BV, 2016年06月, ［査読有り］
英語, 研究論文（学術雑誌）, Background: Magnetic resonance vessel wall imaging (VWI) techniques have been developed to assess atherosclerotic plaques in intracranial arteries, which are a cardinal cause of ischemic stroke. However, the clinical roles of plaque-related vulnerability and inflammation remain unclear. Hence, we evaluated plaque characteristics using VWI of the proximal middle cerebral artery (M1) in patients with acute ischemic stroke. Methods: We prospectively examined 30 consecutive patients with acute noncardioembolic stroke in the M1 territory using pre-/postcontrast T1-weighted (T1W) three-dimensional (3D) VWI with a 3-Tesla scanner. The contrast ratio (CR) and contrast enhancement of the plaques were measured bilaterally at M1. Results: Plaques were identified in the bilateral M1s of all patients, and no substantial stenosis existed. The M1 plaque CRs ipsilateral to the infarct (46.7%-67.9%) were significantly higher than the plaque CRs on the contralateral side (34.3%-69.4%), particularly in patients with lacunar infarcts (P < .01). In contrast, the occurrence of plaque enhancement was not different between the ipsilateral (20.0%) and contralateral (16.7%) sides. Further, the CRs in the nonlacunar group were significantly higher than the CRs in the lacunar group (P < .05), whereas enhanced plaques tended to be more frequent in the nonlacunar group, but this difference was not significant (P = .09). Conclusions: T1W 3D-VWI revealed that the signal intensity of M1 plaques was significantly higher in the affected side and in nonlacunar-type infarcts of patients with acute stroke, suggesting that unstable plaques in the M1 can cause stroke events presumably due to atherothrombotic mechanisms. (C) 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Detection of changes in the periaqueductal gray matter of patients with episodic migraine using quantitative diffusion kurtosis imaging: preliminary findings
Kenji Ito, Masako Kudo, Makoto Sasaki, Ayumi Saito, Fumio Yamashita, Taisuke Harada, Suguru Yokosawa, Ikuko Uwano, Hiroyuki Kameda, Yasuo Terayama
NEURORADIOLOGY, 58, 2, 115, 120, SPRINGER, 2016年02月, ［査読有り］
英語, 研究論文（学術雑誌）, The periaqueductal gray matter (PAG) is considered to play an important role in generating migraine, but findings from imaging studies remain unclear. Therefore, we investigated whether diffusion kurtosis imaging (DKI) can detect changes in the PAG of migraine patients.
We obtained source images for DKI from 20 patients with episodic migraine and 20 healthy controls using a 3 T magnetic resonance imaging scanner. Mean kurtosis (MK), fractional anisotropy (FA), and mean diffusivity (MD) maps were generated, and the values of the PAG and other deep gray and white matter structures were automatically measured using an atlas-based region-of-interest analysis. The metrics of these structures were compared between the patients and controls.
The MK and MD values of the PAG were significantly increased in the migraine patients compared with the controls (p < 0.05). The FA values were not significantly different. There were no significant differences in the metrics of the other structures between the patients and controls. The MK values of the PAG were significantly positively correlated with both age and the untreated period in the patient group under univariate analysis (r = 0.53 and 0.56, respectively; p < 0.05) but not multivariate analysis.
DKI detected significant increases in the MK and MD values of the PAG in patients with migraine, which suggests that structural changes in the PAG are associated with the pathophysiological mechanisms of migraine.

Five-point Likert scaling on MRI predicts clinically significant prostate carcinoma.
Taisuke Harada, Takashige Abe, Fumi Kato, Ryuji Matsumoto, Hiromi Fujita, Sachiyo Murai, Naoto Miyajima, Kunihiko Tsuchiya, Satoru Maruyama, Kohsuke Kudo, Nobuo Shinohara
BMC urology, 15, 91, 91, 2015年09月04日, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, BACKGROUND: To clarify the relationship between the probability of prostate cancer scaled using a 5-point Likert system and the biological characteristics of corresponding tumor foci. METHODS: The present study involved 44 patients undergoing 3.0-Tesla multiparametric MRI before laparoscopic radical prostatectomy. Tracing based on pathological and MRI findings was performed. The relationship between the probability of cancer scaled using the 5-point Likert system and the biological characteristics of corresponding tumor foci was evaluated. RESULTS: A total of 102 tumor foci were identified histologically from the 44 specimens. Of the 102 tumors, 55 were assigned a score based on MRI findings (score 1: n = 3; score 2: n = 3; score 3: n = 16; score 4: n = 11 score 5: n = 22), while 47 were not pointed out on MRI. The tracing study revealed that the proportion of >0.5 cm(3) tumors increased according to the upgrade of Likert scores (score 1 or 2: 33%; score 3: 68.8%; score 4 or 5: 90.9%, χ(2) test, p < 0.0001). The proportion with a Gleason score >7 also increased from scale 2 to scale 5 (scale 2: 0%; scale 3: 56.3%; scale 4: 72.7%; 5: 90.9%, χ(2) test, p = 0.0001). On using score 3 or higher as the threshold of cancer detection on MRI, the detection rate markedly improved if the tumor volume exceeded 0.5 cm(3) (<0.2 cm(3): 10.3%; 0.2-0.5 cm(3): 25%; 0.5-1.0 cm(3): 66.7%; 1.0 < cm(3): 92.1%). CONCLUSIONS: Each Likert scale favobably reflected the corresponding tumor's volume and Gleason score. Our observations show that "score 3 or higher" could be a useful threshold to predict clinically significant carcinoma when considering treatment options.

Detection of early changes in the parahippocampal and posterior cingulum bundles during mild cognitive impairment by using high-resolution multi-parametric diffusion tensor imaging
Ito Kenji, Sasaki Makoto, Takahashi Junko, Uwano Ikuko, Yamashita Fumio, Higuchi Satomi, Goodwin Jonathan, Harada Taisuke, Kudo Kohsuke, Terayama Yasuo
PSYCHIATRY RESEARCH-NEUROIMAGING, 231, 3, 346, 352, 2015年03月30日, ［査読有り］

Detection of early changes in the parahippocampal and posterior cingulum bundles during mild cognitive impairment by using high-resolution multi-parametric diffusion tensor imaging.
Kenji Ito, Makoto Sasaki, Junko Takahashi, Ikuko Uwano, Fumio Yamashita, Satomi Higuchi, Jonathan Goodwin, Taisuke Harada, Kohsuke Kudo, Yasuo Terayama
Psychiatry research, 231, 3, 346, 52, 2015年03月30日, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, We aimed to determine alterations occurring in the parahippocampal cingulum bundle (PhC) and posterior cingulum bundle (PoC) in patients with mild cognitive impairment (MCI) through analysis of high-resolution multi-parametric diffusion tensor imaging (DTI). Participants comprised 41 patients with MCI (21 AD converters [MCI-C] and 20 non-converters [MCI-NC]), 20 patients with Alzheimer׳s disease (AD), and 26 healthy elderly subjects who underwent prospective examination with high-resolution DTI. An atlas-based regions-of-interest (ROIs) method calculated fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (DA), and radial diffusivity (DR) in the PhC and PoC. For the PhC, FA values showed significant decreases, and MD and DR values showed significantly increases, in the MCI-C and AD groups compared with the healthy controls, although the MCI-C and MCI-NC groups did not differ significantly in these metrics. Conversely, none of the diffusion metrics for the PoC showed a significant difference among the MCI groups and the control groups, although there were significant differences between the AD group and control groups. High-resolution multi-parametric DTI analysis was able to detect substantial changes in diffusion anisotropy and diffusivity in the PhC of patients with MCI who were destined to convert to AD.

Differentiation among parkinsonisms using quantitative diffusion kurtosis imaging
Kenji Ito, Makoto Sasaki, Chigumi Ohtsuka, Suguru Yokosawa, Taisuke Harada, Ikuko Uwano, Fumio Yamashita, Satomi Higuchi, Yasuo Terayama
NEUROREPORT, 26, 5, 267, 272, LIPPINCOTT WILLIAMS & WILKINS, 2015年03月, ［査読有り］
英語, 研究論文（学術雑誌）, Differential diagnoses among Parkinson's disease (PD), multiple system atrophy (MSA), and progressive supranuclear palsy syndrome (PSPS) are often difficult. Hence, we investigated whether diffusion kurtosis imaging (DKI) could detect pathological changes that occur in these disorders and be used to differentiate between such patients. Fourteen patients (five with PD, four MSA, and five PSPS) and six healthy controls were examined using a 1.5-T scanner. Mean kurtosis (MK), fractional anisotropy, and mean diffusivity maps were generated, and these values of the midbrain tegmentum (MBT) and pontine crossing tract (PCT), as well as MBT/PCT ratios, were obtained. We found no significant differences in MBT and PCT values on DKI maps among the groups. In contrast, MBT/PCT ratios from MK maps were significantly increased in the MSA group and decreased in the PSPS group compared with the other groups. MBT/PCT ratios from mean diffusivity maps showed a significant increase in the PSPS group. Therefore, quantitative DKI analyses, particularly the MBT/PCT ratio from MK maps, can differentiate patients with parkinsonisms. Copyright (C) 2015 Wolters Kluwer Health, Inc. All rights reserved.

Assessment of Sensations Experienced by Subjects during MR Imaging Examination at 7T
Ikuko Uwano, Tsuyoshi Metki, Fusako Sendai, Ryoko Yoshida, Kohsuke Kudo, Fumio Yamashita, Satomi Higuchi, Kenji Ito, Taisuke Harada, Jonathan Goodwin, Akira Ogawa, Makoto Sasaki
MAGNETIC RESONANCE IN MEDICAL SCIENCES, 14, 1, 35, 41, JPN SOC MAGNETIC RESONANCE IN MEDICINE, 2015年, ［査読有り］
英語, 研究論文（学術雑誌）, Purpose: We investigated sensations experienced by a large number of subjects during magnetic resonance (MR) imaging examinations using a 7-tesla scanner and slow table-feed speed.
Methods: After examinations at 7T, 504 of 508 consecutive subjects completed questionnaires using an 11-point scale to rate 14 potential sensations and symptoms during table movement and stationary positioning of the table. We compared scores among the sensations and between table conditions and the mean values of the scores with those reported in previous studies and examined correlations between the scores and subject characteristics.
Results: Vertigo and feelings of curving or leaning in the right or left direction during table movement were experienced frequently and markedly compared to other sensations and sensations experienced when the table was stationary (P < 0.01) and were correlated with subject age and examination time (P < 0.05). However, moderate to severe (scores of 5 to 10) vertigo and a curving/leaning feeling during table movement were noted in only 10.5% (vertigo) and 10.9% (curving/leaning) of subjects, and the mean vertigo score, 1.26, appeared to be substantially lower than that reported in a previous study. Reports of a metallic taste, nausea, and light flashes were significantly rarer and weaker than other sensations (P < 0.05).
Conclusion: Vertigo and feelings of curving during table movement were the most frequent sensations reported during MR imaging examination at 7T. However, the occurrence and severity were low and mild, presumably because of the slow table-feed speed, which suggests that most patients and volunteers found discomfort at 7T acceptable.

Detection of Vessel Wall Lesions in Spontaneous Symptomatic Vertebrobasilar Artery Dissection Using T1-weighted 3-dimensional Imaging
Tatsunori Natori, Makoto Sasaki, Mitsuharu Miyoshi, Hideki Ohba, Mao Yamaguchi Oura, Shinsuke Narumi, Taisuke Harada, Hiroyuki Kabasawa, Yasuo Terayama
JOURNAL OF STROKE & CEREBROVASCULAR DISEASES, 23, 9, 2419, 2424, ELSEVIER SCIENCE BV, 2014年10月, ［査読有り］
英語, 研究論文（学術雑誌）, Background: Spontaneous intracranial vertebrobasilar artery dissection (iVBD) is a cause of ischemic stroke and subarachnoid hemorrhage in young adults that can be detected noninvasively by using multisequence magnetic resonance imaging (MRI). However, MRI findings are sometimes difficult to interpret, and its accuracy tends to be suboptimal, especially during the acute period. Therefore, we investigated whether 3-dimensional (3D) vessel wall imaging (VWI) technique could readily detect iVBD lesions in acute phase patients. Methods: Sixteen consecutive patients with acute ischemic stroke caused by iVBD were prospectively examined with a 1.5-T magnetic resonance scanner. T1-weighted (T1W) 3D-VWI was obtained using a flow-sensitized 3D fast spin-echo technique. In addition, multisequence MRI comprising magnetic resonance angiography (MRA), basiparallel anatomical scanning (BPAS), and axial T1W imaging (T1WI) were also examined. Presence of luminal stenosis, aneurysmal dilatation, intramural high signal, and intimal flap/double lumen of the vertebral and basilar arteries were visually assessed using each technique. Results: On 3D-VWI, luminal stenosis, aneurysmal dilatation, intramural high signal, and intimal flap were observed in 16 (100%), 11 (68.8%), 16 (100%), and 1 (6.3%) patients, respectively. In contrast, on conventional techniques, these findings were observed in 15 (93.8%, MRA with BPAS), 12 (75.0%, MRA with BPAS), 12 (75.0%, T1WI), and 12 (75.0%, MRA) patients, respectively. Conclusions: The T1W 3D-VWI can directly visualize vessel wall iVBD lesions during the acute period of stroke compared with multisequence

Hand-assisted laparoscopic splenectomy for sclerosing angiomatoid nodular transformation of the spleen complicated by chronic disseminated intravascular coagulation: A case report
Tatsuhiko Kakisaka, Toshiya Kamiyama, Hideki Yokoo, Tatsuya Orimo, Kenji Wakayama, Yosuke Tsuruga, Hirofumi Kamachi, Taisuke Harada, Fumi Kato, Yosuke Yamada, Tomoko Mitsuhashi, Akinobu Taketomi
Asian Journal of Endoscopic Surgery, 7, 3, 275, 278, Wiley, 2014年08月, ［査読有り］
研究論文（学術雑誌）

Intensity inhomogeneity correction for magnetic resonance imaging of human brain at 7T
Ikuko Uwano, Kohsuke Kudo, Fumio Yamashita, Jonathan Goodwin, Satomi Higuchi, Kenji Ito, Taisuke Harada, Akira Ogawa, Makoto Sasaki
MEDICAL PHYSICS, 41, 2, 022302, AMER ASSOC PHYSICISTS MEDICINE AMER INST PHYSICS, 2014年02月, ［査読有り］
英語, 研究論文（学術雑誌）, Purpose: To evaluate the performance and efficacy for intensity inhomogeneity correction of various sequences of the human brain in 7T MRI using the extended version of the unified segmentation algorithm.
Materials: Ten healthy volunteers were scanned with four different sequences (2D spin echo [SE], 3D fast SE, 2D fast spoiled gradient echo, and 3D time-of-flight) by using a 7T MRI system. Intensity inhomogeneity correction was performed using the "New Segment" module in SPM8 with four different values (120, 90, 60, and 30 mm) of full width at half maximum (FWHM) in Gaussian smoothness. The uniformity in signals in the entire white matter was evaluated using the coefficient of variation (CV); mean signal intensities between the subcortical and deep white matter were compared, and contrast between subcortical white matter and gray matter was measured. The length of the lenticulostriate (LSA) was measured on maximum intensity projection (MIP) images in the original and corrected images.
Results: In all sequences, the CV decreased as the FWHM value decreased. The differences of mean signal intensities between subcortical and deep white matter also decreased with smaller FWHM values. The contrast between white and gray matter was maintained at all FWHM values. LSA length was significantly greater in corrected MIP than in the original MIP images.
Conclusions: Intensity inhomogeneity in 7T MRI can be successfully corrected using SPM8 for various scan sequences. (C) 2014 American Association of Physicists in Medicine.

放射線科医が触れる死後画像(突然死)中枢神経系領域の死後画像診断-Case review-
池辺洋平, 池辺洋平, 原田太以佑, 原田太以佑, 工藤與亮, 工藤與亮, 臨床画像, 39, 11, 2023年

全身の血栓症・塞栓症を考える 脳静脈血栓症
池辺洋平, 池辺洋平, 原田太以佑, 原田太以佑, 原田太以佑, 工藤與亮, 工藤與亮, 工藤與亮, 画像診断, 43, 14, 2023年

Dynamic心筋CT perfusionに対するfour-dimensional similarity filterの画質改善効果の検討
常田慧徳, 常田慧徳, 真鍋徳子, 亀田浩之, 原田太以佑, 加藤扶美, 工藤與亮, 日本心血管画像動態学会プログラム・抄録集, 30th, 2020年

画像診断と病理 形成異常小脳神経節膠腫(Lhermitte-Duclos病)
星野豊, 亀田浩之, 原田太以佑, 工藤與亮, 伊師雪友, 三橋智子, 杉野弘和, 画像診断, 40, 13, 2020年

IVW-MRIが治療効果判定に有用であった中枢神経限局性血管炎　　　　　　　　　　　　　　　
井上 知彦, 水島 慶一, 工藤 彰彦, 佐藤 翔紀, 佐藤 智香, 長沼 亮滋, 上床 尚, 白井 慎一, 高橋 育子, 松島 理明, 矢部 一郎, 原田 太以佑, 工藤 與亮, 佐々木 秀直, 臨床神経学, 58, Suppl., S456, S456, 2018年12月
(一社)日本神経学会, 日本語

多系統萎縮症におけるプロトン密度強調画像を用いた小脳の信号強度の検討　　　　　　　　　　　　　　　
山口 晃典, 原田 太以佑, 松島 理明, 矢部 一郎, 佐々木 秀直, 工藤 與亮, 臨床神経学, 58, Suppl., S241, S241, 2018年12月
(一社)日本神経学会, 日本語

IVW-MRIが治療効果判定に有用であった中枢神経限局性血管炎　　　　　　　　　　　　　　　
井上 知彦, 水島 慶一, 工藤 彰彦, 佐藤 翔紀, 佐藤 智香, 長沼 亮滋, 上床 尚, 白井 慎一, 高橋 育子, 松島 理明, 矢部 一郎, 原田 太以佑, 工藤 與亮, 佐々木 秀直, 臨床神経学, 58, Suppl., S456, S456, 2018年12月
(一社)日本神経学会, 日本語

腹臥位での腰仙椎MRIが診断に有用であった脊髄係留症候群の1例　　　　　　　　　　　　　　　
水島 慶一, 佐藤 翔紀, 工藤 彰彦, 佐藤 智香, 長沼 亮滋, 上床 尚, 白井 慎一, 高橋 育子, 松島 理明, 矢部 一郎, 原田 太以佑, 工藤 與亮, 濱内 祝嗣, 関 俊隆, 佐々木 秀直, 臨床神経学, 58, 5, 358, 358, 2018年05月
(一社)日本神経学会, 日本語

腹臥位での腰仙椎MRIが診断に有用であった脊髄係留症候群の1例　　　　　　　　　　　　　　　
水島 慶一, 佐藤 翔紀, 工藤 彰彦, 佐藤 智香, 長沼 亮滋, 上床 尚, 白井 慎一, 高橋 育子, 松島 理明, 矢部 一郎, 原田 太以佑, 工藤 與亮, 濱内 祝嗣, 関 俊隆, 佐々木 秀直, 臨床神経学, 58, 5, 358, 358, 2018年05月
(一社)日本神経学会, 日本語

腹臥位での腰仙椎MRIが診断に有用であった脊髄係留症候群の1例
水島慶一, 佐藤翔紀, 工藤彰彦, 佐藤智香, 長沼亮滋, 上床尚, 白井慎一, 高橋育子, 松島理明, 矢部一郎, 原田太以佑, 工藤與亮, 浜内祝嗣, 関俊隆, 佐々木秀直, 臨床神経学(Web), 58, 5, 2018年

成人発症のAlexander病の1例　　　　　　　　　　　　　　　
阿部 恵, 西村 洋昭, 長沼 亮滋, 白井 慎一, 高橋 育子, 松島 理明, 加納 崇裕, 矢部 一郎, 原田 太以佑, 藤間 憲幸, 工藤 與亮, 吉田 誠克, 佐々木 秀直, 臨床神経学, 57, 6, 322, 322, 2017年06月
(一社)日本神経学会, 日本語

成人発症のAlexander病の1例
阿部恵, 西村洋昭, 長沼亮滋, 白井慎一, 高橋育子, 松島理明, 加納崇裕, 矢部一郎, 原田太以佑, 藤間憲幸, 工藤與亮, 吉田誠克, 佐々木秀直, 臨床神経学(Web), 57, 6, 2017年

臨床 QSMの現状と将来について (ROUTINE CLINICAL MRI 2017 BOOK)
原田 太以佑, 工藤 與亮, 映像情報medical : a monthly journal of medical imaging and information, 48, 14, 68, 76, 2016年12月
産業開発機構映像情報メディカル編集部, 日本語

7 Tesla MRAによる急性期脳梗塞における外側線条体動脈の評価　　　　　　　　　　　　　　　
原田 太以佑, 佐々木 真理, 山下 典生, 樋口 さとみ, 上野 育子, 伊藤 賢司, Goodwin Jonathan, 大庭 英樹, 寺山 靖夫, Japanese Journal of Radiology, 34, Suppl., 2, 2, 2016年02月
(公社)日本医学放射線学会, 日本語

7Tesla高解像度MRAによる前脈絡叢動脈穿通枝の描出能の検討　　　　　　　　　　　　　　　
原田 太以佑, 佐々木 真理, 山下 典生, 樋口 さとみ, 上野 育子, 伊藤 賢司, Goodwin Jonathan, 大庭 英樹, 寺山 靖夫, Japanese Journal of Radiology, 34, Suppl., 12, 12, 2016年02月
(公社)日本医学放射線学会, 日本語

3-Tesla MRIの前立腺癌検出能に関する検討　　　　　　　　　　　　　　　
安部 崇重, 原田 太以佑, 加藤 扶美, 松本 隆児, 藤田 裕美, 丸山 覚, 土屋 邦彦, 宮島 直人, 篠原 信雄, 日本泌尿器科学会総会, 103回, 575, 575, 2015年04月
(一社)日本泌尿器科学会総会事務局, 日本語

High Resolution Images of Perforating Arteries With 7T MRA in Acute Subcortical Infarction
Hideki Ohba, Taisuke Harada, Makoto Sasaki, Kazumasa Ohura, Tatsunori Natori, Shinsuke Narumi, Mao Ohura, Tadayoshi Kato, Yasuo Terayama, STROKE, 46, 2015年02月
LIPPINCOTT WILLIAMS & WILKINS, 英語, 研究発表ペーパー・要旨（国際会議）

橋前槽に膜形成を認めたBlake's pouch cystの1例　　　　　　　　　　　　　　　
原田 太以佑, 佐々木 真理, 山下 典生, 樋口 さとみ, Goodwin Jonathan, 上野 育子, 伊藤 賢司, 吉田 浩二, 佐藤 由衣子, 南波 孝昌, 西川 泰正, 小笠原 邦昭, Japanese Journal of Radiology, 33, Suppl., 8, 8, 2015年02月
(公社)日本医学放射線学会, 日本語

7-Tesla高解像度MRAにおけるlong insular arteryの描出能の検討　　　　　　　　　　　　　　　
原田 太以佑, 佐々木 真理, 山下 典生, 樋口 さとみ, Goodwin Jonathan, 上野 育子, 伊藤 賢司, 佐藤 由衣子, 南波 孝昌, 別府 高明, 小笠原 邦昭, Japanese Journal of Radiology, 33, Suppl., 1, 1, 2015年02月
(公社)日本医学放射線学会, 日本語

拡散尖度画像と定量的磁化画像を用いたパーキンソン症候群の早期鑑別診断　　　　　　　　　　　　　　　
伊藤 賢司, 佐々木 真理, 大塚 千久美, 横沢 俊, 佐藤 良太, 尾藤 良孝, 原田 太以佑, 上野 育子, 山下 典生, 樋口 さとみ, Jonathan Goodwin, 寺山 靖夫, 日本磁気共鳴医学会雑誌, 35, 1, 26, 26, 2015年02月
(一社)日本磁気共鳴医学会, 日本語

7Tesla高解像度MRAによる前脈絡叢動脈分枝の検討
原田太以佑, 原田太以佑, 佐々木真理, 伊藤賢司, 上野育子, 山下典生, 樋口さとみ, 大庭英樹, 松田豪, 椛沢宏之, 寺山靖夫, 日本神経放射線学会プログラム・抄録集, 44th, 2015年

拡散尖度画像を用いた片頭痛患者における中脳水道周囲灰白質の評価
伊藤賢司, 佐々木真理, 工藤雅子, 齋藤あゆみ, 横沢俊, 原田太以佑, 上野育子, 山下典生, 樋口さとみ, 寺山靖夫, 日本神経放射線学会プログラム・抄録集, 44th, 2015年

3テスラ乳腺MRIにおけるSSGR(slice selection gradient reversal)法を用いた拡散強調像
加藤扶美, 真鍋徳子, 三村理恵, 原田太以佑, 寺江聡, 藤原太郎, 杉森博行, 細田充主, 田口和典, 山下啓子, 白土博樹, Jpn J Radiol, 32, Supplement, 10, 2014年02月25日
日本語

脾のSANT(Sclerosing Angiomatoid Nodular Transformation)の2例
原田太以佑, 加藤扶美, 菊池穏香, 三村理恵, 真鍋徳子, 小野寺祐也, 寺江聡, 柿坂達彦, 若山顕治, 横尾英樹, 神山俊哉, 高桑恵美, 山田洋介, 三橋智子, 白土博樹, Jpn J Radiol, 32, Supplement, 12, 2014年02月25日
日本語

拡散尖度画像を用いたパーキンソン症候群の早期鑑別診断
伊藤賢司, 佐々木真理, 大塚千久美, 横沢俊, 尾藤良孝, 上野育子, 山下典生, 樋口さとみ, GOODWIN Jonathan, 原田太以佑, 寺山靖夫, 日本神経放射線学会プログラム・抄録集, 43rd, 2014年

臨床画像 Vol.36 No.10　　　　　　　　　　　　　　　
清水幸恵, 原田太以佑, 人工透析患者の中枢神経病変
メジカルビュー社, 2020年09月

画像診断 Vol.40 No.10　　　　　　　　　　　　　　　
原田太以佑, 時系列から学ぶ中枢神経疾患の画像診断-MR Retroscopy -
学研メディカル秀潤社, 2020年09月, ［分担執筆］

画像診断 2020年6月　　　　　　　　　　　　　　　
原田太以佑, 免疫チェックポイント療法による合併症
学研メディカル秀潤社, 2020年06月, ［分担執筆］

Radfan2020年4月号　　　　　　　　　　　　　　　
原田太以佑, 2020年におけるMRIのトレンド
株式会社メディカルアイ, 2020年04月, ［分担執筆］

臨床画像 Vol.36 No.4　　　　　　　　　　　　　　　
原田太以佑, 中枢神経領域の治療に関連する画像所見
メジカルビュー社, 2020年03月, ［分担執筆］

RadFan2019年9月号　　　　　　　　　　　　　　　
原田太以佑, 工藤 與亮, 酸素の安定同位体17O標識水による脳血流定量化
株式会社メディカルアイ, 2019年09月, ［分担執筆］

INNERVISION 2019年2月号　　　　　　　　　　　　　　　
原田太以佑, 受賞報告
インナービジョン, 2019年02月

BRAIN and NERVE Vol.70 No.12　　　　　　　　　　　　　　　
原田太以佑, 藤間憲幸, 工藤與亮, 主訴に沿う 俯瞰し収束する画像診断の目、ふるえる
医学書院, 2018年12月, ［分担執筆］

インナービジョン2018年9月号　　　　　　　　　　　　　　　
原田太以佑, 藤間憲幸, 工藤 與亮, 頭部領域におけるMRI の新技術と臨床応用 定量的磁化率マッピングの臨床応用
インナービジョン, 2018年08月, ［分担執筆］

すぐ役立つ救急のCT・MRI
井田, 正博, 高木, 亮(放射線), 藤田, 安彦, 「脳挫傷」pg326-327、「出血性脳挫」傷pg328-329、「DTICH」 pg330-331、「びまん性脳腫脹・びまん性軸索損傷」pg80-81、「慢性硬膜下血腫」pg82-83
学研メディカル秀潤社, 2018年03月, 9784780909401, 395p, 日本語, ［分担執筆］

臨床画像 Vol.33 No.10　　　　　　　　　　　　　　　
原田太以佑, 薬物治療に起因する諸病態の画像所見 中枢神経
メジカルビュー社, 2017年11月, ［分担執筆］

ROUTINE CLINICALMRI 2017(映像情報Medical 増刊号)　　　　　　　　　　　　　　　
原田太以佑、工藤 與亮, 定量的磁化率マッピングの基礎と応用, pg68-75
映像情報メディカル, 2016年12月, ［分担執筆］

認知症MRI～形態診断を越えて～　　　　　　　　　　　　　　　
原田太以佑
第56回日本医学放射線学会秋季臨床大会, 2020年, シンポジウム・ワークショップパネル（指名）
［招待講演］

Quantitative susceptibility mapping: Basics and Clinical applications　　　　　　　　　　　　　　　
Taisuke Harada, Kohsuke Kudo, Akinori Yamaguchi, Masato Yoshikawa, Youhei Ikebe, Ryota Sato, Toru Shirai, Yoshitaka Bito, Ikuko Uwano, Mari Miyata
RSNA (The Radiological Society of North America), 2020年, ポスター発表

CNS Complications of Precision Cancer Therapies　　　　　　　　　　　　　　　
Taisuke Harada
AIMS neuroimaging, 2019年, 公開講演，セミナー，チュートリアル，講習，講義等
［招待講演］

後頭蓋窩腫瘍の画像所見　　　　　　　　　　　　　　　
原田太以佑
第55回日本医学放射線学会秋期臨床大会, 2019年, 公開講演，セミナー，チュートリアル，講習，講義等
［招待講演］

治療に伴う中枢神経画像所見　　　　　　　　　　　　　　　
原田太以佑
第47回日本磁気共鳴医学会大会, 2019年, 公開講演，セミナー，チュートリアル，講習，講義等
［招待講演］

Imaging findings in medication-induced changes of the central nervous system: what radiologists should know　　　　　　　　　　　　　　　
Taisuke Harada, Kohsuke Kudo, Noriyuki Fujima, Hiroyuki Kameda, Khin Khin Tha, Yukunori Korogi, Maki Umino
RSNA (The Radiological Society of North America), 2018年, ポスター発表

Comparison of reconstruction algorithms for quantitative susceptibility mapping in the upper abdomen　　　　　　　　　　　　　　　
Taisuke Harada, Kohsuke Kudo, Ryota Sato, Masato Yoshikawa, Satoshi Yabusaki, Toru Shirai, Yoshitaka Bito
ISMRM (International Society of Magnetic Resonance in Medicine) 25th Annual Meeting and Exhibition, 2018年, ポスター発表

Imaging medication-related changes in the central nervous system　　　　　　　　　　　　　　　
Taisuke Harada, Kohsuke Kudo, Yukie Shimizu, Noriyuki Fujima, Tha Khin Khin
SNR (XI Symposium Neuroradiologicum), 2018年, 口頭発表（一般）

17O標識水の第1相臨床試験：安全性および脳血流MRIの実現可能性に関する検討　　　　　　　　　　　　　　　
原田太以佑, 工藤與亮, 亀田浩之, 佐藤良太, 白猪亨, 尾藤良孝, 藤間憲幸, 常田慧徳, 野川敏史, 前田憲一郎, 林宏至, 佐々木真理
第46回日本磁気共鳴医学会大会, 2018年, ポスター発表

上腹部定量的磁化率マッピングの解析アルゴリズムに関する検討　　　　　　　　　　　　　　　
原田太以佑, 工藤與亮, 佐藤良太, 吉川仁人, 薮崎哲史, 白猪亨, 尾藤良孝
第45回日本磁気共鳴医学会大会, 2017年, ポスター発表

Improvement of the Reproducibility of Parallel Transmission at 7T by Breath-Holding During the Calibration Scan　　　　　　　　　　　　　　　
Taisuke Harada, Kohsuke Kudo, Ikuko Uwano, Fumio Yamashita, Hiroyuki Kameda, Tsuyoshi Matsuda, Makoto Sasaki, Hiroki Shirato
ISMRM(International Society of Magnetic Resonance in Medicine) 24th Annual Meeting and Exhibition, 2016年, ポスター発表

Improved Homogeneity of B1+ and Signal Intensity at 7T Using a Parallel Transmission on Human Volunteers　　　　　　　　　　　　　　　
Taisuke Harada, Kohsuke Kudo, Ikuko Uwano, Fumio Yamashita, Hiroyuki Kameda, Tsuyoshi Matsuda, Makoto Sasaki, Hiroki Shirato
ISMRM(International Society of Magnetic Resonance in Medicine) 24th Annual Meeting and Exhibition, 2016年, ポスター発表

上腹部QSM(Quantitative susceptibility mapping)の基礎検討　　　　　　　　　　　　　　　
原田太以佑, 薮崎哲史, 三村理恵, 加藤扶美, 工藤與亮, 佐藤良太, 白猪亨, 尾藤良孝
第135回日本医学放射線学会北日本地方会, 2016年, 口頭発表（一般）

7Tesla高解像度MRAによる前脈絡叢動脈穿通枝の描出能の検討　　　　　　　　　　　　　　　
原田太以佑, 佐々木真理, 大庭英樹, 上野育子, 伊藤賢司, 山下典生, 樋口さとみ, 寺山靖夫
第40回日本脳卒中学会総会, 2015年, 口頭発表（一般）

7Tesla高解像度MRAによる前脈絡叢動脈分枝の検討　　　　　　　　　　　　　　　
原田太以佑, 佐々木真理, 伊藤賢司, 上野育子, 山下典生, 樋口さとみ, 大庭英樹, 松田豪, 椛沢宏之, 寺山靖夫
第44回日本神経放射線学会, 2015年, 口頭発表（一般）

High-Resolution MR Angiography at 7T: Detection of Perforating Arteries of the Anterior Communicating and Distal Middle Cerebral Arteries　　　　　　　　　　　　　　　
Taisuke Harada, Yuiko Sato, Takamasa Nanba, Takahiro Kouji, Takaaki Beppu, Tsuyoshi Matsuda, Hiroyuki Kabasawa, Fumio Yamashita, Ikuko Uwano, Kohsuke Kudo, Kuniaki Ogasawara, Makoto Sasaki
ISMRM(International Society of Magnetic Resonance in Medicine) 22th Annual Meeting and Exhibition, 2014年, ポスター発表

7Tesla高解像度MRAによる前脈絡叢動脈穿通枝の描出能の検討　　　　　　　　　　　　　　　
原田太以佑, 佐々木真理, 大庭英樹, 上野育子, 伊藤賢司, 山下典生, 樋口さとみ, Jonathan Goodwin, 寺山靖夫
第131回日本医学放射線学会北日本地方会, 2014年, 口頭発表（一般）

7 Tesla高解像度MRAによる急性期脳梗塞における外側線条体動脈の変化　　　　　　　　　　　　　　　
原田太以佑, 佐々木真理, 大庭英樹, 上野育子, 伊藤賢司, 山下典生, 樋口さとみ, Jonathan Goodwin, 松田豪, 椛沢宏之, 寺山靖夫
第42回日本磁気共鳴医学会大会, 2014年, 口頭発表（一般）

Detection of perforating branches of the anterior communicating artery by using high-resolution MRA at 7T.　　　　　　　　　　　　　　　
原田太以佑, 佐藤由衣子, 南波孝昌, 別府高明, 松田豪, 椛沢宏之, 山下典生, 樋口さとみ, Jonathan Goodwin, 上野育子, 伊藤賢司, 工藤與亮, 小笠原邦昭, 佐々木真理
第43回日本神経放射線学会, 2014年, 口頭発表（一般）

7 Tesla高解像度MRAにおけるlong insular arteryの描出能の検討　　　　　　　　　　　　　　　
原田太以佑, 佐藤由衣子, 南波孝昌, 別府高明, 松田豪, 椛沢宏之, 山下典生, 樋口さとみ, Jonathan Goodwin, 上野育子, 伊藤賢司, 工藤與亮, 小笠原邦昭, 佐々木真理
第41回日本磁気共鳴医学会大会, 2013年, 口頭発表（一般）

7-Tesla高解像度MRAにおけるlong insular arteryの描出能の検討　　　　　　　　　　　　　　　
原田太以佑, 佐々木真理, 山下典生, 樋口さとみ, Jonathan Goodwin, 上野育子, 伊藤賢司, 佐藤由衣子, 南波孝昌, 別府高明, 小笠原邦昭
第128回日本医学放射線学会北日本地方会, 2013年, 口頭発表（一般）

脾のSANT(Sclerosing angiomatoid nodular transformation)の2例　　　　　　　　　　　　　　　
原田太以佑, 加藤扶美, 菊池穏香, 三村理恵, 真鍋徳子, 小野寺祐也, 寺江聡, 柿坂達彦, 若山顕治, 横尾英樹, 神山俊哉, 高桑恵美, 山田洋介, 三橋智子, 白土博樹
第127回日本医学放射線学会北日本地方会, 2012年

回収中に断裂を来したCV カテーテル離断遺残の1 例　　　　　　　　　　　　　　　
原田太以佑, 臼渕浩明, 小林健太郎, 西岡典子, 石黒絵里, 宮崎知保子
第57回北海道血管造影Interventional Radiology 研究会, 2012年

Improved Homogeneity of B1+ and Signal Intensity at 7T Using a Parallel Transmission on Human Volunteers　　　　　　　　　　　　　　　
原田太以佑, 工藤與亮, 上野育子, 山下典生, 亀田浩之, 松田豪, 佐々木真理, 白土博樹
第72回日本医学放射線学会総会, 2011年, 口頭発表（一般）

妊婦の腎血管筋脂肪腫破裂に対してTAE を行った1 例　　　　　　　　　　　　　　　
原田太以佑, 臼渕 浩明, 藪崎 哲史, 宮崎知保子, 奥山 和彦, 関 利盛
第55回北海道血管造影Interventional Radiology 研究会, 2011年

99mTc-DTPA dynamic SPECTの有用性の検討　　　　　　　　　　　　　　　
原田太以佑, 宮崎知保子, 藪崎哲史, 嘉成悠介, 臼渕浩明, 望月端吾, 関利盛
第 25 回日本核医学会北海道地方会, 2010年

7 Tesla MRAによる急性期脳梗塞における外側線条体動脈の評価　　　　　　　　　　　　　　　
原田太以佑, 佐々木真理, 山下典生, 樋口さとみ, 上野育子, 伊藤賢司, Jonathan Goodwin, 大庭英樹, 寺山靖夫
第130回日本医学放射線学会地方会, 2008年, 口頭発表（一般）

Quantitative measurement of susceptibility/R2* values of SPIO-labeled bone marrow stromal cells in gel phantom　　　　　　　　　　　　　　　
原田太以佑, 工藤與亮, 白猪亨, 尾藤良孝, 七戸秀夫, Tan Chengbo, Wang Ziefeng, 宝金清博, 白土博樹
第44回日本磁気共鳴学会, 2007年, 口頭発表（一般）

放射線診断　　　　　　　　　　　　　　　
北海道大学医学部
2019年04月 - 現在

死因究明　　　　　　　　　　　　　　　
北海道大学医学部
2020年10月

2018年 - 現在
北米放射線学会　　　　　　　　　　　　　　　

2015年04月 - 現在
ISMRM　　　　　　　　　　　　　　　

2014年04月 - 現在
神経放射線学会　　　　　　　　　　　　　　　

2012年 - 現在
日本磁気共鳴医学会　　　　　　　　　　　　　　　

2010年04月 - 現在
日本核医学学会　　　　　　　　　　　　　　　

2008年04月 - 現在
日本医学放射線学会　　　　　　　　　　　　　　　

脳内鉄沈着解析によるアルツハイマー病の病態解明
科学研究費助成事業
2021年04月01日 - 2024年03月31日
原田 太以佑
①正常個体およびADモデルマウス・ラットの経時的な鉄定量解析[2021-2022年度]：疾患モデル動物の脳内鉄沈着解析のために、本年度では最適な撮像条件や解析条件の確立が重要である。そのためにMRI撮像およびQSMの再構成条件について検討を行っているが、実験動物の脳という対象物が小さい場合に解析領域の自動抽出が困難であり、手動で解析領域を決定して再構成をするアルゴリズムを構築している。撮像条件および解析条件に関しては、周囲の空気などによる位相の変動から影響を受けたアーチファクトが強く認められており、できる限りアーチファクトを小さくし、定量解析が可能な撮像条件の探索を行っている。マウスによる撮像条件や解析条件が決定でき次第、疾患モデル動物とwild typeの定量的な評価を行えるように縦断的な撮像および計測を開始していく予定である。
日本学術振興会, 若手研究, 北海道大学, 21K15757