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小川 正樹オガワ マサキ

所属部署医学研究科放射線医学分野
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Last Updated :2019/06/01

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  • Utility of the variable flip angle 3D fast-spin echo (isoFSE) sequence on 3T MR for diagnosing vertebrobasilar artery dissection, Masaki Ogawa, Shingo Omata, Hirohito Kan, Nobuyuki Arai, Marehiko Asai, Misugi Urano, Yuta Shibamoto, Radiological Physics and Technology, 11,   2018年06月01日, © 2018, Japanese Society of Radiological Technology and Japan Society of Medical Physics. We aimed to investigate the utility of the isoFSE sequence, one of the variable flip angle 3D fast-spin echo sequences, on 3T-MR for displaying vessel walls and diagnosing vertebrobasilar artery dissection (VAD). We retrospectively evaluated 12 initial and 28 follow-up images from 12 patients diagnosed with either intracranial VAD or carotid artery dissection. The image quality for displaying the vessel wall was scored using a five-point scale (1 poor, 5 excellent) on initial T1-weighted isoFSE images for each region of the arteries. The intracranial artery dissection findings assessed at time points after onset were evaluated on initial and follow-up T1/T2-weighted isoFSE images. For small arteries, including the anterior/posterior inferior cerebellar artery, similar high scores were obtained on both unenhanced and contrast-enhanced T1-weighted isoFSE images (average: 4.7–5.0, p > 0.2). On unenhanced images, dissected vertebral arteries showed significantly lower scores than non-dissected vertebral arteries for both readers (p = 0.017 and 0.015, respectively), but the scores were high (3.9 and 4.0, respectively). Definitive findings of VAD were observed on the initial images except in one case. For all cases, definitive findings were seen on at least one of the initial or follow-up images. Temporal changes in the findings could be observed for all cases. In conclusion, we showed favorable wall visualization on T1-weighted isoFSE images and the utility of follow-up imaging using unenhanced-T1/T2-weighted and contrast-enhanced T1-weighted isoFSE sequences with acceptable scan times, which could promote the regular use of 3D black-blood vessel wall imaging.
  • 今月の症例 画像診断 舌扁桃肥大(lingual tonsillar hypertrophy), 中川 基生, 中山 明峰, 浦野 みすぎ, 小川 正樹, 渡辺 安曇, 小澤 良之, 下平 政史, 芝本 雄太, 宮嵜 治, 小児科臨床, 71, (6) 1025 - 1028,   2018年06月
  • Differentiation between malignant and benign musculoskeletal tumors using diffusion kurtosis imaging, Masaki Ogawa, Hirohito Kan, Nobuyuki Arai, Taro Murai, Yoshihiko Manabe, Yusuke Sawada, Yuta Shibamoto, Skeletal Radiology,   2018年05月09日, © 2018 ISS Objective: The purpose of this study was to evaluate differences in parameters of diffusion kurtosis imaging (DKI) and minimum apparent diffusion coefficient (ADCmin) between benign and malignant musculoskeletal tumors. Materials and methods: In this prospective study, 43 patients were scanned using a DKI protocol on a 3-T MR scanner. Eligibility criteria were: non-fatty, non-cystic soft tissue or osteolytic tumors; > 2 cm; location in the retroperitoneum, pelvis, leg, or neck; and no prior treatment. They were clinically or histologically diagnosed as benign (n = 27) or malignant (n = 16). In the DKI protocol, diffusion-weighted imaging was performed using four b values (0-2000 s/mm2) and 21 diffusion directions. Mean kurtosis (MK) values were calculated on the MR console. A recently developed software application enabling reliable calculation was used for DKI analysis. Results: MK showed a strong correction with ADCmin(Spearman’s rs = 0.95). Both MK and ADCminvalues differed between benign and malignant tumors (p < 0.01). For benign and malignant tumors, the mean MK values (± SD) were 0.49 ± 0.17 and 1.14 ± 0.30, respectively, and ADCminvalues were 1.54 ± 0.47 and 0.49 ± 0.17 × 10−3mm2/s, respectively. At cutoffs of MK = 0.81 and ADCmin= 0.77 × 10−3mm2/s, the specificity and sensitivity for diagnosis of malignant tumors were 96.3 and 93.8% for MK and 96.3 and 93.8% for ADCmin, respectively. The areas under the curve were 0.97 and 0.99 for MK and ADCmin, respectively (p = 0.31). Conclusions: MK and ADCminshowed high diagnostic accuracy and strong correlation, reflecting the accuracy of MK. However, no clear added value of DKI could be demonstrated in differentiating musculoskeletal tumors.
  • 悪性化したgangliogliomaの1例, 小川 史子, 小川 正樹, 小澤 良之, 河合 辰哉, 北林 佑季也, 浦野 みすぎ, 芝本 雄太, Japanese Journal of Radiology, 36, (Suppl.) 18 - 18,   2018年02月
  • Assessment of the correlation between carotid artery plaque density determined by histogram analysis and positive remodeling on computerized tomography angiography, Masaki Ogawa, Yoshiyuki Ozawa, Masahiro Muto, Hiroyuki Katano, Kazuo Yamada, Toshiyasu Miura, Noriyuki Matsukawa, Yuta Shibamoto, Iranian Journal of Radiology, 15,   2018年01月01日, © 2018, Iranian Journal of Radiology. Background: CT angiography (CTA) was routinely performed for carotid artery disease, but the plaque characterization based on measurement of density may be inaccurate, influenced by adjacent calcification and contrast agent. Remodeling ratio was one of the additional new objective indexes for plaque characterization. On coronary CTA, the utility of histogram analysis was reported in a few studies. Objectives: The purpose of this study was to evaluate the diagnostic value of histogram analysis of carotid artery plaque density and positive remodeling on CTA for the diagnosis of pathologically proven complicated carotid artery plaques. Patients and Methods: We retrospectively evaluated 29 patients with atherosclerotic carotid artery stenosis treated by carotid endarterectomy. On CTA, the boundaries of non-calcified plaques were manually traced at the site of the greatest stenosis. In addition to the mean plaque density, the percentage of pixels (PP) with a density of less than 30 Hounsfield units (HU) (PP < 30) was calculated using the histogram analysis. We calculated the remodeling ratio by dividing the cross-sectional artery area at the greatest stenosis by normal reference-segment artery area. These results of CTA analysis were compared with the results of histological analysis based on the American heart association criteria. Results: Histologically, 13 of the 29 patients had complicated plaques. PP < 30 and the remodeling ratio were higher in patients with complicated plaques than in those with uncomplicated plaques (P = 0.023 and 0.002, respectively). Whereas, the mean plaque density did not differ between the two groups (P = 0.062). Correlation between PP < 30 and the remodeling ratio was stronger than the correlation between PP < 30 and the mean density (Spearman’s rs = 0.76 vs. 0.65, respectively). Conclusion: Histogram analysis of the carotid artery plaque density may be more useful for the evaluation of atherosclerosis on CTA compared with the conventional analysis of plaque densities, and the combined analysis of histogram analysis and the remodeling ratio may help to predict future stroke events.
  • A predictive diagnostic model using multiparametric MRI for differentiating uterine carcinosarcoma from carcinoma of the uterine corpus, Yuki Kamishima, Mitsuru Takeuchi, Tatsuya Kawai, Takatsune Kawaguchi, Ken Yamaguchi, Naoki Takahashi, Masato Ito, Toshinao Arakawa, Akiko Yamamoto, Kazushi Suzuki, Masaki Ogawa, Moe Takeuchi, Yuta Shibamoto, Japanese Journal of Radiology, 35,   2017年08月01日, © 2017, Japan Radiological Society. Purpose: To construct a diagnostic model for differentiating carcinosarcoma from carcinoma of the uterus. Materials and methods: Twenty-six patients with carcinosarcomas and 26 with uterine corpus carcinomas constituted a derivation cohort. The following nine MRI features of the tumors were evaluated: inhomogeneity, predominant signal intensity, presence of hyper- and hypointense areas, conspicuity of tumor margin, cervical canal extension on T2WI, presence of hyperintense areas on T1WI, contrast defect area volume percentage, and degree of enhancement. Two predictive models—with and without contrast—were constructed using multivariate logistic regression analysis. Fifteen other patients with carcinosarcomas and 30 patients with carcinomas constituted a validation cohort. The sensitivity and specificity of each model for the validation cohort were calculated. Results: Inhomogeneity, predominant signal intensity on T2WI, and presence of hyperintense areas on T1WI were significant predictors in the unenhanced-MRI-based model. Presence of hyperintensity on T1WI, contrast defect area volume percentage, and degree of enhancement were significant predictors in the enhanced-MRI-based model. The sensitivity/specificity of unenhanced MRI were 87/73 and 87/70% according to reviewer 1 and 2, respectively. The sensitivity/specificity of the enhanced-MRI-based model were 87/70% according to both reviewers. Conclusions: Our diagnostic models can differentiate carcinosarcoma from carcinoma of the uterus with high sensitivity and moderate specificity.
  • Usefulness of 3D balanced turbo-field-echo MR sequence evaluating the branching pattern of the intrahepatic bile ducts: comparison with drip infusion CT cholangiography, Masaki Ogawa, Yoshiyuki Ozawa, Kengo Ohta, Tomoya Sekiguchi, Shingo Omata, Misugi Urano, Yoichi Matsuo, Yuta Shibamoto, Abdominal Radiology, 42,   2017年07月01日, © 2017, Springer Science+Business Media New York. Purpose: For liver surgery, it is crucial to preoperatively examine the course of the right posterior bile duct. While MR cholangiopancreatography (MRCP) can only visualize the bile ducts, 3D balanced turbo-field-echo (BTFE) sequence clearly depicts the bile ducts and portal veins as well as drip infusion CT cholangiography (DIC-CT), without contrast media. We evaluated whether BTFE could substitute for DIC-CT. Materials and methods: Thirty patients undergoing MRCP and BTFE on 1.5-T MR and DIC-CT were evaluated. Two readers retrospectively evaluated the branching pattern (supra-type: A–C or infra-type: D–E) and scored the degree of confidence and motion artifacts using a 3-point scale for the three 2-mm-thick reconstructed images. Results: The bile duct diameter did not differ between DIC-CT and MRCP (p = 0.07). Five patients (17%) had intrahepatic biliary dilatation (>3 mm). The A, B, C, D, and E types were diagnosed in 21, 6, 1, 1, and 1 patient, respectively (28 supra-types and 2 infra-types) on DIC-CT. For DIC-CT, MRCP, and BTFE, the mean motion artifact scores were 3.0/3.0, 2.7/2.6, and 2.9/2.8, respectively. The mean diagnostic confidence scores were 2.9/2.9, 2.4/2.4, and 2.9/2.8, respectively, with no difference between DIC-CT and BTFE. The concordance between DIC-CT and BTFE was high (infra- or supra-type: κ = 1.00/1.00, A–E: κ = 0.86/0.66), but it was poor between DIC-CT and MRCP (infra- or supra-type: κ = 0.35/−0.05, A–E: κ = 0.33/0.41) for both readers. Conclusions: Similar to DIC-CT, the BTFE MR sequence had high diagnostic accuracy regarding the branching pattern of the intrahepatic bile duct, especially for the supra/infraportal type.
  • 多発血管炎性肉芽腫症(GPA)の経過中に気胸を発症したきわめて稀な1例, 松岡 哲平, 何澤 信礼, 後藤 多恵子, 小川 正樹, 板東 勇弥, 芝本 雄太, 難波 大夫, 飯田 真也, Japanese Journal of Radiology, 35, (Suppl.) 24 - 24,   2017年02月
  • Dual energy CTを用いたGGNの造影評価, 小澤 良之, 河合 辰哉, 中川 基生, 小川 正樹, 芝本 雄太, 鈴木 智博, 原 眞咲, Japanese Journal of Radiology, 35, (Suppl.) 24 - 24,   2017年02月
  • 胸腺カルチノイドの画像所見, 加藤 彩乃, 小澤 良之, 石原 由美, 真木 浩行, 小川 正樹, 関口 知也, 中川 基生, 櫻井 圭太, 芝本 雄太, 原 眞咲, Japanese Journal of Radiology, 35, (Suppl.) 34 - 34,   2017年02月
  • Volume of interest analysis of spatially normalized PRESTO imaging to differentiate between parkinson disease and atypical Parkinsonian syndrome, Keita Sakurai, Etsuko Imabayashi, Aya M. Tokumaru, Kimiteru Ito, Keigo Shimoji, Motoo Nakagawa, Yoshiyuki Ozawa, Masashi Shimohira, Masaki Ogawa, Satoru Morimoto, Ikuko Aiba, Noriyuki Matsukawa, Yuta Shibamoto, Magnetic Resonance in Medical Sciences, 16,   2017年01月01日, ©2016 Japanese Society for Magnetic Resonance in Medicine. Purpose: Various magnetic resonance imaging (MRI) techniques including T2*-weighted imaging, susceptibility- weighted imaging, and MR relaxometry had been performed to evaluate different patterns of brain iron depositions in Parkinsonian syndrome. The aim of the present study was to evaluate the diagnostic value of a volume of interest (VOI) analysis on the principles of echo shifting with a train of observations (PRESTO) imaging using the statistical parametric mapping (SPM) 8 and the WFU PickAtlas program for the diagnosis of Parkinsonian syndrome. Methods: Fifty subjects, including 13 with the Parkinsonian variant of multiple system atrophy (MSA-P), 12 with progressive supranuclear palsy (PSP), 12 with Parkinson’s disease (PD) and 13 controls were evaluated in this study. After the spatial normalization of PRESTO images on SPM8, the WFU PickAtlas program was performed to create target VOIs in the putamen, red nucleus, substantia nigra, subthalamic nucleus, and dentate nucleus. The signal intensity ratio (SIR) was calculated by normalizing the signal of each VOI to that of the cerebrospinal fluid space. These SIRs were used as determinants in receiver operating characteristic (ROC) analyses. Results: SIR of the putamen was significantly lower in MSA-P than in PSP (P = 0.0051) and controls (P = 0.0004). In contrast, SIR of the red nucleus was significantly lower in PSP than in MSA-P (P = 0.0003), PD (P = 0.0029), and controls (P = 0.0011). In ROC analyses, SIR of the putamen exhibited the highest areas under the curves (AUCs) of 0.83 (vs. PSP) and 0.91 (vs. controls) in the diagnosis of MSA-P. On the other hand, SIR of the red nucleus exhibited the highest AUCs of 0.87 (vs. MSA-P), 0.90 (vs. PD), and 0.89 (vs. controls) in the diagnosis of PSP. Conclusions: The VOI analysis based on spatially normalized PRESTO images may be useful for depicting hypointensity, indicative of abnormal iron depositions, of the putamen and red nucleus in the diagnosis of MSA-P and PSP.
  • Quality improvement of dual-energy lung perfusion image by reduction of low-energy X-ray spectrum: An evaluation on clinical images, Tatsuya Kawai, Yoshiyuki Ozawa, Masaki Ogawa, Kazuya Ohashi, Kazushi Suzuki, Yuta Shibamoto, Polish Journal of Radiology, 81,   2016年12月10日, © Pol J Radiol, 2016. Background: The effects of the reduction of low-energy X-ray spectrum on lung perfusion images created by dual-energy CT have not been well evaluated. The aim of this study is to investigate the reliability of lung perfusion blood volume (PBV) images created by dual-energy CT (DECT) equipped with or without a tin filter, focusing on its accuracy adjacent to high-attenuation areas. Material/Methods: Among 176 patients who underwent DECT for suspicion of pulmonary embolism, 38 patients (mean age, 64; range, 16 to 83 years) without apparent evidence of pulmonary embolism were evaluated in this study. They underwent DECT at 100/140 kVp with a tin filter on 140 kVp tube (Group A; n=18) or at 80/140 kVp without the filter (Group B; n=20). On the lung PBV images, the degrees of artifacts – pulmonary enhancement defect (PED) and pseudo-enhancement in the trachea (PTE) adjacent to the vena cava were evaluated using a four-point scale (0=minimal to 3=prominent). Results: The mean degrees of artifact in Group A were significantly lower than those in Group B (0.8 vs. 1.9; P<0.0001 for PED, respectively, and 1.1 vs. 2.2; P<0.0001 for TPE, respectively). The mean CTDIvols were 4.90±1.14 and 12.98±3.15 mGy (P<0.0001) for Group A and Group B, respectively. Conclusions: The quality and accuracy of dual-energy lung perfusion image will be improved by using the tin filter technique.
  • Utility of dual source CT with ECG-triggered high-pitch spiral acquisition (Flash Spiral Cardio mode) to evaluate morphological features of ventricles in children with complex congenital heart defects, Motoo Nakagawa, Yoshiyuki Ozawa, Norikazu Nomura, Sachiko Inukai, Satoshi Tsubokura, Keita Sakurai, Masashi Shimohira, Masaki Ogawa, Yuta Shibamoto, Japanese Journal of Radiology, 34,   2016年04月01日, © 2016, Japan Radiological Society. Purpose: We evaluated the ability of dual source CT (DSCT) with ECG-triggered high-pitch spiral acquisition (Flash Spiral Cardio mode) to depict the morphological features of ventricles in pediatric patients with congenital heart defects (CHD). Materials and methods: Between July 2013 and April 2015, 78 pediatric patients with CHD (median age 4 months) were examined using DSCT with the Flash Spiral Cardio mode. The types of ventricular abnormalities were ventricular septal defect (VSD) in 42 (the malaligned type in 11, perimembranous type in 23, supracristal type in 2, atrioventricular type in 2, and muscular type in 4), single ventricle (SV) in 11, and congenital corrected transposition of the great arteries (ccTGA) in 4. We evaluated the accuracy of the diagnosis of the VSD type. In cases of SV and ccTGA, we assessed the detectability of the anatomical features of both ventricles for a diagnosis of ventricular situs. Results: DSCT confirmed the diagnoses for all VSDs. The type of defect was precisely diagnosed for all patients. The anatomical features of both ventricles were also depicted and ventricular situs of SV and ccTGA was correctly diagnosed. Conclusion: The results suggest that DSCT has the ability to clearly depict the configuration of ventricles.
  • 子宮癌肉腫と子宮体癌の鑑別に有用なMRI所見の検討, 上嶋 佑樹, 竹内 充, 河合 辰哉, 川口 毅恒, 芝本 雄太, 竹内 萌, 鈴木 一史, 山本 晶子, 小川 正樹, 荒川 利直, 伊藤 雅人, Japanese Journal of Radiology, 34, (Suppl.) 28 - 28,   2016年02月
  • Shortened breath-hold contrast-enhanced MRI of the liver using a new parallel imaging technique, CAIPIRINHA (controlled aliasing in parallel imaging results in higher acceleration): a comparison with conventional GRAPPA technique, Masaki Ogawa, Tatsuya Kawai, Hirohito Kan, Susumu Kobayashi, Yoshihiro Akagawa, Kazushi Suzuki, Shunsuke Nojiri, Yoshiyuki Ozawa, Yuta Shibamoto, Abdominal Imaging, 40,   2015年06月23日, © 2015, Springer Science+Business Media New York. Purpose: We examined whether the shortened breath-hold 3-dimensional volumetric interpolated breath-hold examination (3D-VIBE) sequence for high acceleration factor (AF) using the controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA) could substitute for the conventional sequence using generalized autocalibrating partially parallel acquisition (GRAPPA) in patients undergoing routine gadoxetic acid-enhanced liver MRI. Materials and methods: Thirty patients with clinically suspected focal liver lesions were scanned using 3D-VIBE sequences with GRAPPA with AF = 2 and AF = 4 and CAIPIRINHA with AF = 4 (acquisition times: 21, 14, and 12 s, respectively) during the hepatobiliary phase. Visual evaluations using a 3- or 5-point scale and signal-to-noise ratio (SNR) analysis were performed for the 3 sequences. Results: For CAIPIRINHA with AF = 4, there was significantly less image noise in both visual evaluation and SNR analysis and fewer parallel imaging artifacts than for GRAPPA with AF = 4 (P < 0.0005); it was equal to GRAPPA with AF = 2 and had fewer motion artifacts than GRAPPA with AF = 2 and 4 (P < 0.0012). The liver edge sharpness and hepatic vessel clarity, lesion conspicuity, and overall image quality were rated significantly higher with CAIPIRINHA with AF = 4 than GRAPPA with AF = 2 and AF = 4 (P < 0.009). For GRAPPA with AF = 4, lesion conspicuity and overall image quality were rated significantly lower than for GRAPPA with AF = 2 (P < 0.012). Conclusion: The shortened breath-hold 3D-VIBE sequence using the new CAIPIRINHA technique with a high AF of 4 was superior to the conventional GRAPPA sequence. The shortened breath-hold sequence using GRAPPA with a high AF of 4 worsened the image quality and lesion conspicuity.
  • Internal carotid artery blister-like aneurysm caused by aspergillus - Case report, Masaki Ogawa, Keita Sakurai, Takatsune Kawaguchi, Aya Naiki-Ito, Motoo Nakagawa, Kenji Okita, Noriyuki Matsukawa, Yuta Shibamoto, Polish Journal of Radiology, 80,   2015年03月25日, © Pol J Radiol. Background: Blister-like aneurysm of the supraclinoid internal carotid artery (ICA) is a well-documented causeof subarachnoid hemorrhage. Generally, this type of aneurysm is associated with various conditions such as hypertension, arteriosclerosis, and ICA dissection. Although Aspergillus is the most common organism causing intracranial fungal aneurysmal formation, there is no report of a blisterlike aneurysm caused by Aspergillus infection. Case Report: An 83-year-old man received corticosteroid pulse therapy followed by oral steroid therapy for an inflammatory pseudotumor of the clivus. Two months later, the patient was transported to an emergency department due to the diffuse subarachnoid hemorrhage, classified as Fisher group 4. Subsequent 3D computed tomography angiogram revealed a blister-like aneurysm at the superior wall of the left ICA. Six days later, the patient died of subarachnoid hemorrhage caused by the left ICA aneurysm rerupture. Autopsy revealed proliferation of Aspergillus hyphae in the wall of the aneurysm. Notably, that change was present more densely in the inner membrane than in the outer one. Thus, it was considered that Aspergillus hyphae caused infectious aneurysm formation in the left ICA via hematogenous seeding rather than direct invasion. Conclusions: The blister-like aneurysm is a rare but important cause of subarachnoid hemorrhage. This case report documents another cause of blister-like aneurysms, that is an infectious aneurysm associated with Aspergillus infection.
  • 多系統萎縮症の脳血流SPECT画像統計解析の正診率, 櫻井 圭太, 真木 浩行, 小川 正樹, 武藤 昌裕, 小澤 良之, 芝本 雄太, 核医学, 51, (4) 425 - 425,   2014年11月
  • Total anomalous pulmonary venous connection in a 64-year-old man: A case report, Masaki Ogawa, Motoo Nakagawa, Masaki Hara, Masato Ito, Toshihiko Goto, Nobuyuki Ohte, Yuta Shibamoto, Annals of Thoracic and Cardiovascular Surgery, 19,   2013年02月28日, We report a 64-year-old man with incidentally found uncorrected total anomalous pulmonary venous connection (TAPVC). There have been only a few case reports of untreated TAPVC diagnosed after 60 years of age. Also, this is a first case report of TAPVC in which ECG-gated CT and phase-contrast cine magnetic resonance imaging (PC-MRI) was performed. He was referred to our hospital for the surgery of rectal cancer. He had been diagnosed to have an arterial septal defect (ASD) and persistent left superior vena cava (PLSVC), and Eisenmenger's syndrome was thought to be the cause of cyanosis at first. The vertical vein in TAPVC was initially misdiagnosed as PLSVC on enhanced axial CT images reconstructed with 5-mm slice thickness with gapless. ECG-gated CT and PC-MRI were useful to confirm the diagnosis. The vertical vein in TAPVC is morphologically similar to PLSVC. This kind of abnormality would be somewhat difficult to diagnose on non-ECGgated CT, and might be misdiagnosed as a large ASD and PLSVC. © 2012 The Editorial Committee of Annals of Thoracic and Cardiovascular Surgery. All rights reserved.
  • 多発性筋炎、皮膚筋炎の胸部CT所見, 荒川 利直, 小川 正樹, 松田 和哉, 河合 辰哉, 小林 晋, 南光 寿美礼, 芝本 雄太, 原 眞咲, Japanese Journal of Radiology, 31, (Suppl.I) 31 - 31,   2013年02月
  • 総肺静脈還流異常症の1成人例, 小川 正樹, 中川 基生, 河合 辰哉, 櫻井 圭太, 伊藤 雅人, 芝本 雄太, 原 眞咲, Japanese Journal of Radiology, 31, (Suppl.I) 32 - 32,   2013年02月
  • 肺癌取り扱い規約(第7版)を用いた病期診断におけるHigh-Definition PET Reconstruction(HD-PET)と従来法との比較, 小澤 良之, 伊藤 雅人, 河合 辰哉, 中川 基生, 小川 正樹, 太田 賢吾, 芝本 雄太, 原 眞咲, Japanese Journal of Radiology, 31, (Suppl.I) 39 - 39,   2013年02月
  • 前縦隔発生の平滑筋肉腫の1例, 太田 賢吾, 小澤 良之, 荒川 利直, 小川 正樹, 鈴木 一史, 黒坂 健一郎, 芝本 雄太, 原 眞咲, Japanese Journal of Radiology, 31, (Suppl.I) 39 - 39,   2013年02月
  • Cowden病の1例, 飯島 英紀, 竹内 充, 伊藤 雅人, 櫻井 圭太, 小川 正樹, 鈴木 梨津子, 芝本 雄太, 原 眞咲, Japanese Journal of Radiology, 31, (Suppl.I) 40 - 40,   2013年02月
  • Split-bolus CT-urography using dual-energy CT: Feasibility, image quality and dose reduction, Mitsuru Takeuchi, Tatsuya Kawai, Masato Ito, Masaki Ogawa, Kazuya Ohashi, Masaki Hara, Yuta Shibamoto, European Journal of Radiology, 81,   2012年11月01日, Purpose: To prospectively evaluate the feasibility of dual-energy (DE) split-bolus CT-urography (CTU) and the quality of virtual non-enhanced images (VNEI) and DE combined nephrographic-excretory phase images (CNEPI), and to estimate radiation dose reduction if true non-enhanced images (TNEI) could be omitted. Patients and methods: Between August and September 2011, 30 consecutive patients with confirmed or suspected urothelial cancer or with hematuria underwent DE CT. Single-energy TNEI and DE CNEPI were obtained. VNEI was reconstructed from CNEPI. Image quality of CNEPI and VNEI was evaluated using a 5-point scale. The attenuation of urine in the bladder on TNEI and VNEI was measured. The CT dose index volume (CTDI (vol)) of the two scans was recorded. Results: The mean image quality score of CNEPI and VNEI was 4.7 and 3.3, respectively. The mean differences in urine attenuation between VNEI and TNEI were 14 ± 15 [SD] and -16 ± 29 in the anterior and posterior parts of the bladder, respectively. The mean CTDI (vol) for TNEI and CNEPI was 11.8 and 10.9 mGy, respectively. Omission of TNEI could reduce the total radiation dose by 52%. Conclusion: DE split-bolus CTU is technically feasible and can reduce radiation exposure; however, an additional TNEI scan is necessary when the VNEI quality is poor or quantitative evaluation of urine attenuation is required. © 2012 2012 Elsevier Ireland Ltd. All rights reserved.
  • Dual-energy CT Can Evaluate Both Hilar and Mediastinal Lymph Nodes and Lesion Vascularity with a Single Scan at 60 Seconds after Contrast Medium Injection, Masaki Ogawa, Masaki Hara, Ayano Imafuji, Yoshiyuki Ozawa, Toshinao Arakawa, Susumu Kobayashi, Yuta Shibamoto, Academic Radiology, 19,   2012年08月01日, Rationale and Objectives: The aim of this study was to investigate whether 80-kVp and weighted-average 120-kVp computed tomographic (CT) images scanned at 60 seconds after contrast material injection using a dual-source CT scanner could substitute for conventional 120-kVp images obtained at 30 and 100 seconds. Materials and Methods: Eighty-three consecutive patients with suspected lung cancer were enrolled. Images were obtained in dual-energy mode (80 and 140 kVp) at 60 seconds and conventional 120-kVp mode at 30 and 100 seconds after contrast injection. The CT numbers of the pulmonary artery, pulmonary vein, hilar zone lymph nodes, and pulmonary lesions were measured. Contrasts between the pulmonary artery/pulmonary vein and lymph nodes and beam-hardening artifacts were visually evaluated using five-point and four-point scales, respectively. The degree of enhancement was evaluated on 30-second 120-kVp, 100-second 120-kVp, and 60-second weighted-average 120-kVp images. Results: The mean differences in attenuation between the pulmonary artery/pulmonary vein and lymph nodes on the 30-second 120-kVp, 60-second 80-kVp, and 60-second weighted-average 120-kVp images were 184/155, 130/140, and 84/92 Hounsfield units, respectively (all . P values <.001). The mean contrast scores for the hilar/mediastinal lymph nodes were 4.5/4.7, 3.7/4.2, 3.3/3.6, and 2.4/2.5 for these three and for 100-second 120-kVp images, respectively (all . P values <.01). The mean artifact scores of the four images were 1.2, 3.4, 3.6, and 4.0, respectively. On 60-second weighted-average 120-kVp images, 55 of 60 lesions (92%) showed higher enhancement than on 100-second conventional 120-kVp images. Conclusions: Dual-energy CT images scanned 60 seconds after contrast injection show excellent vessel-lymph node contrast and enhancement of lesions and can replace dual-phase scan protocols. © 2012 AUR.
  • アスペルギルス感染により内頸動脈瘤を形成し、くも膜下出血を来した1例, 川口 毅恒, 櫻井 圭太, 佐々木 繁, 小林 晋, 小川 正樹, 松田 和哉, 芝本 雄太, 原 眞咲, 内木 綾, 大喜多 賢治, Japanese Journal of Radiology, 30, (Suppl.I) 32 - 32,   2012年02月
  • 腎盂尿管移行部狭窄症に合併した巨大腎杯憩室の1例, 小川 正樹, 竹内 充, 佐藤 雅基, 伊藤 雅人, 芝本 雄太, 白木 法雄, 原 眞咲, Japanese Journal of Radiology, 30, (Suppl.I) 35 - 35,   2012年02月
  • Benign metastasizing leiomyoma of the lung with malignant transformation mimicking mediastinal tumor, Masaki Ogawa, Masaki Hara, Yoshiyuki Ozawa, Satoru Moriyama, Motoki Yano, Shigeki Shimizu, Yuta Shibamoto, Clinical Imaging, 35,   2011年09月01日, We report a rare case of benign metastasizing leiomyomas (BMLs) showing malignant transformation in one of them. A 65-year-old woman had a fever. Computed tomography (CT) revealed a mass on the left side of the anterior mediastinum and multiple nodules in bilateral lungs. The masses proved to be leiomyomas and a leiomyosarcoma. The latter showed heterogeneous contrast enhancement on CT and high heterogeneous uptake of18F-fluorodeoxyglucose (FDG) on positron emission tomography (PET)-CT. This case suggested the potential usefulness of PET-CT for differentiating these entities. © 2011 Elsevier Inc.
  • 胸壁皮下に発生した壊疽性膿皮症の1例, 荒川 利直, 原 眞咲, 小澤 良之, 小川 正樹, 芝本 雄太, 服部 日出雄, 日本医学放射線学会秋季臨床大会抄録集, 47回,   2011年09月
  • 【Multislice CT 2011 BOOK】 臨床 Dual energy CTの臨床応用と問題点, 竹内 充, 原 眞咲, 小川 正樹, 河合 辰哉, 中川 基生, 櫻井 圭太, 大橋 一也, 黒坂 健一郎, 今藤 綾乃, 鈴木 啓史, 芝本 雄太, 映像情報Medical, 43, (8) 92 - 99,   2011年07月
  • Dual energy CTにおける肺門・縦隔リンパ節描出能 造影開始60秒後撮影の検討, 小川 正樹, 原 眞咲, 今藤 綾乃, 鈴木 智博, 小澤 良之, 荒川 利直, 小林 晋, 芝本 雄太, 日本医学放射線学会学術集会抄録集, 70回,   2011年02月
  • 胸部及び手の単純X線写真読影実験 2MP vs. 3.9MsP LCD、1.3MP vs. 3.9MsP LCDの比較, 鈴木 智博, 小川 正樹, 河合 辰哉, 荒川 利直, 佐々木 繁, 芝本 雄太, 原 眞咲, 市川 勝弘, 日本医学放射線学会学術集会抄録集, 70回,   2011年02月
  • 多発性筋炎、皮膚筋炎の胸部CT所見, 荒川 利直, 原 眞咲, 小林 晋, 小川 正樹, 佐藤 雅基, 松田 和哉, 芝本 雄太, 日本医学放射線学会学術集会抄録集, 70回,   2011年02月
  • 前縦隔腫瘍との鑑別が問題となったbenign metastasizing leiomyoma(BML)およびその悪性転化の1例, 小川 正樹, 鈴木 智博, 南光 寿美礼, 小澤 良之, 伊藤 雅人, 芝本 雄太, 原 眞咲, 清水 重喜, Japanese Journal of Radiology, 29, (Suppl.I) 36 - 36,   2011年01月
  • 前縦隔腫瘍との鑑別が問題となった良性転移性平滑筋腫(BML)およびその悪性転化の1例, 小川 正樹, 河合 辰哉, 小澤 良之, 芝本 雄太, 原 眞咲, 清水 重喜, 日本医学放射線学会秋季臨床大会抄録集, 45回,   2009年09月


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