2022/11/29 更新

写真a

オカモト コウイチロウ
岡本 浩一郎
OKAMOTO Kouichirou
所属
脳研究所 生命科学リソース研究センター 特任教授
職名
特任教授
外部リンク

学位

  • 博士(医学) ( 1989年11月   新潟大学 )

研究キーワード

  • 神経放射線

  • コンピューター断層撮影

  • 血管造影

  • 脊髄

  • 磁気共鳴が像

  • 中枢神経

  • 放射線診断学

研究分野

  • ライフサイエンス / 放射線科学

経歴

  • 新潟大学   脳研究所 生命科学リソース研究センター   特任教授

    2021年4月 - 現在

  • 新潟大学   脳研究所 統合脳機能研究センター   准教授

    2016年4月 - 2021年3月

  • 新潟大学   脳研究所   准教授

    2005年10月 - 2016年3月

  • 新潟大学   医歯学総合研究科 生体機能調節医学専攻   准教授

    2005年10月 - 2016年3月

  • 新潟大学   医歯学総合研究科 医科学専攻   准教授

    2005年10月 - 2016年3月

  • 新潟大学   医学部   講師

    1995年7月 - 2001年4月

  • 新潟大学   歯学部   講師

    1990年7月 - 1995年6月

  • 新潟大学   歯学部   助手

    1989年7月 - 1990年6月

▶ 全件表示

所属学協会

委員歴

  • 日本医学放射線学会   代議員  

    2007年   

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    団体区分:学協会

    日本医学放射線学会
    ~2007

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  • 日本磁気共鳴学会   代議員  

    2005年   

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    団体区分:学協会

    日本磁気共鳴学会

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  • 日本神経放射線学会   評議員  

    2001年   

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    団体区分:学協会

    日本神経放射線学会

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取得資格

  • 医師

 

論文

  • Multiple aneurysms on the subarcuate artery arising from the anterior inferior cerebellar artery in a patient with a Borden type I transverse-sigmoid dural arteriovenous fistula manifesting as subarachnoid hemorrhage: A case report. 査読 国際誌

    Suzuki T, Okamoto K, Genkai N, Ito Y, Abe H

    Interventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences   25 ( 1 )   1591019918799299 - 96   2018年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1177/1591019918799299

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  • Aquaporin Positron Emission Tomography Differentiates Between Grade III and IV Human Astrocytoma. 査読 国際誌

    Yuji Suzuki, Yukihiro Nakamura, Kenichi Yamada, Satoshi Kurabe, Kouichirou Okamoto, Hiroshi Aoki, Hiroki Kitaura, Akiyoshi Kakita, Yukihiko Fujii, Vincent J Huber, Hironaka Igarashi, Ingrid L Kwee, Tsutomu Nakada

    Neurosurgery   82 ( 6 )   842 - 846   2018年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    BACKGROUND: Aquaporin (AQP) water channels play a significant role in mesenchymal microvascular proliferation and infiltrative growth. AQPs are highly expressed in malignant astrocytomas, and a positive correlation is observed between their expression levels and histological tumor grade. OBJECTIVE: To examine the utility of aquaporin positron emission tomography (PET) for differentiating between astrocytoma grade III and grade IV using the AQP radioligand [11C]TGN-020. METHODS: Fifteen astrocytoma patients, grade III (n = 7) and grade IV (n = 8), and 10 healthy volunteers underwent [11C]TGN-020 aquaporin PET imaging. Surgical tissues of astrocytoma patients were examined for histopathological grading using the WHO classification standard and expression of AQP1 and AQP4 immunohistochemically. RESULTS: Mean standardized uptake values of astrocytoma grade III and IV (0.51 ± 0.11 vs 1.50 ± 0.44, respectively) were higher than normal white matter (0.17 ± 0.02, P < .001) for both tumor grades. Importantly, mean standardized uptake values of astrocytoma grade IV were significantly higher than grade III (P < .01). CONCLUSION: Our study demonstrated that [11C]TGN-020 aquaporin PET imaging differentiated between astrocytoma grades III and IV. We suggest its clinical application as a noninvasive diagnostic tool would lead to advancements in the management of these malignant brain tumors.

    DOI: 10.1093/neuros/nyx314

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  • Reliable diagnosis of IDH-mutant glioblastoma by 2-hydroxyglutarate detection: a study by 3-T magnetic resonance spectroscopy. 査読 国際誌

    Manabu Natsumeda, Kunio Motohashi, Hironaka Igarashi, Takanori Nozawa, Hideaki Abe, Yoshihiro Tsukamoto, Ryosuke Ogura, Masayasu Okada, Tsutomu Kobayashi, Hiroshi Aoki, Hitoshi Takahashi, Akiyoshi Kakita, Kouichirou Okamoto, Tsutomu Nakada, Yukihiko Fujii

    Neurosurgical review   41 ( 2 )   641 - 647   2018年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    We have previously reported that reliable detection of 2-hydroxyglutarate (2HG) in isocitrate dehydrogenase (IDH)-mutant WHO grade 2 and 3 gliomas is possible utilizing 3.0-T single-voxel magnetic resonance spectroscopy (SVMRS). We set out to determine whether the same method could be applied to detect 2HG in IDH-mutant glioblastoma. Forty-four patients harboring glioblastoma underwent pre-operative MRS evaluation to detect 2HG and other metabolites. Presence of IDH-mutations was determined by IDH1 R132H immunohistochemical analysis and DNA sequencing of surgically obtained tissues. Six out of 44 (13.6%) glioblastomas were IDH-mutant. IDH-mutant glioblastoma exhibited significantly higher accumulation of 2HG (median 3.191 vs. 0.000 mM, p < 0.0001, Mann-Whitney test). A cutoff of 2HG = 0.897 mM achieved high sensitivity (100.0%) and specificity (92.59%) in determining IDH-mutation in glioblastoma. Glioblastoma with high 2HG accumulation did not have significantly longer overall survival than glioblastoma with low 2HG accumulation (p = 0.107, log-rank test). Non-invasive and reliable detection of 2HG in IDH-mutant glioblastoma was possible by 3.0-T SVMRS.

    DOI: 10.1007/s10143-017-0908-y

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  • Apparent diffusion coefficient reduction might be a predictor of poor outcome in patients with posterior reversible encephalopathy syndrome 査読

    Itaru Ninomiya, Masato Kanazawa, Yasuhisa Akaiwa, Takayoshi Shimohata, Kouichirou Okamoto, Osamu Onodera, Masatoyo Nishizawa

    JOURNAL OF THE NEUROLOGICAL SCIENCES   381   1 - 3   2017年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    It is thought that posterior reversible encephalopathy syndrome (PRES) is both clinically and radiologically reversible. However, its reversible nature has been challenged based on reports of permanent neurological impairments. The factors that predict the development of irreversible neurological impairment are still unclear. In the present study, we investigated clinical manifestations, laboratory findings, and neuroradiological images to identify predictors of functional outcomes in PRES. We investigated 23 PRES patients. Apparent diffusion coefficient (ADC) reduction was observed in 4 patients in the poor outcome group, whereas no patients presented ADC reduction in the favourable outcome group (p &lt; 0.01). Further studies are warranted to evaluate the association between ADC reduction and functional outcome after PRES. (C). 2017 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jns.2017.08.002

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  • An adult case of enterovirus D68 encephalomyelitis presenting as bilateral facial nerve palsy and dysphagia 査読

    Yuta Kusabe, Akari Takeshima, Azusa Seino, Mana Nishida, Mami Takahashi, Shota Yamada, Junsuke Shimbo, Aki Sato, Kouichirou Okamoto, Shuichi Lgarashi

    Brain and Nerve   69 ( 8 )   957 - 961   2017年8月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Igaku-Shoin Ltd  

    A 33-year-old man was admitted to our hospital with bilateral facial nerve paralysis, dysphagia, and muscle weakness in the neck and trunk following fever, headache and throat pain. T2-weighted brain magnetic resonance imaging (MRI) showed hyperintense lesions in the tegmentum of the brain stem and the ventral region of the superior cervical cord. Based on the characteristic findings on the brain MRI, we diagnosed the patient with enteroviral encephalomyelitis. Steroid therapy was administered
    however, his bilateral facial nerve paralysis and dysphagia were refractory to this therapy. Subsequently, enterovirus D68 was detected in the serum using polymerase chain reaction (PCR) analysis. At that time, an outbreak of enteroviral D68 infection was reported in Japan. Finally, we diagnosed encephalomyelitis caused by enteroviral D68 infection. Characteristic MRI findings were very useful in narrowing down the differential diagnosis in this patient.

    DOI: 10.11477/mf.1416200848

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  • [PRES: Posterior Reversible Encephalopathy Syndrome]. 査読

    Kouichirou Okamoto, Kunio Motohashi, Hidemoto Fujiwara, Tomohiko Ishihara, Itaru Ninomiya, Osamu Onodera, Yukihiko Fujii

    Brain and nerve = Shinkei kenkyu no shinpo   69 ( 2 )   129 - 141   2017年2月

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    記述言語:日本語  

    Posterior reversible encephalopathy syndrome (PRES) is suggested in patients with acute neurological symptoms in the appropriate clinical context, including acute hypertension, blood pressure fluctuations, renal failure, blood transfusion, immunosuppression, autoimmune disorders, and eclampsia. PRES is a clinical syndrome, and refers to a disorder with reversible subcortical vasogenic brain edema caused by endothelial dysfunction, predominantly involving the bilateral parieto-occipital regions. Although the clinical course and prognosis are favorable in most cases, intracranial hemorrhage and/or restricted diffusion similar to acute infarction could be seen in some lesions on brain magnetic resonance imaging (MRI). The spinal cord may be involved in some patients with posterior fossa lesions. Understanding the pathophysiology of PRES is helpful in making the correct early diagnosis and selecting appropriate therapies to improve its clinical course and outcome. Differentiation of PRES from strokes is critical in the setting of a neurological emergency.

    DOI: 10.11477/mf.1416200653

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  • Visualization of the Intimal Flap in Intracranial Arterial Dissection Using High-Resolution 3T MRI 査読

    Masahiro Uemura, Kenshi Terajima, Yuji Suzuki, Masaki Watanabe, Yasuhisa Akaiwa, Shinichi Katada, Kouichirou Okamoto, Masatoyo Nishizawa, Hironaka Igarashi, Tsutomu Nakada

    JOURNAL OF NEUROIMAGING   27 ( 1 )   29 - 32   2017年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    BACKGROUND AND PURPOSE: Presence of an intimal flap is a critical imaging finding in diagnosing intracranial artery dissection (ICAD). Recent reports showed that high-resolution magnetic resonance imaging (MRI) was better at identifying intimal flaps as compared with routine MRI techniques used in clinical settings. However, no current standardized sequence for high-resolution MRI without gadolinium enhancement produces images of satisfactory quality with clinically tolerable scanning times. This study evaluated a nonenhanced high-resolution fast spin echo (HR-FSE) MRI sequence for visualizing intimal flaps in patients with ICAD.
    SUBJECTS AND METHODS: Three patients with ICAD underwent plain MRI examination using a 2-dimensional T2-weighted FSE imaging sequence optimized for our 3T system (in-plane pixel size, .23 mm x .23 mm; slice thickness 3 mm with no interslice gap), as well as scanning with conventional modalities, including CT angiography, magnetic resonance angiography, and digital subtraction angiography. We assessed whether these imaging methods could visualize an intimal flap and/or double lumen sign in the participants and compared the results between HR-FSE and the other modalities.
    RESULTS: HR-FSE images clearly showed intimal flaps and double lumen signs in all 3 patients, whereas the conventional modalities identified a double lumen sign in only 2 of the 3 patients.
    CONCLUSIONS: The present method of optimized HR-FSE imaging with a 3T system improved visualization of intimal flaps and should thus be considered for assessing patients with suspected ICAD that cannot be definitively diagnosed by conventional imaging modalities.

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  • Clinicopathological features in anterior visual pathway in neuromyelitis optica 査読

    Mariko Hokari, Akiko Yokoseki, Musashi Arakawa, Etsuji Saji, Kaori Yanagawa, Fumihiro Yanagimura, Yasuko Toyoshima, Kouichirou Okamoto, Satoshi Ueki, Tetsuhisa Hatase, Riuko Ohashi, Takeo Fukuchi, Kohei Akazawa, Mitsunori Yamada, Akiyoshi Kakita, Hitoshi Takahashi, Masatoyo Nishizawa, Izumi Kawachi

    ANNALS OF NEUROLOGY   79 ( 4 )   605 - 624   2016年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    ObjectiveNeuromyelitis optica spectrum disorder (NMOsd) is an autoimmune disorder of the central nervous system characterized by aquaporin-4 (AQP4) autoantibodies. The aim of this study was to elucidate the characteristics of involvement of the anterior visual pathway (AVP) and neurodegeneration via glia-neuron interaction in NMOsd.
    MethodsThirty Japanese patients with serologically verified NMOsd were assessed with a neuro-ophthalmological study. Using 27 tissue blocks from 13 other cases of NMOsd, we performed neuropathological analysis of glial and neuroaxonal involvement in the AVP.
    ResultsThe AVP involvement in NMOsd was characterized by the following, compared to multiple sclerosis: (1) longitudinally extensive optic neuritis (ON); (2) more severe visual impairment and worse prognosis for ON; (3) unique AQP4 dynamics, including loss of AQP4 immunoreactivity on astrocytes with complement activation in ON lesions, loss of AQP4 immunoreactivity on Muller cells with no deposition of complement in the retinas, and densely packed AQP4 immunoreactivity on astrocytes in gliosis of secondary anterograde/retrograde degeneration in the optic nerves and retinal nerve fiber layer (RNFL); and (4) more severe neurodegeneration, including axonal accumulation of degenerative mitochondria and transient receptor potential melastatin 4 channel with complement-dependent astrocyte pathology in ON lesions, mild loss of horizontal cells, and RNFL thinning and loss of ganglion cells with abundance of AQP4(+) astrocytes, indicating secondary retrograde degeneration after ON.
    InterpretationSevere and widespread neuroaxonal damage and unique dynamics of astrocytes/Muller cells with alterations of AQP4 were prominent in the AVP and may be associated with poor visual function and prognosis in NMOsd. Ann Neurol 2016;79:605-624

    DOI: 10.1002/ana.24608

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  • Nonfunctional intra- and suprasellar tumor in a patient with visual disturbance and panhypopituitarism 査読

    Rie Saito, Shinya Jinguji, Yoshinori Taniguchi, Shigekazu Takeuchi, Kouichirou Okamoto, Masatoyo Nishizawa, Hitoshi Takahashi, Akiyoshi Kakita

    NEUROPATHOLOGY   36 ( 1 )   107 - 112   2016年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    DOI: 10.1111/neup.12236

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  • The Posterior Limb of the Internal Capsule as the Subcortical Transitional Zone of the Anterior and Posterior Circulations: Insights from Human 7T MRI 査読

    Satoshi Kurabe, Kouichirou Okamoto, Kiyotaka Suzuki, Hisothi Matsuzawa, Masaki Watanabe, Yuji Suzuki, Tsutomu Nakada, Yukihiko Fujii

    CEREBROVASCULAR DISEASES   41 ( 5-6 )   256 - 264   2016年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:KARGER  

    Background: In patients with cerebral infarction, identifying the distribution of infarction and the relevant artery is essential for ascertaining the underlying vascular pathophysiological mechanisms and preventing subsequent stroke. However, visualization of the basal perforating arteries (BPAs) has had limited success, and simultaneous viewing of background anatomical structures has only rarely been attempted in living human brains. Our study aimed at identifying the BPAs with 7T MRI and evaluating their distribution in the subcortical structures, thereby showing the clinical significance of the technique. Methods: Twenty healthy subjects and 1 patient with cerebral infarction involving the posterior limb of the internal capsule (ICpost) and thalamus underwent 3-dimensional fast spoiled gradient-echo sequence as time-of-flight magnetic resonance angiography (MRA) at 7T with a submillimeter resolution. The MRA was modified to detect inflow signals from BPAs, while preserving the background anatomical signals. BPA stems and branches in the subcortical structures and their origins were identified on images, using partial maximum intensity projection in 3 dimensions. Results: A branch of the left posterior cerebral artery (PCA) in the patient ran through both the infarcted thalamus and ICpost and was clearly the relevant artery. In 40 intact hemispheres in healthy subjects, 571 stems and 1,421 branches of BPAs were detected in the subcortical structures. No significant differences in the numbers of stems and branches were observed between the intact hemispheres. The numbers deviated even less across subjects. The distribution analysis showed that the subcortical structures of the telencephalon, such as the caudate nucleus, anterior limb of the internal capsule, and lenticular nucleus, were predominantly supplied by BPAs from the anterior circulation. In contrast, the thalamus, belonging to the diencephalon, was mostly fed by BPAs from the posterior circulation. However, compared with other subcortical structures, the ICpost, which marks the anatomical boundary between the telencephalon and the diencephalon, was supplied by BPAs with significantly more diverse origins. These BPAs originated from the internal carotid artery (23.1%), middle cerebral artery (38.5%), PCA (17.3%), and the posterior communicating artery (21.1%). Conclusions: The modified MRI method allowed the detection of the relevant BPA within the infarcted in the stroke survivor as well as the BPAs in the subcortical structures of living human brains. Based on in vivo BPA distribution analyses, the ICpost is the transitional zone of the anterior and posterior cerebral circulations. (C) 2016 S. Karger AG, Basel

    DOI: 10.1159/000443538

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  • Posterior Reversible Encephalopathy Syndrome in a Patient with Severe Uremia without Hypertension 査読

    Yoichi Iwafuchi, Kouichirou Okamoto, Yuko Oyama, Ichiei Narita

    INTERNAL MEDICINE   55 ( 1 )   63 - 68   2016年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:JAPAN SOC INTERNAL MEDICINE  

    A 28-year-old man was admitted to our hospital with nausea, headache and weakness of the left hand. He had severe uremia without hypertension due to recurrent/chronic pyelonephritis. Brain magnetic resonance imaging showed reversible vasogenic edema in the brainstem and bilateral frontal centrum semiovale. All of his neurological symptoms immediately improved after the introduction of hemodialysis. When a patient with uremia presents with neurological symptoms, posterior reversible encephalopathy syndrome should be considered in the differential diagnosis even if high blood pressure is not observed. Brain magnetic resonance imaging may be helpful in such a case, and an appropriate therapy could be subsequently initiated.

    DOI: 10.2169/internalmedicine.55.5563

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  • Varicella-zoster virus encephalitis localized to the bilateral medial temporal lobes 査読

    Ryuji Yajima, Kota Utsumi, Tomohiko Ishihara, Masato Kanazawa, Kouichirou Okamoto, Izumi Kawachi, Masatoyo Nishizawa

    Neurology: Neuroimmunology and NeuroInflammation   2 ( 4 )   e108   2015年

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    記述言語:英語   出版者・発行元:Lippincott Williams and Wilkins  

    DOI: 10.1212/NXI.0000000000000108

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  • Diffuse Brain Abnormalities in Myotonic Dystrophy Type 1 Detected by 3.0 T Proton Magnetic Resonance Spectroscopy 査読

    Yuhei Takado, Kenshi Terajima, Masaki Ohkubo, Kouichirou Okamoto, Takayoshi Shimohata, Masatoyo Nishizawa, Hironaka Igarashi, Tsutomu Nakada

    EUROPEAN NEUROLOGY   73 ( 3-4 )   247 - 256   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:KARGER  

    Patients with myotonic dystrophy type 1 (DM1) (n = 14) were compared with healthy controls (n = 13) using 3.0 T proton magnetic resonance spectroscopy (H-1-MRS) to investigate brain pathophysiology. H-1-MRS imaging revealed reduced N-acetylaspartate to creatine ratio (NAA/Cr) in multiple brain regions (average 24%), suggesting diffuse brain abnormalities among patients with DM1. Single-voxel H-1-MRS among patients with DM1 showed (1) reduced NAA in both the frontal cortex (23%) and frontal white matter (31%) and unaltered myo-inositol, suggesting neuronal abnormalities without significant gliosis; and (2) elevated glutamine in the frontal cortex (36%) and reduced glutamate in the frontal white matter (20%) among patients with DM1, suggesting abnormalities in the glutamatergic system in the brain of patients with DM1. We consider that these results reflect brain abnormalities that cannot be detected by neuropathological assessment in patients with DM1. (C) 2015 S. Karger AG, Basel

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  • Cerebral and spinal cord tanycytic ependymomas in a young adult with a mutation in the NF2 gene 査読

    Yoshihiro Kuga, Hideki Ohnishi, Yuji Kodama, Shuji Takakura, Masato Hayashi, Ryokichi Yagi, Kenji Fukutome, Ken Matsushima, Kouichirou Okamoto, Katsushi Taomoto, Hitoshi Takahashi

    NEUROPATHOLOGY   34 ( 4 )   406 - 413   2014年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    We studied one frontal lobe tumor and multiple spinal cord tumors (one in an extramedullary location) that had been resected from a 24-year-old man. The frontal lobe tumor was well demarcated and non-infiltrating, and consisted of eosinophilic, elongated fibrillary cells arranged in a fascicular pattern. A similar histology was reproduced in the spinal cord tumors, with additional areas showing standard features of ependymoma. Immunohistochemical and ultrastructural observations revealed that all the tumors were ependymal in nature with positivity for GFAP and epithelial membrane antigen and negativity for oligodendrocyte transcription factor 2, showing intra-and intercellular microrosettes, leading us to a diagnosis of tanycytic ependymoma for the frontal lobe tumor and tanycytic ependymoma with ordinary ependymomatous component for the spinal cord tumors. The spinal extramedullary tumor was a schwannoma. Importantly, a heterozygous truncating mutation in the NF2 gene was identified in the blood lymphocytes from the patient. It is known that multiple nervous system tumors can occur in neurofibromatosis type 2 (NF2), which is caused by mutation in the NF2 gene, and that occurrence of ependymoma, including the tanycytic variant, can be associated with this genetic condition. The present case provides further information about the clinicopathology of tanycytic ependymoma with details of the immunohistochemical, ultrastructural and genetic features.

    DOI: 10.1111/neup.12109

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  • Successful removal of a huge hypervascular tentorial cavernous angioma after preoperative endovascular embolization 査読

    Junichi Yoshimura, Yoshihiro Tsukamoto, Masakazu Sano, Hitoshi Hasegawa, Kazuhiko Nishino, Akihiko Saito, Masafumi Fukuda, Kouichirou Okamoto, Yukihiko Fujii

    JOURNAL OF NEUROSURGERY-PEDIATRICS   14 ( 1 )   43 - 47   2014年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER ASSOC NEUROLOGICAL SURGEONS  

    The authors report a rare case of a huge hypervascular tentorial cavernous angioma treated with preoperative endovascular embolization, followed by successful gross-total removal. A 15-year-old girl presented with scintillation, diplopia, and papilledema. Computed tomography and MRI studies revealed a huge irregularly shaped tumor located in the right occipital and suboccipital regions. The tumor, which had both intra- and extradural components, showed marked enhancement and invasion of the overlying occipital bone. Angiography revealed marked tumor stain, with blood supply mainly from a large branch of the left posterior meningeal artery. Therefore, this lesion was diagnosed as a tentorium-based extraaxial tumor. For differential diagnosis, meningioma, hemangiopericytoma, and malignant skull tumor were considered. Tumor feeders were endovascularly embolized with particles of polyvinyl alcohol. On the following day, the tumor was safely gross totally removed with minimum blood loss. Histopathological examination confirmed the diagnosis of cavernous angioma. To date, there have been no reports of tentorium-based cavernous angiomas endovascularly embolized preoperatively. A tentorial cavernous angioma is most likely to show massive intraoperative bleeding. Therefore, preoperative embolization appears to be quite useful for safe maximum resection. Hence, the authors assert that the differential diagnosis of tentorium-based tumors should include tentorial cavernous angioma, for which preoperative endovascular embolization should be considered.

    DOI: 10.3171/2014.4.PEDS13628

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  • Detectability of Neural Tracts and Nuclei in the Brainstem Utilizing 3DAC-PROPELLER 査読

    Taro Nishikawa, Kouichirou Okamoto, Hitoshi Matsuzawa, Makoto Terumitsu, Tsutomu Nakada, Yukihiko Fujii

    JOURNAL OF NEUROIMAGING   24 ( 3 )   238 - 244   2014年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    Despite clinical importance of identifying exact anatomical location of neural tracts and nuclei in the brainstem, no neuroimaging studies have validated the detectability of these structures. The aim of this study was to assess the detectability of the structures using three-dimensional anisotropy contrast-periodically rotated overlapping parallel lines with enhanced reconstruction (3DAC-PROPELLER) imaging. Forty healthy volunteers (21 males, 19 females; 19-53 years, average 23.4 years) participated in this study. 3DAC-PROPELLER axial images were obtained with a 3T-MR system at four levels of the brainstem: the lower midbrain, upper and lower pons, and medulla oblongata. Three experts independently judged whether five tracts (corticospinal tract, medial lemniscus, medial longitudinal fasciculus, central tegmental and spinothalamic tracts) and 10 nuclei (oculomotor and trochlear nuclei, spinal trigeminal, abducens, facial, vestibular, hypoglossal, prepositus, and solitary nuclei, locus ceruleus, superior and inferior olives) on each side could be identified. In total, 240 assessments were made. The five tracts and eight nuclei were identified in all the corresponding assessments, whereas the locus ceruleus and superior olive could not be identified in 3 (1.3%) and 16 (6.7%) assessments, respectively. 3DAC-PROPELLER seems extremely valuable imaging method for mapping out surgical strategies for brainstem lesions.

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  • Entrapment of the inferior horns of the lateral ventricle with enlargement of the bilateral choroid plexus 査読

    Ryosuke Ogura, Junichi Yoshimura, Masakazu Sano, Shouichi Kawasaki, Kenichi Nishiyama, Kouichirou Okamoto, Hitoshi Takahashi, Yukihiko Fujii, Akiyoshi Kakita

    NEUROPATHOLOGY   34 ( 2 )   210 - 213   2014年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

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  • Hypertrophic pachymeningitis: significance of myeloperoxidase anti-neutrophil cytoplasmic antibody 査読

    Akiko Yokoseki, Etsuji Saji, Musashi Arakawa, Takayuki Kosaka, Mariko Hokari, Yasuko Toyoshima, Kouichirou Okamoto, Shigeki Takeda, Kazuhiro Sanpei, Hirotoshi Kikuchi, Shunsei Hirohata, Kouhei Akazawa, Akiyoshi Kakita, Hitoshi Takahashi, Masatoyo Nishizawa, Izumi Kawachi

    BRAIN   137 ( Pt 2 )   520 - 536   2014年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

    The aim of this study was to elucidate the characteristics, pathogenesis and treatment strategy of hypertrophic pachymeningitis that is associated with myeloperoxidase anti-neutrophil cytoplasmic antibody (ANCA). We retrospectively investigated clinical, radiological, immunological and pathological profiles of 36 patients with immune-mediated or idiopathic hypertrophic pachymeningitis, including 17 patients with myeloperoxidase-ANCA, four patients with proteinase 3-ANCA, six patients with other immune-mediated disorders, and nine patients with 'idiopathic' variety. Myeloperoxidase-ANCA-positive hypertrophic pachymeningitis was characterized by: (i) an elderly female predominance; (ii) 82% of patients diagnosed with granulomatosis with polyangiitis (previously known as Wegener's granulomatosis) according to Watts' algorithm; (iii) a high frequency of patients with lesions limited to the dura mater and upper airways, developing headaches, chronic sinusitis, otitis media or mastoiditis; (iv) a low frequency of patients with the 'classical or generalized form' of granulomatosis with polyangiitis involving the entire upper and lower airways and kidney, or progressing to generalized disease, in contrast to proteinase 3-ANCA-positive hypertrophic pachymeningitis; (v) less severe neurological damage according to the modified Rankin Scale and low disease activity according to the Birmingham Vasculitis Activity Score compared with proteinase 3-ANCA-positive hypertrophic pachymeningitis; (vi) increased levels of CXCL10, CXCL8 and interleukin 6 in cerebrospinal fluids, and increased numbers of T cells, neutrophils, eosinophils, plasma cells and monocytes/macrophages in autopsied or biopsied dura mater with pachymeningitis, suggesting T(H)1-predominant granulomatous lesions in hypertrophic pachymeningitis, as previously reported in pulmonary or renal lesions of granulomatosis with polyangiitis; and (vii) greater efficacy of combination therapy with prednisolone and cyclophosphamide compared with monotherapy with prednisolone. Proteinase 3-ANCA may be considered a marker for more severe neurological damage, higher disease activity and a higher frequency of the generalized form compared with myeloperoxidase-ANCA-positive hypertrophic pachymeningitis. However, categorization into 'granulomatosis with polyangiitis' according to Watts' algorithm and immunological or pathological features were common in both proteinase 3- and myeloperoxidase-ANCA-positive hypertrophic pachymeningitis. These data indicate that most patients with myeloperoxidase-ANCA-positive hypertrophic pachymeningitis should be categorized as having the central nervous system-limited form of ANCA-associated vasculitis, consistent with the concept of ophthalmic-, pulmonary- or renal-limited vasculitis.

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  • Accumulation of 2-hydroxyglutarate in gliomas correlates with survival: a study by 3.0-tesla magnetic resonance spectroscopy 査読

    Manabu Natsumeda, Hironaka Igarashi, Toshiharu Nomura, Ryosuke Ogura, Yoshihiro Tsukamoto, Tsutomu Kobayashi, Hiroshi Aoki, Kouichirou Okamoto, Akiyoshi Kakita, Hitoshi Takahashi, Tsutomu Nakada, Yukihiko Fujii

    ACTA NEUROPATHOLOGICA COMMUNICATIONS   2   158   2014年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:BIOMED CENTRAL LTD  

    Introduction: Previous magnetic resonance spectroscopy (MRS) and mass spectroscopy studies have shown accumulation of 2-hydroxyglutarate (2HG) in mutant isocitrate dehydrogenase (IDH) gliomas. IDH mutation is known to be a powerful positive prognostic marker in malignant gliomas. Hence, 2HG accumulation in gliomas was assumed to be a positive prognostic factor in gliomas, but this has not yet been proven. Here, we analyzed 52 patients harboring World Health Organization (WHO) grade II and III gliomas utilizing 3.0-tesla MRS.
    Results: Mutant IDH gliomas showed significantly higher accumulation of 2HG (median 5.077 vs. 0.000, p = 0.0002, Mann-Whitney test). 2HG was detectable in all mutant IDH gliomas, whereas in 10 out of 27 (37.0%) wild-type IDH gliomas, 2HG was below the detectable range (2HG = 0) (p = 0.0003, chi-squared test). Screening for IDH mutation by 2HG analysis was highly sensitive (cutoff 2HG = 1.489 mM, sensitivity 100.0%, specificity 72.2%). Gliomas with high 2HG accumulation had better overall survival than gliomas with low 2HG accumulation (p = 0.0401, Kaplan-Meier analysis).
    Discussion: 2HG accumulation detected by 3.0-tesla MRS not only correlates well with IDH status, but also positively correlates with survival in WHO grade II and III gliomas.

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  • Pixel values of [15O]H2O PET images with OSEM algorithm depending on numbers of subset and iteration times: Comparative assessment to FBP 査読

    Rie Yamanoi, Kouichirou Okamoto, Kazunori Kawamura, Masaki Ohkubo, Yuji Suzuki, Yukihiro Nakamura

    Kakuigaku   51 ( 4 )   373 - 382   2014年

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Japanese Society of Nuclear Medicine  

    To investigate a potential application of ordered subsets expectation maximization (OSEM) algorithm for clinical [15O]H2O PET studies, region of interest (ROI) measurements were performed on both images with OSEM and fitered back projection (FBP). Forty OSEM images were reconstructed with variable combinations of numbers of the subset (1-40) and iteration times (2-12). PET scans were acquired using a PET/CT scanner (Discovery ST Elite, GE), and 3T-MRI images were obtained for fusion images. The mean values were measured on the frontal cortical regions in the middle cerebral artery distribution. Differences of the values between the OSEM and FBP were evaluated as %Error. Relationship between ROI mean values and the iteration times was investigated on the OSEM images. The smallest %Error 0.4% was measured in the combination of the subset number 10 and iteration times 8 [10, 8], and in that of [28, 2]. The mean values were stable with iteration number 8 or more. OSEM image with [28, 2] was reconstructed in a shorter time (2.5 min) than that with [10, 8] (6 min). OSEM image with [28, 2] was superior to that with [10, 8] in the qualitative evaluation. The mean values on OSEM images with [28, 2] were comparable with those on FBP images with little artifacts and higher spatial resolution. OSEM with optimal parameter setting seemed applicable for both quantitative and qualitative [15O]H2O PET studies.

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  • Oligodendroglioma (WHO grade I) in a young epilepsy patient: A specific entity lying within the spectrum of dysembryoplastic neuroepithelial tumor? 査読

    Hitoshi Takahashi, Akiyoshi Kakita, Masaru Tomikawa, Kouichirou Okamoto, Shigeki Kameyama

    NEUROPATHOLOGY   33 ( 6 )   645 - 651   2013年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    We studied a frontal lobe subcortical cystic tumor that had been resected from a 13-year-old girl with a 3-year history of intractable partial seizure. Currently, more than 13 years after surgery, the patient remains recurrence-free and has no neurological deficits. Histological examination showed that the tumor was non-infiltrating and paucicellular with a mucinous matrix, and consisted of fairly uniform small cells with round to oval nuclei. Within the mucinous matrix, the tumor cells were often arranged in pseudorosettes around small blood vessels. Mitotic activity and necrosis were absent, with a Ki-67 labeling index of &lt;1%. Based on the immunohistochemical and ultrastructural findings, the constituent tumor cells were considered to be those of oligodendroglioma, including mini-gemistocytes and gliofibrillary oligodendrocytes. No neuronal elements were identified. Features of cortical dysplasia (FCD Type 1) were evident in the cortex covering the lesion. The surrounding white matter also contained a significant number of ectopic neurons. The entire pathological picture appeared to differ somewhat from that of ordinary oligodendroglioma (WHO grade II). Considering the clinical and pathological features, the present unusual oligodendroglioma appeared to represent a previously undescribed form of oligodendroglioma (WHO grade I) lying within the spectrum of dysembryoplastic neuroepithelial tumor (DNT; WHO grade I). Simultaneously, the present oligodendroglioma also raises the question of whether or not oligodendrocyte-like cells of DNTs truly show neurocytic differentiation.

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  • Relapse of multiple sclerosis in a patient retaining CCR7-expressing T cells in CSF under fingolimod therapy 査読

    Akiko Yokoseki, Etsuji Saji, Musashi Arakawa, Mariko Hokari, Takanobu Ishiguro, Fumihiro Yanagimura, Tomohiko Ishihara, Kouichirou Okamoto, Masatoyo Nishizawa, Izumi Kawachi

    MULTIPLE SCLEROSIS JOURNAL   19 ( 9 )   1230 - 1233   2013年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SAGE PUBLICATIONS LTD  

    Fingolimod acts as a functional antagonist of the sphingosine-1-phosphate receptor, and it traps lymphocytes in secondary lymphoid organs and precludes their migration into the central nervous system. We report the case of a patient who suffered a relatively severe relapse of multiple sclerosis (MS) during the initial 3 months of fingolimod therapy, with retention of CCR7 expression on CD4(+) T cells in the cerebrospinal fluid (CSF) despite decreased numbers of lymphocytes and decreased expression of CCR7 on CD4(+) T cells in the blood. These data suggest that fingolimod may cause differential effects on the CSF and blood lymphocytes of patients with MS during the initial months of therapy.

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  • Epstein-Barr virus-associated primary central nervous system cytotoxic T-cell lymphoma 査読

    Ryosuke Ogura, Hiroshi Aoki, Manabu Natsumeda, Hiroshi Shimizu, Tsutomu Kobayashi, Tomohisa Saito, Jun Takizawa, Kouichirou Okamoto, Go Hasegawa, Hajime Umezu, Kouichi Ohshima, Hitoshi Takahashi, Yukihiko Fujii, Akiyoshi Kakita

    NEUROPATHOLOGY   33 ( 4 )   436 - 441   2013年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    Primary central nervous system lymphoma (PCNSL) expressing T-cell markers is rare, among which nasal-type extranodal NK/T-cell lymphoma is an extremely rare subtype associated with Epstein-Barr virus (EBV) infection. Here we report the clinicopathologic features of a case of EBV-associated PCNSL showing a cytotoxic T-cell phenotype. The patient, a 73-year-old woman, presented with rapidly progressive mental deterioration. Brain MRI revealed multiple lesions with swelling in the bilateral cerebral hemispheres, which were hypointense on T1-weighted images, hyperintense on T2-weighted and fluid-attenuated inversion recovery images, and slightly hyperintense on diffusion-weighted images. Biopsy specimens from the temporal region showed many medium-sized anaplastic lymphocytic cells with perivascular and angio-invasive patterns in the cortex. Immunohistochemically, the cells were positive for CD3, CD8, T-cell-restricted intracellular antigen-1 (TIA-1), granzyme B and perforin, but negative for CD56 and CD20. In situ hybridization revealed EBV-encoded RNAs in the tumor cell nuclei. A rearrangement study showed T-cell receptor g-chain gene rearrangement with a clonal appearance. The patient died 6 months after surgery, and a general autopsy revealed no lymphoma cells outside the brain. These cellular profiles are inconsistent with those of extranodal NK/T-cell lymphoma, and have not been previously described. This case appears to represent an unusual CNS manifestation of EBV-associated T-cell lymphoma.

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  • Progressive multifocal leukoencephalopathy developed 26 years after renal transplantation 査読

    Shigemi Nagayama, Yuichiro Gondo, Shin-ichi Araya, Naomi Minato, Michiyo Fujita-Nakata, Muichi Kaito, Megumi Nakanishi, Keiko Tanaka, Hideki Yamaya, Hitoshi Yokoyama, Kazuo Nakamichi, Masayuki Saijo, Kouichirou Okamoto, Yasuko Toyoshima, Akiyoshi Kakita, Makoto Matsui

    CLINICAL NEUROLOGY AND NEUROSURGERY   115 ( 8 )   1482 - 1484   2013年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

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  • High frequency of calcification in basal ganglia on brain computed tomography images in Japanese older adults 査読

    Megumi Yamada, Takahiko Asano, Kouichirou Okamoto, Yuichi Hayashi, Masayuki Kanematsu, Hiroaki Hoshi, Yasuhisa Akaiwa, Takayoshi Shimohata, Masatoyo Nishizawa, Takashi Inuzuka, Isao Hozumi

    GERIATRICS & GERONTOLOGY INTERNATIONAL   13 ( 3 )   706 - 710   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    Aim: To investigate the frequency of calcification in the basal ganglia and the dentate nuclei in the cerebellum, and compare the difference in age and area, we examined the brain computed tomography (CT) images of all patients in two representative university hospitals in Japan.
    Methods: We examined the brain CT images of 2526 patients in Gifu University Hospital (UH) and 2573 patients in Niigata UH. These patients were examined in these hospitals from October 2009 to September 2010.
    Results: Punctate calcification of the basal ganglia was observed in 435 of 2526 patients (17.2%) in Gifu UH and 530 of 2573 patients (20.6%) in Niigata UH. The frequency of calcification increased with age. Patchy calcification of the basal ganglia was observed in 32 (1.3%) and 50 patients (1.9%) in Gifu UH and Niigata UH, respectively. Among patients aged over 65 years, 24 (2.1%) and 34 (3.1%) patients showed patchy calcification in Gifu UH and Niigata UH, respectively. Calcification of the cerebellar dentate nuclei was detected in just seven and four patients in Gifu UH and Niigata UH, respectively.
    Conclusion: Compared with previous reports, the frequency of calcification of the basal ganglia in this study markedly increased. This might be because of the increased number of older adults and the increased sensitivity of CT. Geriatr Gerontol Int 2013; 13: 706-710.

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  • Radiation-induced intracranial osteosarcoma after radiation for acute lymphocytic leukemia associated with Li-Fraumeni syndrome 査読

    Junichi Yoshimura, Manabu Natsumeda, Yasushi Nishihira, Kenichi Nishiyama, Akihiko Saito, Kouichirou Okamoto, Hitoshi Takahashi, Yukihiko Fujii

    Neurological Surgery   41 ( 6 )   499 - 505   2013年6月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)  

    A 28-year-old man presented with osteosarcoma of the occipital bone 16 years after 24 Gy of craniospinal irradiation for acute lymphocytic leukemia. The tumor had both intra- and extracranial components. However, the affected skull appeared to be normal on imaging because of permeative infiltration by the tumor. Subtotal resection was achieved and the tumor was verified histologically as an osteosarcoma. The residual tumor soon showed remarkable enlargement and disseminated to the spinal cord. Both of the enlarged and disseminated tumor masses were treated by surgical intervention and chemotherapy. However, the patient deteriorated due to the tumor regrowth and died 11 months after the initial diagnosis. This patient had previously developed a leukemia, a colon cancer, a rectal cancer and a hepatocellular carcinoma. His brother also died of leukemia. The patient had a heterozygous TP53 germ-line mutation of codon 248 in the exon 7. In conclusion, we consider the present tumor to be a rare example of radiation-induced skull osteosarcoma in a member of the cancer-prone family with TP53 germline mutation which is associated with Li-Fraumeni syndrome.

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  • Cerebral astroblastoma in an adult: An immunohistochemical, ultrastructural and genetic study 査読

    Yong-Juan Fu, Yoshinori Taniguchi, Shigekazu Takeuchi, Atsushi Shiga, Kouichirou Okamoto, Junko Hirato, Sumihito Nobusawa, Yoichi Nakazato, Akiyoshi Kakita, Hitoshi Takahashi

    Neuropathology   33 ( 3 )   312 - 319   2013年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Astroblastoma is a rare glial tumor of unknown origin, usually affecting the cerebral hemispheres of children and young adults. Here we report an unusual cerebral tumor in a 60-year-old woman. On MRI, the tumor appeared as a well circumscribed lesion in the left frontal lobe. Histopathologically, it was composed of rounded eosinophilic cells, and was divisible into two areas. One area was characterized by a collection of GFAP-positive cells around sclerotic blood vessels (astroblastic pseudorosettes and perivascular hyalinization), and had a Ki-67 labeling index of 2.8%. However, the other area was highly cellular, showing many GFAP-negative cells often with a rhabdoid appearance, mitoses and a Ki-67 index of 15.7%. Thus, a final diagnosis of malignant astroblastoma was made. In both areas of the tumor, nearly all the cells were positive for epithelial membrane antigen, and many were positive for oligodendrocyte transcription factor 2 (Olig2). Focal expression of cytokeratin was also evident. With regard to genetic markers, the tumor cells were positive for INI1 and negative for mutant IDH1. The p53 labeling index was &lt
    1%. Ultrastructurally, the presence of intra- and intercellular lumina with microvilli was a feature. DNA examination of IDH1/2 and TP53 showed no mutations. In conclusion, although ependymal features were evident ultrastructurally in the present tumor, the immunohistochemical expression pattern of Olig2 was that of diffuse astrocytoma. On the other hand, the absence of mutations in both IDH1/2 and TP53 suggested that the present tumor was not a purely astrocytic neoplasm. Further studies, including molecular and genetic analyses, will provide insight into the histogenesis of astroblastoma. © 2012 Japanese Society of Neuropathology.

    DOI: 10.1111/j.1440-1789.2012.01351.x

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  • Amyloid beta-related angiitis: Brain lesions showing leptomeningeal gadolinium enhancement on MRI and characteristic surgical pathologic features 査読

    Yuka Koike, Haruka Ouchi, Tomoe Sato, Junsuke Shimbo, Aki Sato, Osamu Sasaki, Hiroyuki Shibuya, Kouichirou Okamoto, Akiyoshi Kakita, Shuichi Igarashi

    Brain and Nerve   65 ( 6 )   693 - 697   2013年6月

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)  

    Amyloid-β-related angiitis (ABRA) of the CNS occurs in association with vasculitis of small-and medium-sized leptomeningeal arteries. Here, we describe the clinicopathological features of a 76-year-old man with ABRA. The patient suffered progressive truncal oscillation, aphasia, and recent memory disturbance with a subacute disease onset. His cerebrospinal fluid showed a mild increase in protein levels (101 mg/dL) and pleocytosis (8/mm3). High-intensity brain lesion were detected on T2-weighted and FLAIR MRI scans, and prominent spread of gadolinium enhancement spreading was observed through the sulci of the left occipital and temporal lobes and left cerebellar hemisphere. A biopsy of the left temporal lesion showed a granulomatous and angiodestructive inflammation with infiltration of many CD4+ T-lymphocytes and multinucleated giant cells and with fibrinoid necrosis of the arterial walls in the subarachnoid space. Immunolabeling for Aβ1-40 revealed the abundant deposition of this protein in the affected arteries. On the basic of the diagnosis of ABRA, immunosuppressive therapy was conducted, and it ameliorated the clinical course.

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  • Decreased vestibular signal intensity on 3D-FIESTA in vestibular schwannomas differentiating from meningiomas 査読

    Kazuhiro Ishikawa, Jun Haneda, Kouichirou Okamoto

    NEURORADIOLOGY   55 ( 3 )   261 - 270   2013年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER  

    With reported characteristic MR features, it is difficult to differentiate vestibular schwannomas (VSs) from cerebellopontine angle (CPA) meningiomas (CPAMs) in some cases. This study aimed to evaluate vestibular signal intensity changes in patients with VS and those with CPAM on three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA), and to test the effectiveness of the signal intensity change to differentiate these two common CPA tumors.
    We retrospectively reviewed 21 patients with unilateral VS, six patients with unilateral CPAM, and 25 control subjects. Setting regions of interest in the bilateral vestibules and cerebellar white matter on 3D-FIESTA, we compared the ratio of the signal intensity (SIR) of the vestibule to that of the cerebellar white matter (SIRv) among the VS, CPAM, and control subject groups. We also compared the ratio of SIRv on the affected side (a-SIRv) to that on the unaffected side (AURv) between the VS and CPAM.
    The a-SIRv in the VS group was significantly lower than the overall SIRv in the control subjects (pre-contrast, P &lt; 0.001; post-contrast, P &lt; 0.001) and the a-SIRv in the CPAM group (pre-contrast, P = 0.001; post-contrast, P = 0.001). The AURv in the VS group was significantly lower than that in the CPAM groups (pre-contrast, P &lt; 0.001; post-contrast, P &lt; 0.001).
    Decreased vestibular signal intensity on the affected side on 3D-FIESTA was observed in patients with VS, but not in those with CPAM or in normal subjects. The signal intensity change has the potential to be used in differentiating VS from CPAM.

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  • Occurrence of metachronous pure germinomas long after treatment of a mixed germ cell tumor containing yolk sac tumor and germinoma Case report 査読

    Shinya Jinguji, Kouichirou Okamoto, Junichi Yoshimura, Yuichiro Yoneoka, Ryousuke Ogura, Akihiko Saito, Yukihiko Fujii

    JOURNAL OF NEUROSURGERY-PEDIATRICS   11 ( 1 )   68 - 73   2013年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER ASSOC NEUROLOGICAL SURGEONS  

    The authors report a rare case involving the occurrence of metachronous pure germinomas long after treatment of a mixed germ cell tumor (GCT) categorized as having a poor prognosis. A neurohypophysial germinoma occurred 4 years and 6 months after the initial treatment of a mixed pineal GCT containing a yolk sac tumor and a germinoma. Furthermore, intramedullary germinomas occurred 21 years after the initial treatment of the mixed GCT and 15 years after the second treatment of the neurohypophysial germinoma. The neurohypophysial germinoma was not confirmed histopathologically, but the intramedullary germinoma was histopathologically diagnosed as a pure germinoma. Serum alpha-fetoprotein levels at the second neurohypophysial and third intramedullary occurrences of the germinomas were less than 10 ng/ml. Therefore, no yolk sac components seemed to be contained in the tumors. The second neurohypophysial and third intramedullary germinomas might be recurrences of the germinoma component of the pineal mixed GCT, which consisted of a yolk sac tumor and a germinoma. However, it seems very unlikely that only the germinoma, categorized in the good prognosis group, would be the only one to recur. Hence, it seems plausible that both the second and the third occurrences of pure germinoma were de novo metachronous GCTs arising after the pineal mixed GCT was cured. The authors' case indicates the possibility of multicentric GCTs in the CNS. (http://thejns.org/doi/abs/10.3171/2012.9.PEDS12151)

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  • Cognitive Impairment and Cortical Degeneration in Neuromyelitis Optica 査読

    Etsuji Saji, Musashi Arakawa, Kaori Yanagawa, Yasuko Toyoshima, Akiko Yokoseki, Kouichirou Okamoto, Mika Otsuki, Kohei Akazawa, Akiyoshi Kakita, Hitoshi Takahashi, Masatoyo Nishizawa, Izumi Kawachi

    ANNALS OF NEUROLOGY   73 ( 1 )   65 - 76   2013年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    Objective: Neuromyelitis optica spectrum disorder (NMOsd) is an inflammatory and demyelinating syndrome characterized by optic neuritis and myelitis. Several magnetization transfer magnetic resonance imaging (MRI) studies have revealed abnormalities in normal-appearing gray matter in NMOsd. The aim of this study is to elucidate the characteristics and pathogenesis of cognitive impairment and neurodegeneration in NMOsd brains.
    Methods: Fourteen Japanese patients with serologically verified NMOsd, 17 patients with multiple sclerosis (MS), and 37 healthy controls were assessed with the Rao's Brief Repeatable Battery of Neuropsychological Tests (BRBN). Using 128 tissue blocks from 6 other cases of NMOsd, 3 cases of MS, and 4 controls without central nervous system involvement, we performed quantitative analysis of cortical neuronal loss and layer-specific changes in NMOsd.
    Results: In BRBN assessments, 57% of NMOsd patients and 47% of MS patients had impaired performance on at least 3 cognitive tests. Cognitive impairment in NMOsd was common even in the limited form of disease, indicating that NMOsd may progress insidiously from early stages of disease. Neuropathological assessments showed neuronal loss in cortical layers II, III, and IV, with nonlytic reaction of aquaporin-4 (AQP4)-negative astrocytes in layer I, massive activated microglia in layer II, and meningeal inflammation in NMOsd brains. All NMO cases showed no evidence of cortical demyelination.
    Interpretation: We demonstrate cognitive impairment and substantial cortical neuronal loss with unique AQP4 dynamics in astrocytes in NMOsd. These data indicate pathological processes consisting not only of inflammatory demyelinating events characterized by pattern-specific loss of AQP4 immunoreactivity but also cortical neurodegeneration in NMOsd brains. ANN NEUROL 2013;73:65-76

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  • Supratentrial extradural endodermal cyst involving the frontal bone 査読

    Satoshi Kurabe, Kouichirou Okamoto, Osamu Sasaki, Yukihiko Fujii

    ACTA NEUROCHIRURGICA   153 ( 12 )   2493 - 2494   2011年12月

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    記述言語:英語   出版者・発行元:SPRINGER WIEN  

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  • Brainstem Metabolites in Multiple System Atrophy of Cerebellar Type: 3.0-T Magnetic Resonance Spectroscopy Study 査読

    Yuhei Takado, Hironaka Igarashi, Kenshi Terajima, Takayoshi Shimohata, Tetsutaro Ozawa, Kouichirou Okamoto, Masatoyo Nishizawa, Tsutomu Nakada

    MOVEMENT DISORDERS   26 ( 7 )   1297 - 1302   2011年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    Background: The aim of this study was to find biomarkers of disease severity in multiple system atrophy of cerebellar type by imaging disease specific regions using proton magnetic resonance spectroscopy on a 3.0 T system.
    Methods: We performed proton magnetic resonance spectroscopy separately in the pons and medulla on 12 multiple system atrophy of cerebellar type patients and 12 age and gender matched control subjects. The metabolite concentrations were estimated from single-voxel proton magnetic resonance spectra measured by point resolved spectroscopy, which were then correlated with clinical severity using Part I, II, and IV of the unified multiple system atrophy rating scale.
    Results: Proton magnetic resonance spectroscopy showed that myo-inositol concentrations in both the pons and medulla were significantly higher in multiple system atrophy of cerebellar type patients compared to those of the control subjects (P &lt; 0.05). By contrast, total N-acetylaspartate (the sum of N-acetylaspartate and N-acetylaspartylglutamate) and total choline compounds concentrations in both the pons and medulla were significantly lower in multiple system atrophy of cerebellar type patients compared to control subjects (P &lt; 0.05). Creatine concentration in the pons was significantly higher in multiple system atrophy of cerebellar type patients compared to the control subjects (P &lt; 0.05). Furthermore, a significant correlation was found between the myo-inositol/creatine ratio in the pons and clinical severity, defined by the sum score of unified multiple system atrophy rating scale (I+II+IV) (r = 0.76, P &lt; 0.01).
    Conclusion: Proton magnetic resonance spectroscopy, in conjunction with a 3.0 T system, can be feasible to detect part of pathological changes in the brainstem, such as gliosis and neuronal cell loss, and the metabolites can be used as biomarkers of clinical severity in multiple system atrophy of cerebellar type patients. (C) 2011 Movement Disorder Society

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  • Intraventricular pleomorphic xanthoastrocytoma with anaplastic features 査読

    Yong-Juan Fu, Hiroaki Miyahara, Takeo Uzuka, Manabu Natsumeda, Kouichirou Okamoto, Takanori Hirose, Yukihiko Fujii, Hitoshi Takahashi

    NEUROPATHOLOGY   30 ( 4 )   443 - 448   2010年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    Pleomorphic xanthoastrocytoma (PXA) is a rare astrocytic tumor that usually occurs in the superficial cerebral hemispheres of children and young adults and has a relatively favorable prognosis. We report an unusual case of supratentorial, intraventricular tumor in a 52-year-old man. The tumor was composed of pleomorphic cells, including giant cells, most of which were multinucleated, and small cells. In addition, frequent xanthic changes in the cytoplasm of the tumor cells, and widespread reticulin deposits and lymphocytic infiltrates in the stroma were characteristic features. Large areas of necrosis were also evident. However, mitotic figures were rare (1-2 mitoses per 10 high-power fields). Many tumor cells were positive for GFAP, and a number were positive for neurofilament protein and synaptophysin, indicating their neuronal differentiation. In addition, occasional tumor cells were positive for CD34. p53 protein was entirely negative in the tumor cells. In diagnosing this tumor histopathologically, differentiation between PXA and giant cell glioblastoma (GCG), a rare variant of glioblastoma, was problematic. However, considering the overall histopathological picture, a final diagnosis of PXA with anaplastic features was made. The present case indicates that PXA can occur as an intraventricular tumor, and suggests that in some instances, it would be very difficult to differentiate PXA and GCG histopathologically.

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  • Alzheimer&apos;s disease: Report of two autopsy cases with a clinical diagnosis of corticobasal degeneration 査読

    Kenichi Okazaki, Yong-Juan Fu, Yasushi Nishihira, Minoru Endo, Takao Fukushima, Takeshi Ikeuchi, Kouichirou Okamoto, Osamu Onodera, Masatoyo Nishizawa, Hitoshi Takahashi

    NEUROPATHOLOGY   30 ( 2 )   140 - 148   2010年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL PUBLISHING, INC  

    Alzheimer&apos;s disease (AD) is the most common cause of dementia in the elderly. Corticobasal degeneration (CBD) is a rare neurodegenerative disease affecting adults, being characterized clinically by a combination of extrapyramidal signs and focal cortical syndromes. In both diseases, tau deposits are a characteristic neuropathological feature. We report two new patients with autopsy-proven AD, in whom clinical diagnoses of CBD were made during life. The ages of the patients at onset were 52 and 67 years, and the disease durations were 9 and 15 years, respectively. At autopsy, both cases exhibited marked cortical atrophy with evident neuronal loss in the convex areas of the frontal and parietal lobes. Immunohistochemically, AT8-positive neurofibrillary tangles (NFTs) and A beta-positive senile plaques (SPs) were widespread and abundant in the cerebral cortex (Alzheimer pathology stage VI/C of Braak and Braak), leading us to the final pathological diagnosis of AD. No tau lesions suggestive of CBD were observed, and the deep gray matter areas, including the substantia nigra, were unremarkable (exceptionally, only mild neuronal loss was noted in the putamen in case 2). These findings further strengthen the idea that in AD, neurodegeneration with tau and A beta deposits may begin in the fronto-parietal neocortical areas, which are often preferentially affected in CBD, earlier than, or as early as the medial temporal lobe, and that extrapyramidal signs, such as rigidity and tremor, can occur in the absence of neuronal loss in the basal ganglia and substantia nigra.

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  • Focal T2 hyperintensity in the dorsal brainstem in patients with vestibular schwannoma.

    AJNR Am J Neuroradiol   (in print)   2006年

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  • [Imaging of the brain tumor: overview]. 査読

    Okamoto K, Ishikawa K, Furusawa T

    Nihon rinsho. Japanese journal of clinical medicine   63 Suppl 9   207 - 211   2005年9月

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  • Quantitative evaluation of brainstem involvement in multiple system atrophy by diffusion-weighted MR imaging 査読

    M Kanazawa, T Shimohata, K Terajima, O Onodera, K Tanaka, S Tsuji, K Okamoto, M Nishizawa

    JOURNAL OF NEUROLOGY   251 ( 9 )   1121 - 1124   2004年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:DR DIETRICH STEINKOPFF VERLAG  

    In multiple system atrophy (MSA), symptoms associated with dysfunctions of the brainstem and autonomic nervous system are important prognostic factors. We investigated brainstem involvement in 12 patients with MSA with predominant cerebellar symptoms (MSA-C) (mean age, 56.3 +/- 9.9 years, median disease duration, 3 years), and 11 controls (57.6 +/- 12.0 years) matched for age using diffusion-weighted MR imaging (DWI). We demonstrated that apparent diffusion coefficients (ADCs) in the pons and middle cerebellar peduncle of MSA-C patients are significantly higher than those of normal controls even though the patients are in the early stage of the disease. Furthermore, we demonstrated that increased ADC values correlated well with the disease duration. The current study demonstrated that DWI is a useful noninvasive method for the quantitative evaluation of the brainstem involvement in MSA-C patients.

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  • Clinical and imaging features of distended scapulothoracic bursitis - Spontaneously regressed pseudotumoral lesion 査読

    T Higuchi, A Ogose, T Hotta, K Okamoto, T Kamura, K Sasai, H Hatano, T Morita

    JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY   28 ( 2 )   223 - 228   2004年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:LIPPINCOTT WILLIAMS & WILKINS  

    Objective: To describe clinical and imaging findings of distended scapulothoracic bursitis without scapular snapping, which is often confused with a soft tissue tumor.
    Methods: Nine patients (6 male, 3 female; age range: 50-73 years; mean age = 67 years) with distended scapulothoracic bursitis diagnosed by clinical and magnetic resonance (MR) imaging findings were studied. The results of a histologic examination were available in 1 case.
    Results: All patients presented with painless palpable masses below the scapula, and the initial diagnoses were soft tissue tumors. On MR images, the lesions were 5.5 to 12 cm in maximum diameter (mean = 7.7 cm) and well-demarcated cystic masses situated in the subscapular region between the serratus anterior and the chest wall. There was no solid portion on the cyst walls. The findings of hemorrhage within the bursae were present in all cases. Every mass regressed in size spontaneously after a few to several weeks, and no lesions revealed any malignant findings of sarcomas.
    Conclusions: Distended scapulothoracic bursae without scapular snapping resemble soft tissue tumors. They have some specific MR findings; therefore, precise recognition of these findings is important to avoid misdiagnoses and unnecessary treatments.

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  • Mimics of brain tumor on neuroimaging: Part II .

    Radiat Med   22(3):135-142   2004年

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  • Mimics of brain tumor on neuroimaging: Part I.

    Radiat Med   22(2):3-7   2004年

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  • Extracerebral ectopic mass with huge cysts in the anterior cranial cavity. 査読

    Toyoshima Y, Kakita A, Yamada M, Sato G, Mori H, Okamoto K, Tanaka R, Takahashi H

    Neuropathology : official journal of the Japanese Society of Neuropathology   23 ( 4 )   301 - 306   2003年12月

  • Primary frontal-lobe germinoma appearing as a large cyst. 査読

    Kawasaki K, Yamada M, Hara N, Okamoto K, Tanaka R, Takahashi H

    Neuropathology : official journal of the Japanese Society of Neuropathology   23 ( 4 )   307 - 310   2003年12月

  • MR features of diseases involving bilateral middle cerebellar peduncles 査読

    K Okamoto, S Tokiguchi, T Furusawa, K Ishikawa, AF Quardery, S Shinbo, K Sasai

    AMERICAN JOURNAL OF NEURORADIOLOGY   24 ( 10 )   1946 - 1954   2003年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER SOC NEURORADIOLOGY  

    BACKGROUND AND PURPOSE: Distribution of lesions or involvement of specific anatomic sites can suggest the diagnosis of disease. The purpose of this study was to investigate what diseases affect both middle cerebellar peduncles (MCPs) and to evaluate other MR features for differential diagnosis.
    METHODS: MR findings of 27 patients (14 male and 13 female; age range, 4-77 years [mean, 48.5 years]) with bilateral MCP lesions were retrospectively studied.
    RESULTS: Neurodegenerative diseases were the most frequent diagnoses (n = 11 [41%]: sporadic olivopontocerebellar atrophy, eight; Shy-Drager syndrome, one; spinocerebellar ataxia, two). Also included were metabolic diseases (n = 6 [22%]: adrenoleukodystrophy, two; Wilson disease, two; cirrhosis of the liver, one; and hypoglycemia, one); cerebrovascular diseases, including posterior reversible encephalopathy syndrome (n = 3 [11%]: infarction, one; hypertensive encephalopathy, one; cyclosporin-A encephalopathy, one), demyelinating and inflammatory diseases (n = 4 [15%]: multiple sclerosis, one; acute disseminated encephalomyelitis, one; Behcet disease, one; and HIV encephalopathy, one), and neoplasms (n = 3 [11%]: lymphoma, one; glioma, one; meningeal carcinomatosis, one). All patients showed symmetrical T2 hyperintensity in both MCPs, except for one with malignant lymphoma. Marked atrophy in the posterior fossa was characteristically seen in neurodegenerative diseases. Enlargement of the pons was observed in hypertensive encephalopathy and neoplasms but absent in meningeal carcinomatosis. Lesions were restricted in the posterior fossa in eight patients with neurodegenerative diseases and one with brain stem glioma. Other patients had supratentorial lesions.
    CONCLUSION. Symmetricity of MCP lesions, morphologic change of the posterior fossa structures, and distribution of other lesions are helpful-in the differential diagnosis.

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  • Whole-blood manganese levels and brain manganese accumulation in children receiving long-term home parenteral nutrition 査読

    Y Iinuma, M Kubota, M Uchiyama, M Yagi, S Kanada, S Yamazaki, H Murata, K Okamoto, M Suzuki, K Nitta

    PEDIATRIC SURGERY INTERNATIONAL   19 ( 4 )   268 - 272   2003年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER-VERLAG  

    Recent reports attribute neurological and cerebral disorders to the accumulation of manganese (Mn) in the brain in patients receiving home parenteral nutrition (HPN). It is desirable to control the amount of Mn delivered to these patients, but a suitable method for monitoring an individual's Mn status and assessing Mn accumulation remains debatable. The aim of this study was to evaluate whether whole-blood manganese levels (WB-Mn) correlate with the accumulation of Mn in the brains of children who receive long-term HPN, using magnetic resonance imaging (MRI) of the brain. Six patients who had received HPN (duration of HPN, 18-137 months) were included in this study. The daily parenteral doses of Mn were calculated while on HPN. WB-Mn was measured and T1-weighted MRI of the brain was obtained for each patient with a 1.5-T MR imager. Twelve months after the withdrawal of Mn from HPN, measurements of WB-Mn and brain MRI were repeated in all patients except for one who was lost after initial examination. The same examinations were performed on an additional patient who had been successfully weaned off a 179 month course of HPN 20 months prior to the initial examination. The parenteral dose of Mn while receiving HPN ranged from 15.7 to 91.5 mug/kg/day. Initially, MRI showed hyperintensity in the globus pallidus in all patients and in the anterior pituitary in one patient. WB-Mn was elevated in four patients, but was in the normal range in the remaining three. Following subsequent measurements 12 months later, WB-Mn was normal in all patients and MRI hyperintensity remained in the globus pallidus in one patient. One patient was lost after the initial examinations. WB-Mn does not necessarily correlate with the accumulation of Mn in the brain. Periodic MRI should be performed in patients receiving long-term NPN to monitor for excessive Mn accumulation in the brain.

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  • Diseases involving bilateral middle cerebellar peduncles: demonstration on magnetic resonance imaging.

    AJNR Am J Neuroradiol   24(10):1954-1964   2003年

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  • Atrophy of the basal ganglia as the initial diagnostic sign of germinoma in the basal ganglia

    K Okamoto, J Ito, K Ishikawa, K Morii, M Yamada, N Takahashi, S Tokiguchi, T Furusawa, K Sakai

    NEURORADIOLOGY   44 ( 5 )   389 - 394   2002年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER-VERLAG  

    Germ-cell tumors of the central nervous system generally develop in the midline, but the tumors can also occur in the basal ganglia and/or thalamus. However, M R images have rarely been documented in the early stage of the tumor in these regions. We retrospectively reviewed MR images obtained on admission and approximately 3 years earlier in two patients with germinoma in the basal ganglia, and compared them with CT. In addition to hyperdensity on CT, both hyperintensity on T1-weighted images and a small hyperintense lesion on T2-weighted images were commonly seen in the basal ganglia. These findings may be early MRI signs of germinoma in this region, and the earliest and most characteristic diagnostic feature on MRI was atrophy of the basal ganglia, which was recognizable before development of hemiparesis.

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  • MRI of high-grade astrocytic tumors: early appearance and evolution

    K Okamoto, J Ito, N Takahashi, K Ishikawa, T Furusawa, S Tokiguchi, K Sakai

    NEURORADIOLOGY   44 ( 5 )   395 - 402   2002年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER-VERLAG  

    The clinical management and prognosis of patients with diffusely infiltrating astrocytomas are dependent on neuropathological grading of the tumors. The characteristics of MR images of high-grade astrocytic tumors are well known, but the early MRI appearance and the MRI evolution of high-grade astrocytic tumors have rarely been examined. We retrospectively reviewed MR images obtained from 4 months to 3 years and 3 months before admission, as well as MR images on admission, for five patients with pathologically proven high-grade astrocytic tumors (two glioblastomas and three anaplastic astrocytomas). In two patients, neoplastic lesions were not detectable on initial MRI, even retrospectively. In the remaining three patients, however., hyperintense areas with little or no mass effect were demonstrated on T2-weighted imaging. These lesions were misinterpreted as non-neoplastic processes, such as ischemic lesion or infarction, or demyelinating processes. All tumors showed gadolinium enhancement on admission, that emerged from the previously existing hyperintense areas on T2-weighted images without gadolinium enhancement, except for one de novo glioblastoma. Development of a small central cyst without gadolinium enhancement was demonstrated in one case before the emergence of an enhancing area.

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  • MR findings with dynamic evaluation in Riedel's thyroiditis 査読

    N Takahashi, K Okamoto, K Sakai, M Kawana, M Shimada-Hiratsuka

    CLINICAL IMAGING   26 ( 2 )   89 - 91   2002年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE INC  

    We reported the findings on MRI in a patient with proven Riedel's thyroiditis. The lesion was seen as slightly heterogeneous hypointensity on both T1- and T2-weighted images and had a mild enhancement after administration of gadpentate dimeglumine (GdDTPA). Dynamic MR study showed gradual increase in signal intensity of the lesion. These Findings were different from those of thyroid neoplasms and were considered to reflect the mixture of inflammatory cells infiltration and fibrosis of Riedel's thyroiditis. (C) 2002 Elsevier Science Inc. All rights reserved.

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  • MRI in essential primary cutis verticis gyrata.

    Neuroradiology   43(10):841-844   2001年

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  • Change in signal intensity on MRI of fat in the head of markedly emaciated patients. Neuroradiology 43(2):134-138, 2001Change in signal intensity on MRI of fat in the head of markedly emaciated patients.

    Neuroradiology   43(2):134-138 ( 1 )   134 - 138   2001年

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  • Decreased signal intensity of the middle cerebellar peduncle on diffusion-weighed MRI in patients with large spratentorial lesions.

    J Comput Asssit Tomogr   25(1):106-112 ( 1 )   106 - 112   2001年

  • The principle of digital subtraction angiography and radiological protection

    K Okamoto, J Ito, K Sakai, S Yoshimura

    INTERVENTIONAL NEURORADIOLOGY   6 ( 補遺1 )   25 - 31   2000年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:EDIZIONI CENTAURO  

    Recent improvements in x-ray technology have greatly contributed to the advancement of diagnostic imaging. Fluoroscopically guided neurointerventional procedures with digital subtraction angiography (DSA) are being performed with increasing frequency as the treatment of choice for a variety of neurovascular diseases. Radiation-induced skin injuries can occur after extended fluoroscopic exposure times, and the injuries have recently been reported. In this article, measured radiation doses at the surface of Rando Phantom with Skin Dose Monitor, and estimated and measured entrance skin doses in patients underwent neurointerventional procedures are reported as well as means of reducing radiation doses absorbed by patients and personnel to avoid occurrence of radiation-induced injuries.

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  • Solitary myofibromtosis of the skull.

    Eur Radiol   10(1):170-174   2000年

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  • CT and MR imaging of the “target sign” in metastatic brain disease.

    Eur Radiol   10 ( 1 )   154 - 156   2000年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

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  • Diffusion-weighted echo-planar MR imaging in differential diagnosis of brain tumors and tumor-like conditions

    K Okamoto, J Ito, K Ishikawa, K Sakai, S Tokiguchi

    EUROPEAN RADIOLOGY   10 ( 8 )   1342 - 1350   2000年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER-VERLAG  

    We assess diffusion-weighted MR images in the differential diagnosis of intracranial brain tumors and tumor-like conditions. Heavily diffusion-weighted (b = 1100 or 1200 s/mm(2)) axial images were obtained with single-shot echo-planar technique in 93 patients with pathologically confirmed various intracranial tumors and tumor-like conditions with diffusion gradient perpendicular to the images. We compared signal intensity of the lesions with those of gray and white matter, and cerebrospinal fluid (CSF). In 29 cases (31.1 %) the lesions were isointense to gray and/or white matter. However, 5 cases (5.4 %) showed extremely increased signal intensity: two epidermoid cysts; two chordomas; and one brain abscess. The entire portion of a tumor was markedly hyperintense in 10 cases (10.8 %): four malignant lymphomas; four medulloblastomas; one germinoma; and one pineoblastoma. A CSF-like hypointense signal was seen in many cystic tumors, and cystic or necrotic portions of tumors. A neurosarcoid granulation was the only solid lesion showing characteristically a hypointense signal like CSF. The combination of markedly hyperintense and hypointense signals was seen generally in hemorrhagic tumors. Diffusion-weighted echo-planar MR imaging is useful in the differential diagnosis of brain tumors and tumor-like conditions, and suggests specific histological diagnosis in some cases.

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  • Imaging of calvarial eosinophil granuloma

    K Okamoto, J Ito, T Furusawa, K Sakai, S Tokiguchi

    NEURORADIOLOGY   41 ( 10 )   723 - 728   1999年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER VERLAG  

    We reviewed the imaging of four pathologically proven calvarial eosinophil granulomas. The diameter of the lesions ranged from 13 to 40 mm; three were biconvex, but the other had a collar-stud appearance. Two lesions were in the frontal and two in the parietal bone. On bone-window CT, a bevelled edge was seen in three cases and button sequestration in one, but no sclerotic rim was shown. Although one lesion had a low-density area, the lesions were slightly denser than grey matter. They were isointense with grey or white matter on T1-weighted MRI and gave heterogeneous high signal on proton-density and T2-weighted images. All enhanced markedly, with a less strongly enhancing portion within them. A tail of dural enhancement and reactive change in the overlying galea or temporal muscle were seen in all cases.

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  • Cicatricial fibromatosis mimics metastatic medulloblastoma

    K Okamoto, J Ito, K Sakai

    AMERICAN JOURNAL OF NEURORADIOLOGY   20 ( 3 )   472 - 473   1999年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER SOC NEURORADIOLOGY  

    Cicatricial fibromatoses usually occur in the anterior abdominal wall or in the extremities, but rarely in the scalp or the soft tissues of the neck. We report a case of desmoid fibromatosis that developed in a 15-year-old boy 8 months after surgery for cerebellar medulloblastoma.

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  • Bilateral optic neuritis in a child diagnosed with Gd-enhanced MR imaging using fat-suppression technique

    K Okamoto, J Ito, R Ogawa, T Furusawa, K Sakai, S Tokiguchi, M Takagi

    EUROPEAN RADIOLOGY   9 ( 4 )   731 - 733   1999年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER VERLAG  

    A 4-year-old boy developed bilateral optic neuritis. Although precise neuro-ophthalmological evaluation was difficult, the diagnosis was made with gadolinium-enhanced MR imaging using fat-suppression technique in the initial stage of the disease. Enhancement and enlargement of the intraorbital and intracanalicular optic nerve were demonstrated bilaterally as well as protrusion of the optic nerve head. The disease responded dramatically to intravenous steroid therapy. The etiologies in children usually differ from those in adolescent and adult patients.

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  • Small cortical infarcts mimicking metastatic tumors

    K Okamoto, J Ito, T Furusawa, K Sakai, M Watanabe, S Tokiguchi

    CLINICAL IMAGING   22 ( 5 )   333 - 338   1998年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE INC  

    Small cortical enhancing lesions mimicking metastases were demonstrated on contrast imaging in three patients without specific neurologic deficits corresponding to the lesions. One patient had a lung carcinoma. However, all had cardiac arrhythmias known as major sources of cerebral emboli. Two had early cerebral infarcts and ischemic heart diseases. The lesions disappeared spontaneously on follow-up studies. They were subsequently presumed to be small infarcts. Clinical information and follow-up examinations are important to differentiate these small cortical lesions from metastases, (C) Elsevier Science Inc., 1998.

    DOI: 10.1016/S0899-7071(98)00025-4

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  • Reversible hyperintensity of the anterior pituitary gland on T1-weighted MR images in a patient receiving temporary parenteral nutrition

    K Okamoto, J Ito, T Furusawa, K Sakai, S Tokiguchi

    AMERICAN JOURNAL OF NEURORADIOLOGY   19 ( 7 )   1287 - 1289   1998年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER SOC NEURORADIOLOGY  

    We report a patient with severe anorexia nervosa, treated with temporary total parenteral nutrition (TPN), in whom reversible hyperintensity of the anterior pituitary gland was seen on T1-weighted MR images. The anterior pituitary was isointense with white matter before TPN therapy and became markedly hyperintense after 3 months of treatment. The intensity normalized after TPN therapy was discontinued. The transient hyperintensity was also seen in the basal ganglia and dorsal brain seem. We believe the hyperintensity of the anterior pituitary may be attributed to the TPN therapy.

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  • MRI of enlarged endolymphatic sacs in the large vestibular aqueduct syndrome

    K Okamoto, J Ito, T Furusawa, K Sakai, S Horikawa, S Tokiguchi

    NEURORADIOLOGY   40 ( 3 )   167 - 172   1998年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER VERLAG  

    We studied ten inner ears of five patients with a bilateral large vestibular aqueduct syndrome, using CT and MRI. Although the large vestibular aqueduct varied in size, a markedly dilated endolymphatic sac extending to the sigmoid sinus was demonstrated bilaterally on MRI in all patients. The cause of hearing loss in this syndrome is unclear. However, it is suggested that reflux of the protein-rich, hyperosmolar endolymph from the enlarged endolymphatic sac (EES) into the cochlea through a widely patent endolymphatic duct may damage the neuroepithelium. CT density and spin-echo MRI signal intensity of the endolymph in EES were markedly higher than those of CSF in eight inner ears of four patients. Increased density and high signal may indicate protein-rich, hyperosmolar endolymph. In some patients with sensorineural hearing loss and EES, the vestibular aqueduct may not appear dilated on CT. MRI is therefore necessary for correct diagnosis of this syndrome, which should more correctly be termed "large endolymphatic duct and sac syn drome". Prominent EES may prediet poor prognosis in this syndrome.

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  • Focal orbital amyloidosis presenting as rectus muscle enlargement: CT and MR findings.

    AJNR Am J Neuroradiol   19(9):1799-1801   1998年

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  • ''Pseudoocclusion'' of the internal carotid artery: A pitfall on intracranial MRA

    K Okamoto, J Ito, T Furusawa, K Sakai, S Tokiguchi

    JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY   21 ( 5 )   831 - 833   1997年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:LIPPINCOTT-RAVEN PUBL  

    We report a case showing ''pseudoocclusion'' of the internal carotid artery as a pitfall on intracranial MRA. Pseudoocclusion was attributed to magnetic susceptibility artifacts with metallic substances located proximal to a slab. The same finding could be reproduced on experimental MRA with a small steel coil applied on the anterior neck of a volunteer at the level of the carotid bifurcation.

    DOI: 10.1097/00004728-199709000-00033

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  • Solitary plasmacytomas of the occipital bone: A report of two cases

    K Okamoto, J Ito, T Furusawa, K Sakai, S Tokiguchi, M Sato, R Tanaka, K Nemoto, K Oyanagi

    EUROPEAN RADIOLOGY   7 ( 4 )   503 - 506   1997年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER VERLAG  

    The radiological appearances of two cases of solitary plasmacytoma in the occipital bone are described. One arose in the lateral part and the other in the squama. They showed characteristic radiological features on CT, MRI and angiography. Bone scintigraphy and gallium scintigraphy were also available. Solitary plasmacytoma of the skull is a rare condition and usually occurs in the calvarium. The skull base is an extremely rare site and only four cases have been reported. The literature of solitary plasmacytoma of the skull is reviewed.

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  • Arachnoid granulations of the posterior fossa: CT and MR findings

    K Okamoto, J Ito, S Tokiguchi, T Furusawa, M Nishihara

    CLINICAL IMAGING   21 ( 1 )   1 - 5   1997年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE INC  

    The radiological appearance of typically located arachnoid granulations on craniograms is well known. Arachnoid granulations of unusual size and location should be distinguished from pathological processes, We analyzed six patients with arachnoid granulations in the posterior fossa. Characteristic findings of arachnoid granulations were disclosed by computed tomography (CT) and magnetic resonance (MR) imaging; a punched out-like bone defect from the inner table into the outer fable on CT scans and intensify similar to that of the cerebrospinal fluid in all pulse sequences on MR images. (C) Elsevier Science Inc., 1997.

    DOI: 10.1016/0899-7071(95)00093-3

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  • Atrophy of Bilateral Extraocular Muscles, CT and Clinical Features of Seven Patients.

    J Neuro-Ophthalmol   16(4):286-288   1996年

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  • High-Resolution CT Findings in the Development of the Sphenooccipital Synchondrosis.

    AJNR Am J Neuroradiol   17(1):117-120 ( 1 )   117 - 120   1996年

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  • Peculiar enlargement of the nasopharynx in patients with anorexia nervosa

    K Okamoto, J Ito, S Tokiguchi, G Kuwabara, M Nishihara

    NEURORADIOLOGY   37 ( 8 )   674 - 678   1995年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER VERLAG  

    We examined the nasopharynx and brain in 17 patients with anorexia nervosa by CT and compared the findings with those of 44 normal subjects and of 5 patients of the same age with marked emaciation caused by various psychiatric disorders. An enlarged nasopharyngeal space with a flattened posterior wall and enlarged lateral pharyngeal recesses were demonstrated in all patients with anorexia nervosa whose weight was lowest at the time of the CT examination, and these CT features regressed or became normal quickly after they had gained some weight. This characteristic en largement of the nasopharynx and lateral pharyngeal recesses was observed neither in the markedly emaciated patients (2 with schizophrenia, 1 with major depression, 1 with stupor and the other with an extremely unbalanced diet) nor in 44 normal subjects without emaciation. These features were therefore thought to be characteristic and of diagnostic significance.

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書籍等出版物

  • 新版 これでわかる拡散MRI: 総論、類表皮嚢腫、悪性リンパ腫,髄芽腫、髄膜腫、胚腫,血管芽腫、転移性脳腫瘍、その他の脳腫瘍・脳腫瘍類似疾患、嚢胞性病変の鑑別への応用.

    秀潤社  2005年 

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  • 頭部画像診断のここが鑑別ポイント.脳腫瘍:014膠芽腫、015退形成性星細胞腫、016びまん性星細胞腫、017大脳膠腫症、018毛様細胞性星細胞腫、019多形黄色星細胞腫、020乏突起膠腫、021上衣腫、022神経節膠腫.

    羊土社  2005年 

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  • Supratentorial tumors

    1999年 

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  • MRI-最近の進歩(共著)

    Annual Review 神経 1999  1999年 

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  • テント上腫瘍

    脳脊髄のMRI  1999年 

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  • 頭部MRI検査における基準線の決め方-orbitomeatal lineとReid's base line

    臨床放射線科のコツと落とし穴 検査・診断Part1  1999年 

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  • 小児の大きな側脳室三角部腫瘍

    フィルムソーディング1 脳・脊髄  1998年 

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  • 小児の大きな第3脳室腫瘍(共著)

    フィルムリーディング1 脳・脊髄  1998年 

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  • Brain Tumors

    Textbook of Radiology  1997年 

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  • 脳腫瘍

    放射線科学[診断]  1997年 

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  • 脳腫瘍?(共著)

    1995年 

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  • 嗅溝部類上皮腫?

    一筋縄ではいかなかった中枢神経の画像診断  1995年 

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  • 頭蓋骨

    TEXT 放射線医学  1994年 

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  • 1.頭部単純写真 2.正常頭部単純写真 3.頭部単純写真における正常所見 4.頭部単純写真における異常所見

    内科診断学  1994年 

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  • 脊髄

    TEXT 放射線医学  1994年 

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  • 脳血管障害

    TEXT 放射線医学  1994年 

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▶ 全件表示

MISC

  • 脳腫瘍の画像診断:概論. ,

    日本臨床   63, suppl 9, 207-211   2005年

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  • 脳腫瘍を疑ったとき

    medicinea   42(3):466-168   2005年

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  • 良悪性境界病変の画像診断:脳腫瘍.:疾患概念と画像診断.

    臨床画像   20(12):1344-1355   2004年

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  • 拡散強調像(DWI)による頭蓋内占拠性病変定性診断.

    脳神経外科速報   14(4):385-390   2004年

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  • ちょっとハイレベルの日常遭遇する脳疾患—知っているとMRI読影が楽しくなる情報— 炎症性疾患 症例1〜9.

    画像診断   24(3):304-321   2004年

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  • 軽度アルツハイマー型痴呆における客観的診断の可能性

    児玉 直樹, 島田 哲雄, 歸山 智治, 金子 智之, 小林 嘉雄, 川瀬 康裕, 岡本 浩一郎, 福本 一朗

    日本医用画像工学会雑誌   21:281-285 ( 4 )   281 - 285   2003年

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    記述言語:日本語   出版者・発行元:日本医用画像工学会  

    DOI: 10.11409/mit.21.281

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    その他リンク: http://search.jamas.or.jp/link/ui/2004083993

  • 造影MRIのメルクマール-Contrast Enhanced MR Angiography- 3. 頸部.

    INNERVISION   18(4):92-97   2003年

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  • 画像診断でここまで分かる-各診断法の特徴-脳腫瘍

    癌の臨床   49(9):893-898   2003年

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  • 血栓化により自然退縮した、急性膵炎に伴う膵仮性動脈瘤の1例.

    臨放   48(8):996-999   2003年

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  • 神経放射線は難しくない: 基本的知識へのアプローチ「脳血管障害・血管性病変

    画像診断   22(11):1201-1210   2002年

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  • 頭部MR画像を用いたアルツハイマー型痴呆客観的診断法の基礎研究.

    MEとバイオサイバネティクス研究会 信学技報MBE2000-53-66   100(330): 17-22   2002年

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  • Multidetector row CTを用いた披裂軟骨・輪状軟骨のVolume rendering法による三次元表示の有用性

    高橋 直也, 岡本 浩一郎, 酒井 邦夫, sakai Kunio, Takahashi Naoya, Okamoto Kouichirou, オカモト コウイチロウ, タカハシ ナオヤ, サカイ クニオ

    日本医学放射線学会雑誌   61 ( 6 )   310 - 311   2001年

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    記述言語:日本語   出版者・発行元:日本医学放射線学会  

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  • Symptomatic Child Case of Subependymoma in the Fourth Ventricle without Hydrocephalus(共著)

    Radiation Medicine   19 ( 1 )   37 - 42   2001年

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  • Multidetector row CTを用いた披裂軟骨・輪状軟骨のVolume rendering法による三次元表示の有用性

    高橋 直也, 岡本 浩一郎, 酒井 邦夫, sakai Kunio, Takahashi Naoya, Okamoto Kouichirou, オカモト コウイチロウ, タカハシ ナオヤ, サカイ クニオ

    日本医学放射線学会雑誌   61 ( 6 )   310 - 311   2001年

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    記述言語:日本語   出版者・発行元:日本医学放射線学会  

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  • Band-suppressed restoration of X-ray images blurred by body movement

    J Hori, Y Saitoh, T Kiryu, K Okamoto, K Sakai

    METHODS OF INFORMATION IN MEDICINE   39 ( 2 )   130 - 133   2000年6月

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    記述言語:英語   出版者・発行元:SCHATTAUER GMBH-VERLAG MEDIZIN NATURWISSENSCHAFTEN  

    The restoration of X-ray images that have been blurred due to body movement are discussed. The observation system for these images is described using a mathematical model, and several restoration filters composed of a series of such models are proposed. These filters restore band-suppressed approximations of the original images. In addition, redundancy is introduced into these restoration filters in order to suppress additive noise. These filters are expanded to be applicable not only to parallel translations, but also to rotations by coordinate transformation. The proposed methods are applied to blurred X-ray images of a bone model of the elbow joint. The parameters of the restoration filter are estimated using a marker attached to the subject as a reference signal.

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  • IVRにおける被曝と放射線防護, 神経放射線領域を中心に

    岡本 浩一郎, 吉村 秀太郎, 岡 哲也

    臨床放射線   45 ( 12 )   1495 - 1503   2000年

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    記述言語:日本語   出版者・発行元:金原出版  

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    その他リンク: http://search.jamas.or.jp/link/ui/2001097074

  • 乳頭浮腫を指摘された患者のMRI診断

    日本磁気共鳴医学会雑誌   20 ( 8 )   390 - 393   2000年

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  • 3. 脊椎 : 腫瘍、椎間板ヘルニア, その他(共著)

    インナービジョン   15 ( 4 )   34 - 42   2000年

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  • ミトコンドリア糖尿病の頭部CT所見(共著)

    CI研究   22 ( 3 )   193 - 197   2000年

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  • 神経内科領域におけるMRI/MRAの最新動向(共著)

    中田力

    神経内科   53 ( 3 )   219 - 226   2000年

  • Solitary myofibromatosis of the skull

    K Okamoto, J Ito, H Takahashi, Emura, I, H Mori, T Furusawa, K Sakai, T Higuchi, S Tokiguchi

    EUROPEAN RADIOLOGY   10 ( 1 )   170 - 174   2000年

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    記述言語:英語   出版者・発行元:SPRINGER VERLAG  

    We present a case of solitary infantile myofibromatosis of the skull in a 3-month-old boy. A right parietal subcutaneous lump was found at birth. and it increased in size over the ensuing 3 months. Surgery was performed, and a diagnosis of myofibromatosis was confirmed histopathologically. Solitary myofibromatosis of the skull is extremely rare. The radio-graphical, CT, and MR appearances, as well as histopathological findings, are described in this article.

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  • Radiation exposure and radiological protection in interventional radiological procedures with special attention to neurointerventional Radiology

    Japanese Journal of Clinical Radiology   45 ( 12 )   1495 - 1503   2000年

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  • MR imaging of a patient with papilledema

    Japanese Journal of Magnetic Resonance in Medicine   20 ( 8 )   390 - 393   2000年

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  • 3. Spine : Tumors, Disk hernia, and others

    INNERVISION   15 ( 4 )   34 - 42   2000年

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  • CT findings of Diabetes Mellitus Associated with A Mutation of Mitochondrial DNA

    Progress in Computed Imaging   22 ( 3 )   193 - 197   2000年

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  • MRI/MRA

    Neurological Medicine   53 ( 3 )   219 - 226   2000年

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  • MRIにおける上咽頭腫瘤の鑑別診断(共著)

    高橋 直也, 岡本 浩一郎, 木村 元政, 酒井 邦夫, 野々村 直文, 川崎 俊彦

    臨床放射線   44 ( 9 )   993 - 999   1999年

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    記述言語:日本語   出版者・発行元:金原出版(株)  

    上咽頭腫瘤性病変のMR像を検討した.特に,腫瘍と鑑別が必要なアデノイドにおいて,隔壁様線状造影効果に加えて,T2強調像における点状高信号が高率に認められ,鑑別診断上有用であった

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  • Focal orbital amyloidosis presenting as rectus muscle enlargement : CT and MR findings

    American Journal of Neuroradiology   19 ( 9 )   1799 - 1801   1999年

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  • Differential diagnosis of nasopharyngeal masses on MR imaging

    Japanese Journal of Clinical Radiology   44 ( 9 )   993 - 999   1999年

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  • Serial cerebral computed tomography and magnetic resonance imaging in a case of hemolytic uremic syndrome with the complication of the central nervous system due to Escherichia coli O157 : H7

    N. Akasaka, H. Hayakawa, T. Okugawa, T. Kasahara, N. Ishikawa, M. Tojo, K. Okamoto, M. Uchiyama

    No To Hattatsu   31 ( 6 )   565 - 570   1999年

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    記述言語:日本語  

    We report serial cerebral computed tomography (CT) and magnetic resonance imaging (MRI) in a case of hemolytic uremic syndrome (HUS) with the complication of the central nervous system due to Escherichia coli O157 : H7. Although initial brain CT was normal, follow-up CT and MRI revealed lesions in the white matter and bilateral basal ganglia, representing brain edema and infarcts, respectively. Especially, lesions in the bilateral basal ganglia were very unique. Serial CT and MRI findings are useful to understand the mechanism of the complications of the central nervous system associated with HUS.

    DOI: 10.11251/ojjscn1969.31.565

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  • 腸管出血性大腸菌O-157感染により溶血性尿毒症症候群と中枢神経病変を呈した1例における頭部CT,MRIの推移(共著)

    赤坂紀幸, 早川広史, 奥川敬祥, 笠原多加幸, 石川憲夫, 東条恵, 岡本浩一郎, 内山聖

    脳と発達   31 ( 6 )   565 - 570   1999年

  • 口腔癌所属リンパ節の初期転移巣の画像診断精度に関する基礎的研究

    インナービジョン   13 ( 9 )   53   1998年

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  • Quiz case of the month, deep cerebral vein thrombosis

    European Radiology   8 ( 2 )   319 - 320   1998年

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  • CT and MR findings of neuroacanthocytosis

    K Okamoto, J Ito, T Furusawa, K Sakai, S Tokiguchi, A Homma, R Koike, S Tsuji

    JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY   21 ( 2 )   221 - 222   1997年3月

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    記述言語:英語   出版者・発行元:LIPPINCOTT-RAVEN PUBL  

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  • Large vestibular aqueduct syndrome with high CT density and high MR signal intensity

    K Okamoto, J Ito, T Furusawa, K Sakai, S Tokiguchi

    AMERICAN JOURNAL OF NEURORADIOLOGY   18 ( 3 )   482 - 484   1997年3月

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    記述言語:英語   出版者・発行元:AMER SOC NEURORADIOLOGY  

    We report a case of large vestibular aqueduct syndrome with a markedly dilated endolymphatic sac bilaterally. The density and signal intensity of the extraosseous portion of the sac were higher than those of cerebrospinal fluid on CT and MR studies. The findings may represent protein-rich and hyperosmolar fluid within the endolymphatic sac.

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  • 磁気共鳴画像(MRI)(共著)

    臨床検査   41 ( 11 )   1472 - 1476   1997年

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  • 画像でわかる脳腫瘍の性状

    画像診断   17 ( 12 )   1267 - 1276   1997年

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  • Imaging characteristics of brain tumors

    Japanese Journal of Diagnostic Imaging   17 ( 12 )   1267 - 1276   1997年

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  • CT and MR Findings of Neuroacanthocytosis.

    J Comput Assist Tomogr   21(2):221-222   1997年

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  • Large Vestibular Aqueduct Syndrome with High CT Density and High MR Signal Intensity.

    AJNR Am J Neuroradiol   18(3):482-484   1997年

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  • Intratumoral flow void in pituitary adenomas

    K Okamoto, J Ito, T Furusawa, K Sakai

    AMERICAN JOURNAL OF ROENTGENOLOGY   167 ( 4 )   1070 - 1071   1996年10月

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    記述言語:英語   掲載種別:速報,短報,研究ノート等(学術雑誌)   出版者・発行元:AMER ROENTGEN RAY SOC  

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  • Development of fat within a meningioma

    K Okamoto, J Ito, S Tokiguchi, T Furusawa, S Yoshida, R Tanaka, K Iwanaga, K Oyanagi

    NEURORADIOLOGY   38 ( 3 )   214 - 216   1996年4月

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    記述言語:英語   出版者・発行元:SPRINGER VERLAG  

    We report a tentorial meningioma containing fat, Multiple areas of fatty density or intensity in the tumour were seen on CT and MRI, which corresponded histologically to lipomatous components. CT 10 years previously had demonstrated a smaller tumour without evidence of fatty components. We found only five cases in the literature in which fatty density was demonstrated within a meningioma on CT and a lipomatous component histologically proved. Xanthomatous change, with lipid in tumour CT. but not to the levels of fat. As both lipomatous components and xanthomatous change show similar intensity on MRI, CT can be helpful in differentiating these two conditions. To our knowledge, our case is the only one in which the advent of fatty tissue was confirmed during follow-up.

    DOI: 10.1007/s002340050232

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  • 出血で発症し画像上海線状血管腫が疑われた微小神経膠腫の1例(共著)

    脳神経外科速報   6 ( 11 )   849 - 854   1996年

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  • Atrophy of bilateral extraocular muscles

    Journal of Neuro-Ophthalmology   16 ( 4 )   286 - 288   1996年

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  • Development of fat within a meningioma.

    Neuroradiology   38(3):214-216   1996年

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  • A case of small glioma presenting with hemorrhage mimicking cavernous angioma on imaging studies

    Neurosurgery Letters   6 ( 11 )   849 - 854   1996年

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  • 歯および顎骨(共著)

    臨床画像   12 ( 5 )   514 - 520   1996年

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  • Intractable hiccups observed in multiple sclerosis.

    Neurological Medicine   42 ( 3 )   273 - 275   1995年

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  • A case of chordoma in the petrous bone

    Japanese Journal of Clinical Radiology   40 ( 5 )   609 - 612   1995年

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  • A case of supratentorial and posterior fossa hemangio-blastomas.

    Japanese Journal of Clinical Radiology   40 ( 8 )   941 - 944   1995年

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  • 難治性吃逆を主訴とした多発性硬化症(共著)

    神経内科   42 ( 3 )   273 - 275   1995年

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  • 側頭骨錐体尖部に発生した脊索腫の1例(共著)

    臨床放射線   40 ( 5 )   609 - 612   1995年

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  • 天幕上および天幕下に認められた血管芽細胞腫の1例(共著)

    臨床放射線   40 ( 8 )   941 - 944   1995年

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  • 塞栓療法を行った血管腫の2例-術前血管造影所見と塞栓療法の効果の関連について-(共著)

    松下 健, 岡本 浩一郎, 大橋 靖, 成 辰煕, 星名 秀行, 森山 万紀子

    日本口腔科学会雑誌   44 ( 3 )   491 - 495   1995年

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    記述言語:日本語   出版者・発行元:Japanese Stomatological Society  

    Two cases of giant hemangioma of oral region treated by transcatheter embolization are reported in this article.<BR>Case one was a 2I-year-old female visited our hospital complaining of swelling of the tongue and oral floor. External carotid angiography showed a vascular lesion mostly fed by the bilateral facial arteries, and showed clear tumor stain. Transcatheter embolization using Ivalon® was carried out with digital subtraction angiography. After embolization the tumor stain and the distal parts of main feeders were not visualized on angiography, and then the tumor size was decreased clearly.<BR>Case two was a 25-year-old man, who came to our hospital complaining of speech disturbance due to swelling of the tongue. ECAG showed a vascular lesion fed by the left lingual artery, but tumor stain was not visualized. We tried transcatheter embolization without excising the tumor, taking into consideration of the functional aspects. After embolization, the distal part of the main feeder was not demonstrated. After treatment, a considerable decrease in the size of the lesion was observed.<BR>From these experiences, it was considered that embolization was one of treatment methods of the hemangioma of oral and maxillofacial regions, and that angiography gave many informations about its indication and effect.

    DOI: 10.11277/stomatology1952.44.491

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