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Dive into the research topics where Shinji Ohba is active.

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Featured researches published by Shinji Ohba.


Neurosurgical Review | 2007

Expression of vascular endothelial growth factor in dura mater of patients with moyamoya disease

Shigeyuki Sakamoto; Yoshihiro Kiura; Fumiyuki Yamasaki; Masaaki Shibukawa; Shinji Ohba; Prabin Shrestha; Kazuhiko Sugiyama; Kaoru Kurisu

Vascular endothelial growth factor (VEGF) has been found to be involved in vasculogenesis in different intracranial lesions. We investigated meningeal cellularity and VEGF expression in dura mater of patients with and without moyamoya disease. Nine dural specimens from nine cerebral hemispheres of seven patients with moyamoya disease and four control dural specimens from four non-moyamoya patients were collected during surgery and investigated. Dural specimens were immunohistochemically stained with VEGF antibody, and then meningeal cellularity and VEGF expression in dural tissue were analyzed. The mean ± standard error (SE) of total number of meningeal cells (meningeal cellularity) in dural tissue was 21.5 ± 3.0 in the moyamoya disease patients, whereas it was 2.7 ± 0.7 in control patients. The mean ± SE of VEGF expression was 51.1 ± 4.9% in the moyamoya disease patients, whereas it was 13.8 ± 5.9% in control patients. The meningeal cellularity and VEGF expression were statistically significantly higher in the moyamoya group in comparison to control group (p < 0.0001). Meningeal cellularity and VEGF expression are significantly increased in dura mater of the patients with moyamoya disease.


Journal of Trauma-injury Infection and Critical Care | 1995

Steal phenomenon in a traumatic carotid-cavernous fistula.

Koji Iida; Tohru Uozumi; Kazunori Arita; Toshinori Nakahara; Shinji Ohba; Hideki Satoh

A patient with head injury presented with computed tomography findings of a diffuse severe infarction of the left cerebral hemisphere in which the cerebral hemodynamics can be evaluated by transcranial Doppler sonography. Serial angiograms revealed a carotid-cavernous fistula, with a complete steal phenomenon. The unusual complication of a traumatic carotidcavernous fistula is discussed.


Acta Neurochirurgica | 2006

CT perfusion imaging for childhood moyamoya disease before and after surgical revascularization

Shigeyuki Sakamoto; Shinji Ohba; Masaaki Shibukawa; Yoshihiro Kiura; Kazunori Arita; Kaoru Kurisu

SummaryMoyamoya disease is a progressive occlusive disease of the circle of Willis with prominent collateral arterial formation. We report on a 12-year-old girl with moyamoya disease presenting with transient ischemic attacks (TIAs). Surgical indirect revascularization was performed. The patient did not suffer further TIAs at 12 month follow-up. Pre and postoperative cerebral perfusion were studied in quantitative single photon emission computerized tomography (SPECT) and CT perfusion imaging. CT perfusion imaging demonstrated postoperatively increased cerebral blood flow as well as SPECT before and after revascularization. Furthermore, the area of decreased vascular reserve in SPECT with acetazolamide corresponded to areas of increased cerebral blood volume in CT perfusion imaging. CT perfusion imaging was equivalent to SPECT in accuracy, and superior in spatial resolution. CT perfusion imaging is likely to become more widely available as an easy-to-perform technique for assessing cerebral perfusion in a patients with moyamoya disease.


Clinical Neurology and Neurosurgery | 2005

Churg-Strauss syndrome presenting with subarachnoid hemorrhage from ruptured dissecting aneurysm of the intracranial vertebral artery

Shigeyuki Sakamoto; Shinji Ohba; Kuniki Eguchi; Masaaki Shibukawa; Yoshihiro Kiura; Takahito Okazaki; Yohsuke Kajihara; Kazunori Arita; Kaoru Kurisu

Churg-Strauss syndrome (CSS) represents a rare systemic vasculitis that is almost invariably accompanied by bronchial asthma and eosinophilia. We report a case of a 36-year-old woman with previously diagnosed CSS presented with subarachnoid hemorrhage (SAH) from dissecting aneurysm in a vertebral artery (VA). Two months before onset of SAH, the patient had presented with numbness on her right lower leg due to peripheral neuropathy. On admission, angiography revealed dissecting aneurysm of the right intracranial VA and stenosis of the basilar artery. Hematological examination revealed an increased percentage of eosinophils. Ruptured dissecting aneurysm of the intracranial VA was diagnosed. Emergent coil embolization of the dissecting aneurysm and occlusion of the parent artery was performed to prevent repeated hemorrhage from the dissecting aneurysm. Then pharmacotherapy with prednisone was initiated for CSS. The patient recovered well and was discharged without any neurological deficit. As far as we know, this is the first reported case of CSS presented with SAH from dissecting aneurysm on posterior circulation.


Surgical Neurology | 1993

Cerebral circulation in moyamoya disease: A clinical study using transcranial doppler sonography

Zainal Muttaqin; Shinji Ohba; Kazunori Arita; Toshinori Nakahara; Basant Pant; Tohru Uozumi; Satoshi Kuwabara; Shuichi Oki; Kaoru Kurisu; Takashi Yano

Transcranial Doppler sonography was performed on eight patients diagnosed as Moyamoya disease. Angiographically, the patients-four adults (mean age 42) and four children (mean age 7.7)-underwent a complete six- or five-vessel angiographic study. The results showed the following: (1) Despite the presence of stenosis, all middle cerebral arteries showed very low-flow velocity compared to their ipsilateral distal internal carotid arteries. In adult cases, the difference was very significant (p < 0.02). (2) Relatively high-flow velocity was observed in the posterior cerebral arteries of children, and in the ophthalmic arteries of adult cases. (3) In several occasions, very low-flow velocity values were still detected despite the fact that with angiography, the respective arterial segments were hardly opacified. The relation and discrepancy between these results and the angiographic findings, and the potential application of transcranial doppler in assessing and grading the severity of moyamoya disease are discussed.


Clinical Neurology and Neurosurgery | 2008

Course of apparent diffusion coefficient values in cerebral edema of dural arteriovenous fistula before and after treatment.

Shigeyuki Sakamoto; Shinji Ohba; Masaaki Shibukawa; Yoshihiro Kiura; Takahito Okazaki; Kaoru Kurisu

Apparent diffusion coefficient (ADC) values at magnetic resonance imaging (MRI) are useful to distinguish vasogenic and cytotoxic edema due to cerebovascular diseases. Dural arteriovenous fistulas (DAVFs) with retrograde leptomeningeal venous drainage may cause cerebral edema by venous congestion. We report herein the course of ADC values of cerebral edema before and after endovascular treatment in DAVFs. A 65-year-old woman with transverse-sigmoid (T-S) sinus DAVFs with retrograde leptomeningeal venous drainage presented with severe edema in cerebellar hemisphere and brainstem. In preoperative MRI, increased ADC values were observed in the edema area. The isolated sinus was obliterated completely by transvenous embolization. On the following day after treatment, the ADC values in cerebral edema area increased slightly without any new neurological deficits and improved at 1 week later. Rapid resolution of venous congestion due to DAVFs may cause a slight, transient progression of vasogenic edema.


Journal of Clinical Neuroscience | 2007

Single-stage operation for a giant haemangiopericytoma following intracranial feeder embolization

Toshinori Matsushige; Mitsuo Nakaoka; Kaita Yahara; Katsuhiro Shinagawa; Hideyuki Ohnuma; Masaaki Shibukawa; Shinji Ohba; Kaoru Kurisu

Meningeal haemangiopericytomas (HPC) are malignant intracranial neoplasms that commonly recur and metastasize. Large size at diagnosis, abundant intracranial feeders and the risk of intraoperative bleeding can make them difficult to completely remove in one operation. We report here a rare case of a giant HPC which was treated successfully using a one-stage operation following superselective intracranial feeder occlusion. A 30-year-old man presented with a left middle cranial fossa tumour extending to the left temporal lobe and cerebellar tentorium. Angiography revealed supply from a dilated left posterior temporal artery branching from the posterior cerebral artery. The tumour was totally removed in a single-stage excision after embolization of the intracranial major feeding artery. The present case suggests the usefulness of preoperative embolization for HPC, particularly of intracranial feeders, to achieve total resection safely in a single operation.


Surgical Neurology | 2003

De novo distal posterior cerebral artery aneurysm.

Hiroyuki Yoshioka; Takuhiro Hotta; Eiji Taniguchi; Naomi Hashimoto; Yasuyuki Kinoshita; Shinji Ohba; Kazunori Arita; Kaoru Kurisu

BACKGROUND De novo aneurysms in the posterior circulation are very rare. The authors describe a first case of ruptured de novo posterior cerebral artery (PCA) aneurysm in the P3 portion. CASE DESCRIPTION A 52-year-old woman with ruptured de novo P3 aneurysm was treated by early endovascular obliteration using Guglielmi Detachable Coils (GDC). To prevent vasospasm, she received postoperative treatment with a hypertensive hypervolemia dilution and a calcium antagonist. She was discharged without neurologic deficits. CONCLUSIONS Aneuryms arising from peripheral segment of PCA are rare, and delayed surgical clipping has been recommended for these lesions. This is the first report of a de novo P3 ruptured aneurysm treated by endovascular embolization using GDC in the acute stage of subarachnoid hemorrhage. The characteristics of de novo posterior circulation aneurysms and the strategy for the distal PCA aneurysms are discussed.


Neurosurgery | 2011

Mirror-image spinal dural arteriovenous fistulas at the craniocervical junction: case report and review of the literature.

Jumpei Oshita; Satoshi Yamaguchi; Shinji Ohba; Kaoru Kurisu

BACKGROUND AND IMPORTANCE We report an extremely rare case with mirror-site spinal dural arteriovenous fistulas (DAVFs) at the craniocervical junction. Although multiple spinal DAVFs have been reported in the literature, complete mirror-site lesions with fistulas and feeding arteries in the symmetric position have not been previously described. CLINICAL PRESENTATION A 74-year-old man presented with walking disturbance, urinary incontinence, and constipation progressing over a 14-month period. T2-weighted magnetic resonance imaging showed a high-intensity area in the spinal cord at the level from C4 to C6 and multiple flow voids at the surface of the spinal cord. Three-dimensional computed tomographic angiography revealed bilateral DAVFs located in the mirror site of the craniocervical junction. Direct surgery with suboccipital craniectomy and C1 laminectomy revealed dilated tortuous red veins on the dorsal surface of the spinal cord. We found bilateral symmetric red veins around the dural penetration of the vertebral artery. Both red veins were successfully interrupted with the aneurysmal clips. Postoperative 3-dimensional computed tomographic angiography revealed a disappearance of the bilateral fistulas. Magnetic resonance images obtained 6 months after the surgery confirmed the disappearance of the intramedullary high-intensity area and flow voids. The symptoms before the operation improved after surgery, especially urinary incontinence and constipation, with slight walking disturbance. CONCLUSION Because fistulas in the present case existed at the same spinal level, we found multiple fistulas on the first examination. This early notification resulted in a good outcome from the first operation. If patients with spinal DAVFs have rapidly progressing symptoms, one should suspect multiple fistulas. ABBREVIATIONS DAVF: dural arteriovenous fistula


Surgical Neurology | 2008

Transient headache related to enlargement of the contralateral vertebral artery after vertebral artery occlusion.

Shigeyuki Sakamoto; Shinji Ohba; Masaaki Shibukawa; Yoshihiro Kiura; Takahito Okazaki; Kaoru Kurisu; Yosuke Kajihara; Kazutoshi Mukada

BACKGROUND Endovascular proximal parent artery occlusion has been performed for VA dissection. We describe a case that presented with headache associated with transient enlargement of contralateral VA after VA occlusion. CASE DESCRIPTION A 54-year-old man presented with constant occipital headache on the left due to left VA dissection. Proximal parent artery occlusion of the left VA with detachable coils was performed, and the headache disappeared after coil occlusion. However, the patient presented with occipital headache on the right 1 week later. The MRI showed enlargement of the right VA compared with before the procedure. Four weeks later, the right occipital headache disappeared, and MRI showed improvement of enlargement of the right VA. CONCLUSION The patient might present with right occipital headache related to transient enlargement of contralateral VA after VA occlusion. Careful postoperative neuroradiological examination of the contralateral VA is required because contralateral VA enlargement may be caused by hemodynamic stress after VA occlusion.

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