Hiroyasu Kamiyama

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BACKGROUND AND PURPOSE The importance of hemodynamic parameters for predicting outcome in patients with occlusive carotid disease remains controversial. The present study was aimed at testing the hypothesis that regional cerebrovascular reactivity (rCVR) to acetazolamide can be a reliable predictor of subsequent ischemic stroke in medically treated patients(More)
The contribution of erythropoietin- (EPO) receptors in target tissues, such as bone marrow and spleen, to the nonlinear pharmacokinetics of recombinant human EPO (rh-EPO) was evaluated in rats. The total body clearance after i.v. administration of rh-EPO (0.2-5 microg/kg) decreased as the dose of rh-EPO increased, approaching a plateau at high doses. The(More)
BACKGROUND AND PURPOSE Intracranial fusiform aneurysms can be divided into 2 clinically different subtypes: acute dissecting aneurysms and chronic fusiform or dolichoectatic aneurysms. Of these 2, the natural history and growth mechanism of chronic fusiform aneurysms remains unknown. METHODS A consecutive series of 16 patients with chronic fusiform(More)
In a series of 32 patients with internal carotid artery occlusion, regional cerebral blood flow (rCBF) and regional cerebral vasoreactivity (rCVR) were measured by xenon-133 single photon emission computed tomography and the acetazolamide test. We evaluated its usefulness in detecting the reduced cerebral perfusion reserve and predicting long-term(More)
A 47-year-old man presented with a rare case of dural cavernous hemangioma of the cerebellar falx incidentally detected as a mass lesion in the posterior cranial fossa. Neurological examination revealed no deficits or physical symptoms. Computed tomography demonstrated a well-demarcated hyperdense mass, with no calcification, in the cerebellar vallecula.(More)
BACKGROUND AND PURPOSE We reviewed surgically treated patients with pediatric moyamoya disease and examined whether vasoreconstructive surgeries reduced the risk of recurrent ischemic attacks and changed overall outcomes in terms of the patients' performance and intellectual status. METHODS Sixty-four hemispheric sides in 34 pediatric moyamoya disease(More)
BACKGROUND AND PURPOSE It is well recognized that revascularization surgery using direct and/or indirect bypass provides effective surgical management for pediatric moyamoya disease. However, surgical treatment of the adult hemorrhagic type remains controversial. In this study, the effect of surgery for adult moyamoya disease was investigated. METHODS We(More)
OBJECTIVE AND IMPORTANCE The beneficial effects of surgical revascularization on rebleeding in moyamoya disease remain unclear. This report is intended to clarify the effects of surgical revascularization on peripheral artery aneurysms, which represent one of the causes of intracranial bleeding in moyamoya disease. CLINICAL PRESENTATION Findings for three(More)
BACKGROUND Blood blister-like aneurysms (BBAs) are aneurysms with ill-defined fragile necks arising from an internal carotid artery (ICA) and associated with high mortality. OBJECTIVE To describe strategies and outcomes in patients in whom radial artery (RA) graft bypass with ICA sacrifice was considered as the primary treatment during the acute phase of(More)
OBJECT Although combined direct and indirect anastomosis in patients with moyamoya disease immediately increases cerebral blood flow, the surgical procedure is more complex. Data pertinent to the postoperative complications associated with combined bypass are relatively scarce compared with those associated with indirect bypass. This study investigated the(More)