Reizo Shirane
Boston Children's Hospital
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Featured researches published by Reizo Shirane.
Stroke | 1999
Yasuko Yoshida; Takashi Yoshimoto; Reizo Shirane; Yoshiharu Sakurai
BACKGROUND AND PURPOSE Revascularization surgery for moyamoya patients is believed to prevent cerebral ischemic attacks by improving cerebral blood flow. However, measures preventing the occurrence of hemorrhagic moyamoya in patients have not yet been established in the literature due to the low rate of hemorrhage onset as well as the originally limited numbers of patients with moyamoya disease, poor understanding of the clinical course of rebleeding, correct surgical management, and long-term outcome. We present here the results of an overall survey of patients with hemorrhagic moyamoya disease in a district of Miyagi Prefecture in Japan and examine their clinical course, efficacy of revascularization surgery, and long-term outcome. METHODS This study included 28 moyamoya patients with episodes of intracranial hemorrhage between 1976 and 1988. The mean follow-up period was 14.2 years. There were 4 males and 24 females, aged 7 to 69 years (mean 39.2 years). Cerebral angiography and CT scans were performed for all patients. Surgical treatment was performed in 19 patients (67. 9%), and 10 patients (35.7%) underwent revascularization surgery. We observed the clinical course of all 28 patients. We also studied the relationship between the efficacy of surgical treatment and long-term outcome. RESULTS Five of the 28 patients (17.9%) died of the initial intracranial hemorrhage, and 2 patients died of other causes. Rebleeding occurred in 6 of the remaining 21 patients (28. 6%). The interval to rebleeding ranged from 2 to 20 years (mean 7.3 years). Of these 6 patients, 4 died of rebleeding. Rebleeding was observed in 1 of 8 patients who underwent bypass surgery and in 5 of 13 patients who did not, which suggested that rebleeding was less likely to occur in patients who had undergone bypass surgery. However, there was no significant difference in rebleeding ratio or mortality between patients with and those without revascularization surgery (P>0.05). CONCLUSIONS In this study, we compiled the results of meticulous follow-up conducted over the past 10 years for patients with hemorrhagic moyamoya disease. Because hemorrhagic moyamoya disease is known for its high rate of mortality at the time of rebleeding and often causes rebleeding long after the initial episode (as much as 20 years later), implementation of long-term preventive measures for rebleeding is necessary. This suggests that a long-term prospective study of a large number of patients with hemorrhagic moyamoya disease is required to determine whether bypass surgery prevents rebleeding of hemorrhagic moyamoya disease.
Childs Nervous System | 1995
Masayuki Ezura; Takashi Yoshimoto; Satoru Fujiwara; Akira Takahashi; Reizo Shirane; Kazuo Mizoi
To clarify the differences between childhood-onset moyamoya disease and that with onset in adulthood, we studied the clinical course and angiographic findings of adult patients (over 20 years of age) with moyamoya disease of childhood onset (up to 15 years of age). The clinical course in 25 patients could be assessed. The follow-up period was 5–27 years. Neurological deficits were noted in 11/23 and mental disorders in 9/21. In all except one, the illness had started before the age of 7 years. Neither neurological nor mental condition changed during or after adolescence (15–20 years of age). Two patients died of intracranial hemorrhage. The disease progressed in angiographic stage until adolescence, but had stabilized or almost stabilized by the age of 20 years. This study indicates that moyamoya disease with onset in childhood carries high morbidity and mortality. The disease advances in angiographic stage between childhood and adolescence, but stabilizes or almost stabilizes between adolescence and adulthood.
Stroke | 1985
M Kameyama; Jiro Suzuki; Reizo Shirane; Akira Ogawa
A new model of bilateral hemispheric ischemia was created in the rat by occluding the common carotid arteries and the basilar artery; this resulted in consistent and severe impairment of the cerebral blood flow. The procedure for producing this model is described, and the results of EEG and autoradiography obtained by this model are compared to those obtained by the four-vessel occlusion model.
Stroke | 1991
S Satoh; Reizo Shirane; Takashi Yoshimoto
Ischemic cerebrovascular disease in children is relatively rare. To clarify the clinical features of ischemic stroke occurring in infants and children, we evaluated 54 cases of cerebral infarction, excluding cases of moyamoya disease, in patients less than 16 years old at 24 clinics in the Tohoku (northeast) district of Japan. We observed two incidence peaks, one in little children and the other in junior high school students. Infection and minor head trauma were more frequently seen prior to ischemic strokes than was heart disease. The middle cerebral artery region, including the basal ganglia, was most commonly affected (49 patients, 91%) on computed tomograms. Angiography was performed in 48 patients (89%) and showed various types of occlusive lesions, mostly affecting the middle cerebral artery. Hemiparesis was the most common form of disability following ischemic strokes (48 patients, 89%). Surgical treatment was carried out in seven patients (13%). The clinical course of these cases showed that the recovery of children after a stroke tends to be better than that of adults, but that permanent disabilities, such as hemiparesis or mental retardation, occur commonly. Further investigation of juvenile cerebrovascular disease is important to prevent ischemic strokes in children.
Journal of Neurosurgery | 2010
Toshiaki Hayashi; Reizo Shirane; Miki Fujimura; Teiji Tominaga
OBJECT Young patients with moyamoya disease frequently exhibit extensive cerebral infarction at the time of initial presentation, and even in the early postoperative period. To investigate clinical characteristics in the early postoperative period, the authors prospectively analyzed findings of MR imaging, MR angiography, and SPECT before and after surgery. The authors focused in particular on how postoperative neurological deterioration occurred. METHODS Between August 2005 and June 2009, 22 patients younger than 18 years of age with moyamoya disease were treated at Miyagi Childrens Hospital. The mean patient age (+/- SD) was 8.58 +/- 4.55 years (range 2-17 years). Superficial temporal artery-middle cerebral artery bypass and indirect bypass of encephalosynangiosis between the brain surface and the temporal muscle, galea, and dura mater were performed in 35 hemispheres. Magnetic resonance imaging and MR angiography were performed before surgery, at 7 days postoperatively, and 3-6 months after surgery. A (123)I-isopropyl iodoamphetamine SPECT scan was also obtained pre- and postoperatively. RESULTS During the postoperative period, neurological deterioration was observed after 15 operations (10 cases of motor paresis, 1 of aphasia, and 4 of sensory disturbance) in 13 patients. All symptoms had resolved by the time of discharge, except in 2 patients who suffered cerebral infarction. All patients exhibited disappearance (94.3%) or reduction (5.7%) of transient ischemic attacks (TIAs) during the follow-up period. Perioperative studies revealed 2 different types of radiological findings, focal uptake decrease on SPECT indicative of cerebral ischemia due to dynamic change in cerebral hemodynamics caused by bypass flow, the so-called watershed shift, and perioperative edematous lesions on MR imaging due to cerebral hyperperfusion. The frequent occurrence of preoperative TIAs was significantly associated with watershed shift, whereas preoperative MR imaging findings and preoperative SPECT findings were not. Age at operation was the only factor significantly associated with postoperative hyperperfusion. CONCLUSIONS In young patients, moyamoya disease exhibits rapid progression, resulting in poor clinical outcome. The risk of postoperative neurological deterioration in very young moyamoya patients with frequent TIAs should be noted. The findings in this study showed that direct bypass is not completely safe in patients with moyamoya disease because it causes dynamic change in postoperative cerebral hemodynamics.
Stroke | 2002
Shunji Mugikura; Shoki Takahashi; Shuichi Higano; Reizo Shirane; Yoshiharu Sakurai; Shogo Yamada
Background and Purpose— We encountered several patients with childhood onset of moyamoya disease in whom the ipsilateral anterior and posterior circulations were predominantly involved. This study investigated whether this is an angiographic characteristic of this disease. Methods— We evaluated steno-occlusive lesions on angiograms of 85 patients with pediatric onset of moyamoya disease, using two 4-stage angiographic classification scales for the internal carotid artery and posterior cerebral artery systems (ICA and PCA staging, respectively) and determined whether lesions with more advanced ICA and PCA stages were on ipsilateral sides. Results— When positive laterality was defined as the presence of a difference by ≥1 stage between the stages on both sides, lateralities in the ICA stages and in the PCA stages were present in 40 (47%) and 27 patients (32%), respectively. Lesions with more advanced ICA and PCA stages were on the same side, with significant probability (P =0.024, Fisher’s exact test). Lateralities in both ICA and PCA lesions were found in 17 patients. In 14 (82%) of the 17 patients, the more advanced side of ICA lesions was the same as that of PCA lesions, while it was contralateral in 3 patients (18%). Conclusions— In pediatric-onset moyamoya disease, asymmetrical involvement of bilateral ICAs and PCAs was common, and the ipsilateral ICA and PCA tended to be predominantly involved.
Clinical Neurology and Neurosurgery | 1997
Reizo Shirane; Yasuko Yoshida; Toshie Takahashi; Takashi Yoshimoto
In the surgical treatment of childhood Moyamoya disease, we have been performing a new non-anastomotic bypass surgery using encephalo-galeo-myo-synangiosis (EGMS) with dural pedicle insertion over the brain surface. To assess the results obtained using this procedure, the long-term clinical outcome and the characteristics of cerebral blood flow and oxygen metabolism using PET were evaluated. The subjects were 19 patients with childhood Moyamoya disease admitted to our institution over 8 years from 1988 to 1996. This type of surgery was performed 39 times and the patients have been followed up from 10 months to 8 years. Preoperatively, although cerebral blood flow and oxygen metabolism were varied from individual to individual, low values of regional cerebral blood flow (rCBF) and regional cerebral metabolic rate of oxygen (rCMRO2) with relatively high values of regional oxygen extraction fraction (rOEF) were found in the frontal region in most of the patients compared to normal children. Postoperatively, obvious improvement of cerebral blood flow and hemodynamics in all the areas in the operative site and clinical symptoms and signs ameliorated or disappeared during the follow-up period. In conclusion, the present method appeared to be useful to improve the hemodynamic in the brain and its long-term clinical outcome was satisfactory.
Neurosurgery | 2009
Toshiaki Hayashi; Reizo Shirane; Teiji Tominaga
OBJECTIVEIn patients with moyamoya disease, surgery to revascularize the ischemic brain is a recommended treatment. However, there are a few patients who require additional revascularization surgery because of progression of the disease. Even patients who show no postoperative ischemic symptoms at first may experience late deterioration. We performed additional surgery for such lesions using occipital artery (OA)–posterior cerebral artery (PCA) bypass with indirect revascularization. The efficacy of the procedure is reported. METHODSWe treated 3 patients with moyamoya disease who showed a transient ischemic attack after revascularization surgery. Three female patients, ranging in age from 6.0 to 35.2 years (mean age, 23.8 years) at the time of surgery, with ischemic symptoms (leg monoparesis in 2, visual impairment in 1) underwent the additional revascularization procedure. Preoperatively, all patients underwent indirect and/or direct revascularization surgery for initial treatment. All patients showed progression of the disease, especially in the PCA. OA–PCA bypass with encephalogaleodurosynangiosis and burr hole surgery were performed for postoperative ischemic symptoms. RESULTSAll patients showed clinical and radiological improvement. The transient ischemic attack was improved in all 3 patients. They did not complain of transient ischemic attack in the recent follow-up period. Follow-up magnetic resonance imaging showed no additional cerebral infarction. Magnetic resonance angiography showed widening of the OA and development of peripheral collateral vessels. Postoperative single-photon emission computed tomographic studies showed marked increase of uptake in both anterior cerebral artery and PCA territories. Cerebral vasodilatory capacity evaluated by an acetazolamide test also showed marked improvement. One patient showed postoperative cerebral edema as a result of focal cerebral hyperperfusion. CONCLUSIONOA–PCA anastomosis with indirect revascularization was effective for postoperative ischemia that showed symptoms in the anterior cerebral artery and PCA territories as a result of progression of a PCA lesion.
Journal of Neuro-oncology | 2003
Ryuta Saito; Toshihiro Kumabe; Hidefumi Jokura; Reizo Shirane; Takashi Yoshimoto
AbstractObject: Symptomatic spinal dissemination of malignant astrocytoma is rarely found except at autopsy. This study evaluated the clinical incidence and characteristics of spinal dissemination and the effect on outcome. Patients and methods: Patients treated for primary malignant astrocytoma, including 33 with anaplastic astrocytoma and 35 with glioblastoma, at our department between 1997 and 1999 were followed up until April 30, 2001. Head magnetic resonance (MR) imaging of all patients was obtained every 2–3 months. Signs and symptoms of leptomeningeal spread were checked at monthly outpatient examinations. Spinal MR imaging was performed if any symptoms indicating spinal dissemination were found. Results: Median survival times of patients with anaplastic astrocytoma and glioblastoma were 40.5 and 16.0 months, respectively. Seventeen patients (25%) developed intracranial dissemination and 15 of these died. Six patients (8.8%), one with anaplastic astrocytoma and five with glioblastoma, developed spinal dissemination. All patients with spinal dissemination also had intracranial dissemination. Five of the six patients died, despite systemic radiochemotherapy in four patients. All patients died of extensive whole brain and spinal dissemination or nodular mass enlargement at the upper cervical cord, not of local massive tumor progression. Conclusions: Symptomatic spinal dissemination of malignant astrocytoma is not so rare, and is the cause of death. The relatively high incidence of symptomatic leptomeningeal dissemination must be considered in the treatment of malignant astrocytomas.
Surgical Neurology | 1992
Akira Ogawa; Michiyasu Suzuki; Reizo Shirane; Takashi Yoshimoto
A patient with trigeminal neuralgia caused by a tortuous vertebrobasilar artery is reported. To obtain safe and certain neurovascular decompression of the trigeminal nerve, the tortuous vertebrobasilar artery was repositioned by pulling it toward the dura mater of the clivus using a synthetic vascular slip. The authors describe the technique of repositioning of the tortuous vertebrobasilar artery and its usefulness.