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Featured researches published by Kaita Yahara.


Neurosurgery | 2003

Primary intracerebral hemorrhage in Izumo City, Japan: incidence rates and outcome in relation to the site of hemorrhage.

Tetsuji Inagawa; Naohiko Ohbayashi; Akihiko Takechi; Masaaki Shibukawa; Kaita Yahara

OBJECTIVEThe aim of this community-based study was to investigate the incidence rates and outcome of primary intracerebral hemorrhage (ICH) in relation to the site of hemorrhage. METHODSThe subjects were 350 patients with primary first-ever ICH who were treated during the 8-year period 1991 to 1998 in Izumo City, Japan. RESULTSThe crude and age- and sex-adjusted incidence rates for all types of ICH were 52 and 47 per 100,000 population, respectively, for all ages. The most common site of ICH was the putamen (120 patients, 34%), followed by the thalamus (115, 33%), lobar areas (53, 15%), brainstem (30, 9%), cerebellum (25, 7%), and caudate nucleus (7, 2%). The crude and age- and sex-adjusted annual incidence rates per 100,000 population were 18 and 16 for putaminal, 17 and 15 for thalamic, 8 and 7 for lobar, 4 and 3 for cerebellar, 4 and 4 for brainstem, and 1 and 1 for caudate hemorrhages, respectively. The Glasgow Coma Scale scores on admission were best in patients with cerebellar hemorrhage and worst in those with brainstem hemorrhage. Surgery was performed for 34% of putaminal, 9% of thalamic, 14% of caudate, 21% of lobar, and 32% of cerebellar hemorrhages but not for brainstem hemorrhages. The 30-day case fatality rate was 11% for putaminal, 9% for thalamic, 14% for caudate, 11% for lobar, 0% for cerebellar, and 53% for brainstem hemorrhages. When patients with ICH were analyzed as a whole, the overall survival rates at 30 days, 3 months, and 3 years were 87, 83, and 73%, respectively. Both the short-term and long-term outcomes after ICH were directly related to the site of hemorrhage and the severity of bleeding, which was assessed by the hematoma volume and Glasgow Coma Scale score. Overall, 190 (54%) of 350 patients had a favorable outcome, and 55 (16%) had died at discharge. CONCLUSIONMarked differences were observed in the incidence rates and outcome of primary ICH in relation to the site of hemorrhage. The differences in outcome were primarily a result of differences in the severity of bleeding for each ICH subtype.


Neurologia Medico-chirurgica | 2014

Risk Factors Associated with Cerebral Vasospasm following Aneurysmal Subarachnoid Hemorrhage

Tetsuji Inagawa; Kaita Yahara; Naohiko Ohbayashi

We studied the risk factors associated with cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH). The subjects were 370 patients with ruptured aneurysms who fulfilled all of the following criteria: admission by day 2 after onset, operation performed by day 3 by the same surgeon (T.I.), Hunt-Hess grade I–IV, availability of bilateral carotid angiograms acquired by day 2 and repeated between days 7 and 9. The demographic, clinical, radiographic, surgical, laboratory, and electrocardiographic data were analyzed for angiographic vasospasm (AV), symptomatic vasospasm (SV), and cerebral infarction on computed tomography (CT) scan. Both CT-evident SAH and AV were graded as 0–IV. Among the 370 patients, AV grade III–IV, SV, and cerebral infarction occurred in 26%, 24%, and 20%, respectively. Univariate analysis showed that Hunt-Hess grade III–IV, SAH grade III–IV, intracerebral or/and intraventricular hemorrhage, rebleeding, cigarette smoking, hypertension, alcohol intake, leukocytosis, hyperglycemia, and electrocardiographic QTc prolongation, left ventricular hypertrophy (LVH), and ST depression were significantly related to at least one of AV grade III–IV, SV, or cerebral infarction. Multivariate analysis showed that SAH grade III–IV was the most important risk factor for vasospasm followed by LVH on electrocardiogram, cigarette smoking, and hypertension. AV grade III– IV, SV, and cerebral infarction occurred in 57%, 54%, and 39% of the 46 smokers with LVH, and in 43%, 49%, and 35% of the 68 patients who had both LVH and hypertension, respectively. CT-evident SAH, LVH, cigarette smoking, and hypertension are associated with vasospasm. In smokers or hypertensive patients, premorbid LVH appears to predict much more severe vasospasm.


Journal of Clinical Neuroscience | 2008

Giant cell tumor of the temporal bone with intratumoral hemorrhage.

Toshinori Matsushige; Mitsuo Nakaoka; Kaita Yahara; Kota Kagawa; Hiroshi Miura; Hideyuki Ohnuma; Kaoru Kurisu

We report a case of hemorrhagic giant cell tumor (GCT) of the temporal bone in a 77-year-old woman. The patient suffered from sudden-onset headache and vomiting associated with left temporal hemorrhage. MRI revealed a left temporal extradural mass lesion expanding to the subtemporal fossa, showing strong hypointensity on T(2)-weighted imaging. Subsequent MRI revealed tumor growth with multiple cystic components at 1-month follow up. The tumor was found to be a GCT associated with recent intratumoral hemorrhage and abundant hemosiderin pigmentation. T(2)-weighted MRI of the GCT strongly supported hemosiderin deposition. Secondary formation of cystic components in the GCT can also reflect prior hemorrhage and indicate the progression of shape modification. A literature review revealed that hemosiderin deposition in this rare entity is not as rare as previously thought and that massive intratumoral hemorrhage may occur.


Interventional Neuroradiology | 2016

Intraoperative cone-beam computed tomography contributes to avoiding hypoglossal nerve palsy during transvenous embolization for dural arteriovenous fistula of the anterior condylar confluence.

Akitake Okamura; Mitsuo Nakaoka; Naohiko Ohbayashi; Kaita Yahara; Shinya Nabika

Background Dural arteriovenous fistula of the anterior condylar confluence (ACC-DAVF) is a rare subtype of DAVFs that occurs around the hypoglossal canal. Transvenous embolization (TVE) with coils has been performed for most ACC-DAVFs with a high clinical cure rate. However, some reports call attention to hypoglossal nerve palsy associated with TVE due to coil mass compression of the hypoglossal nerve caused by coil deviation from the ACC to the anterior condylar vein (ACV). Herein, we report a case of ACC-DAVF in which an intraoperative cone-beam computed tomography (CT) contributed to avoiding hypoglossal nerve palsy. Case presentation A 74-year-old man presented with left pulse-synchronous tinnitus. An angiography detected left ACC-DAVF mainly supplied by the left ascending pharyngeal artery and mainly drained through the ACV. The two fistulous points were medial side of the ACC and the venous pouch just cranial of the ACC. We performed TVE detecting the fistulous points by contralateral external carotid angiography (ECAG). The diseased venous pouch and ACC were packed with seven coils but a slight remnant of the DAVF was recognized. Because a cone-beam CT revealed that the coil mass was localized in the lateral lower clivus osseous without deviation to the hypoglossal canal, we finished TVE to avoid hypoglossal nerve palsy. Postoperatively, no complication was observed. No recurrence of symptoms or imaging findings were detected during a five-month follow-up period. Conclusion An intraoperative cone-beam CT contributed to avoiding hypoglossal nerve palsy by estimating the relationship between the coil mass and the hypoglossal canal during TVE of ACC-DAVF.


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.


Interventional Neuroradiology | 2015

Intraoperative idiopathic subarachnoid hemorrhage during carotid artery stenting: A case report and literature review.

Akitake Okamura; Mitsuo Nakaoka; Naohiko Ohbayashi; Kaita Yahara; Shinya Nabika

Carotid artery stenting (CAS) has a fatal complication of intracranial hemorrhage (ICH) associated with cerebral hyperperfusion syndrome (CHS), i.e. brain hemorrhage and subarachnoid hemorrhage (SAH). Although SAH accounts for a small percentage of these patients, it is difficult to make a differential diagnosis of this syndrome from CHS without ICH because the clinical presentations resemble each other. Furthermore, not only does the cause of SAH following CAS remain unclear but also the role of controlling postoperative blood pressure is not detected in preventing ICH after CAS. Herein, we report a case of SAH following CAS and review previous literature to discuss the mechanism and the management of this fatal complication. A 78-year-old woman with a history of arteriosclerotic obliteration and myocardial infarction was referred to our department for intervention to asymptomatic severe stenosis of the right internal carotid artery. We performed CAS under local anesthesia. Although her blood pressure was controlled to normotension during the procedure, the patient complained of headache following predilation. Postoperative emergent non-contrast computed tomography revealed SAH with leakage of contrast medium occupying the right sylvian fissure. We continued strict blood pressure control, and the patient was discharged without any neurological deficit. A well-opened lumen of the stent was recognized three months later at the outpatient visit. Strict control of intraoperative and postoperative blood pressure may improve the outcome of SAH following CAS though the role in preventing ICH after CAS is unclear.


Radiology | 2005

Apparent diffusion coefficient of human brain tumors at MR imaging.

Fumiyuki Yamasaki; Kaoru Kurisu; Kenichi Satoh; Kazunori Arita; Kazuhiko Sugiyama; Megu Ohtaki; Junko Takaba; Tominaga A; Ryosuke Hanaya; Hiroyuki Yoshioka; Seiji Hama; Yoko Ito; Yoshinori Kajiwara; Kaita Yahara; Taiichi Saito; Muhamad A. Thohar


Journal of Neurosurgery | 2000

Primary intracerebral and aneurysmal subarachnoid hemorrhage in Izumo City, Japan. Part I: incidence and seasonal and diurnal variations.

Tetsuji Inagawa; Akihiko Takechi; Kaita Yahara; Jun Saito; Kouzo Moritake; Shotai Kobayashi; Yoshito Fujii; Chie Sugimura


Surgical Neurology | 2006

Tentorial dural arteriovenous malformation manifesting as trigeminal neuralgia treated by stereotactic radiosurgery: A case report.

Toshinori Matsushige; Mitsuo Nakaoka; Keiji Ohta; Kaita Yahara; Hisayo Okamoto; Kaoru Kurisu


Cancer Chemotherapy and Pharmacology | 2003

Staurosporine-induced apoptosis is independent of p16 and p21 and achieved via arrest at G2/M and at G1 in U251MG human glioma cell line

Fumiyuki Yamasaki; Seiji Hama; Hiroyuki Yoshioka; Yoshinori Kajiwara; Kaita Yahara; Kazuhiko Sugiyama; Yuji Heike; Kazunori Arita; Kaoru Kurisu

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