Masahiro Yonekura

Nagasaki Medical Center

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Hiroshi Baba

Niigata University Medical and Dental Hospital

Keisuke Toda

National Epilepsy Center

Hideaki Takahata

Nagasaki University Hospital

Keisuke Tsutsumi

Nagasaki Medical Center

Tomonori Ono

Nagasaki Medical Center

Ichiro Kawahara

Nagasaki Medical Center

John B. Craft

American Cancer Society

Yoichi Morofuji

Nagasaki University

Shigeyoshi Teramoto

Nagasaki Medical Center

Tadayoshi Moriyama

Sasebo City General Hospital

Cooperative Institutions

Nagasaki University

Nagasaki Medical Center

University of Southern California

Nagasaki University Hospital

The University of Tokyo

Kyoto University

University of California, Los Angeles

University of California, San Francisco

Los Angeles Medical Center

George Washington University

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The Results of Intensive Delayed Operation on Ruptured Cerebral Aneurysm

Surgery for Cerebral Stroke (1995)

Masahiro Yonekura Shigeyoshi Teramoto Hiroshi Baba Tamotsu Toba Ryujiro Ushijima

A series of 269 patients with ruptured cerebral aneurysm over the last five years were analyzed. This series consists of 227 patients whose operations were delayed for about 2 weeks, 17 patients with intracerebral hematoma in acute operation and 25 patients without treatment because of severe grade clinically (Hunt & Kosnik Grade V ). In the group whose operations were delayed 2 weeks, the rate of ADL 1 and 2 is 93.3% in Hunt & Kosnik Grade I, 77.7% in Grade II, 67.2% in Grade III and 52.6% in Grade IV. And also the rate of ADL 1 and 2 is 94.4% in Fisher Group 1 on CT scan, 84.2% in Group 2, 68.5% in Group 3 and 72% in Group 4. The factors of poor prognosis in ADL 3, 4 and 5 are 8.8% in the rerupture, 8.4% in the vasospasm, 6.2% in the complication and 1.8% in the operation technique. In all patients with ruptured cerebral aneurysm, the rate of 1 and 2 is 65.4% of 269 patients. The factors of poor prognosis in ADL 3, 4 and 5 and 12% in the initial attack, 7% in the rebleeding, 6% in the vasospasm, 6% in the complication and 2% in the operation technique.

Cerebral Vasospasm

10.2335/scs1987.23.4_297

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2. Natural history of small unruptured intracranial aneurysm (M2-A Current issues on unruptured aneurysm)

Japanese Journal of Neurosurgery (2004)

Shin Nakajima Masahiro Yonekura

10.7887/jcns.13.322_2

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[Primary intracranial germ cell tumor in the right basal ganglia and its vicinity area--a report of the case with germinoma and choriocarcinoma histologically].

PubMed (1983)

Tadayoshi Moriyama S Teramoto Hiroyuki Kitajima Masahiro Yonekura Masaru Nakamura

A case of intracranial germ cell tumor in the right basal ganglia and it's vicinity area was presented and previous reported cases were reviewed. The patient was a 11-year-old boy with precocious puberty. His illness started with left hemiparesis and mental disturbance, i.e. behavioral and emotional change one year prior to admission. Enhanced CT demonstrated a round lesion of high density, with relatively low density in the center portion. The tumor developed from the right putamen to thalamus, and involved toward hypothalamic region on coronary CT. Hormonal studies revealed abnormal levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), human chronic gonadotropin (HCG), and testosterone. In addition to excessively high levels of HCG in the urine, serum and CSF, high elevation of plasma LH and low of plasma FSH were revealed. On 3 June 1980, right temporal craniotomy was performed and a piece of the tumor was removed. Tumor's tissue was diagnosed as germinoma by pathohistological examination. As the effect of postoperative Co-60 radiation, high density area on CT disappeared and remained as well margined low density area. On repeated CTs and HCG-measurements on further, recurrent sign was not noted up to now. However, as a result of pathohistological studies in details, syncytiotrophoblast generally seen in the choriocarcinoma seem to be presented in it's tissue. Therefore, by means of peroxidase labeled antibody method, the authors proved HCG in syncytial cells of the tumor's tissue. There are very little reports on quantification of HCG in primary intracranial germ cell tumor with precocious puberty. Serial measurements of HCG are useful for following the diagnosis and therapy of primary intracranial germ cell tumors. In this report, the authors provide evidence that the syncytial cell mixed in intracranial germinoma secrets HCG.

Germinoma

Gonadotropin

Brain tumor

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INTRAVENOUS INJECTION OF BUPIVACAINE IN THE PREGNANT EWE

Anesthesiology (1979)

John B. Craft E. G. Co Masahiro Yonekura Michael F. Roizen Paul Mazel

10.1097/00000542-197909001-00309

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Gamma Knife Surgery for the Treatment of Spontaneous Dural Carotid-Cavernous Fistulas

Neurologia medico-chirurgica (2003)

Masanari Onizuka Katsuharu Mori Nobuaki Takahashi Ichiro Kawahara Takeshi Hiu

Endovascular treatment for a spontaneous dural carotid-cavernous fistula (CCF) is an established treatment, but stereotactic radiosurgery might provide a less-invasive alternative in selected cases. Four women aged 67 to 79 years (mean 72.0 years) with spontaneous dural CCFs presented with chemosis or bruit. Angiography revealed arteriovenous fistulas in the cavernous portion. Three cases were Barrow type D and one was type B converted from type D. Stereotactic gamma knife surgery was performed with a marginal dose of 13-15 Gy and a maximum dose of 26-30 Gy with a volume from 824 to 1755 mm3. The target point of radiosurgery for type D CCFs was the compartment of the cavernous sinus supplied by multiple feeders from the external carotid artery. All patients responded favorably to the treatment, with improvement of symptoms beginning after 1 to 3 months. Angiography confirmed the complete disappearance of the CCFs in all patients. There were no recurrences, and the follow-up period was 14 to 32 months (mean 24 months). No significant side effects were observed. Stereotactic radiosurgery is a useful method to treat CCFs and is indicated for elderly patients, low-flow CCFs, and cases in which endovascular treatment has failed.

Chemosis

10.2176/nmc.43.477

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Citations (33)

The Natural History of Unruptured Intracranial Aneurysms Based on the Analysis of SUAVe Study and Other Published Data(<SPECIAL ISSUE>New Concept in Treatment for Cerebral Aneurysm)

Japanese Journal of Neurosurgery (2012)

Tomosato Yamazaki Makoto Sonobe Masahiro Yonekura Haruhiko Kikuchi

Small Unruptured Intracranial Aneurysm Verification Study (SUAVe Study, Japan)は小型未破裂脳動脈瘤の自然歴に関する研究であり,径5mm未満の未破裂脳動脈瘤の破裂率,増大率とそれぞれにかかわる危険因子を前方視的に検討した.2000年9月〜2004年1月までの3年4ヵ月間に540動脈瘤(446症例)が登録され,448動脈瘤(374症例)が平均42.5ヵ月間(1,306.2人・年,1,553.5動脈瘤・年)のfollow-up期間で経過観察された.観察期間中7症例(1.9%)にくも膜下出血を生じ,年間の破裂率は0.54%(単発症例0.34%,多発症例0.95%)であった.破裂にかかわる危険因子は年齢50歳未満,動脈瘤径4.0mm以上,高血圧,多発瘤であった.25症例(6.7%)に動脈瘤の増大を認め,その危険因子は動脈瘤径4.0mm以上,女性,多発瘤,喫煙であった.小型未破裂脳動脈瘤の破裂率は非常に低く,安定した動脈瘤と考えられる.しかし,上記リスクを抱える症例は,将来的に動脈瘤の破裂や増大にかかわる可能性を秘めており,注意深い観察や破裂予防処置を考慮する必要がある.

10.7887/jcns.21.288

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De novo ruptured aneurysm at the site of anastomosis after superficial temporal artery–middle cerebral artery anastomosis—Case report and literature review

Clinical Neurology and Neurosurgery (2012)

Ichiro Kawahara Yoichi Morofuji Keisuke Tsutsumi Hideaki Takahata Tomonori Ono

Superficial temporal artery

Clipping (morphology)

Pseudoaneurysm

Moyamoya Disease

10.1016/j.clineuro.2012.05.044

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Citations (8)

BOLUS INJECTION OP CHLOROPROCAINE IN THE PREGNANT EWE

Anesthesiology (1980)

John B. Craft S. D. Dao Masahiro Yonekura E. G. Co David P. MacKinnon

Bolus (digestion)

10.1097/00000542-198009001-00313

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Citations (1)

Moyamoya Vessels associated with Multiple Cerebral Aneurysms

Neurologia medico-chirurgica (1986)

Tadayoshi Moriyama Shigeyoshi Teramoto Haruo Kitajima Masahiro Yonekura Hideharu Fujii

A case of multiple cerebral aneurysms associated with so-called moyamoya disease is reported. The patient was a 52-year-old male attacked by subarachnoid hemorrhage. The patient was confused and signs of meningeal irritation were noted. Computed tomography (CT) scan showed the ventricular hemorrhage. Right carotid angiogram showed moyamoya vessels in the basal ganglia. The other angiograms showed three aneurysms, which were located at the origin of the posterior communicating artery (ICA-PCA) on the left, at the posterior cerebral-posterior communicating artery origin (PCA-PcomA) on the right, and the distal site of the posterior choroidal artery (PchA) on the left. Two aneurysms located at the origin of PCA and ICA were clipped by the transsylvian approach, the former being reached through the moyamoya vessels. Spontaneous regression of an aneurysm at the peripheral portion of PchA were angiographically documented 10 days after the second operation. There were no changes around the basal ganglia on post-operative CT. Histological examination of a part of the flat and small middle cerebral artery (M1) gained during operation revealed proliferation of intima, elongated elastica interna and loss of media. Forty-four reported cases of so-called moyamoya disease with aneurysm were discussed. As for operative indication of the aneurysm associated with moyamoya vessels, the authors consider that the aneurysm classified after Okamoto, et al. as Type III or major artery aneurysm, was almost saccular and the operative approach does not always injure moyamoya vessels.

Moyamoya Disease

Posterior cerebral artery

Posterior communicating artery

Basal (medicine)

10.2176/nmc.26.160

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Citations (4)

Human immunodeficiency virus-1 seroprevalance among parturients in Los Angeles County Public Hospitals

International Journal of Gynecology & Obstetrics (1993)

Deirdre A. Hill J. Stopka Thomas LM Frenkel Robert H. Settlage M Lee

Seroprevalence

Medical record

10.1016/0020-7292(93)90801-3

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