Motoharu Yokoyama
Niigata University
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Featured researches published by Motoharu Yokoyama.
Surgical Neurology | 1983
Tadashi Tsuchida; Ryuichi Tanaka; Motoharu Yokoyama; Hiroshi Sato
The case of a 55-year-old man with a nonfunctioning pituitary adenoma associated with an anterior communicating artery aneurysm that ruptured during transsphenoidal surgery is presented. This small aneurysm was not detected on bilateral angiography of the carotid artery before surgery. Computed tomography (CT) scans showed the pituitary adenoma extending to the suprasellar region and the sphenoid sinus. After intracapsular removal of the tumor, cerebrospinal fluid from an intraspinal catheter became bloody and CT scans disclosed massive subarachnoid hemorrhage. Repeated angiography revealed a tiny anterior communicating artery aneurysm, which was clipped on the 37th day after the operation. Risk factors in the procedure of transsphenoidal surgery, especially of a pituitary adenoma with suprasellar extension, are discussed.
Surgical Neurology | 1987
Mizuo Kuroki; Ryuichi Tanaka; Motoharu Yokoyama; Yoshikatsu Shimbo; Fusahiro Ikuta
The authors present an unusual case of a pituitary adenoma that developed into intracranial and intraspinal dissemination following intracranial surgery with adjunctive radiation, and review metastasis of pituitary adenomas in the central nervous system briefly in light of other reported cases.
Acta Neuropathologica | 1993
Hiroshi Suzuki; Kiyomitsu Oyanagi; Hitoshi Takahashi; Mitsuo Kono; Motoharu Yokoyama; Fusahiro Ikuta
SummaryA pathological study was conducted on an autopsied patient who had undergone amputation of the right arm at the level of the shoulder 38 years prior to death. The numbers of anterior horn cells, spinal ganglion cells and myelinated fibers in the anterior and posterior spinal roots at the cervical segments were examined quantitatively and compared with those of age-matched control subjects. On the amputation side, anterior horn cells, spinal ganglion cells and large myelinated fibers of the anterior and posterior roots were decreased in number. In addition, on the spared side, the medium-sized neurons of Rexeds lamina IX were shrunken, or decreased in number, and the number of small- and medium-sized myelinated fibers in the anterior roots was decreased. These findings indicate that the long-term effects of axonal amputation induce retrograde degeneration of the anterior horn and spinal ganglion cells on the amputation side, resulting in atrophy and a decrease of medium-sized neurons in the anterior horn even on the contralateral, spared side.
Neurologia Medico-chirurgica | 1984
Motoharu Yokoyama; Isamu Kurita; Mitsunari Yamashita; Goro Uemura; Yasuji Yoshida; Satoshi Abe
European Journal of Endocrinology | 1985
Kyuzi Kamoi; Terunori Mitsuma; Hiroshi Sato; Motoharu Yokoyama; Kazuo Washiyama; Rhuichi Tanaka; Okuhiro Arai; Nobuyuki Takasu; Takashi Yamada
Neurologia Medico-chirurgica | 1984
Hiroaki Hondo; Ryuichi Tanaka; Motoharu Yokoyama; Hiroshi Sato
Neurologia Medico-chirurgica | 1983
Nobuhisa Yamada; Motoharu Yokoyama; Kentaro Sekiguchi; Hiroshi Satoh; Ryoji Ishii; Ryuichi Tanaka; S. Nakashima
Neurologia Medico-chirurgica | 1982
Tadashi Tsuchida; Mitsunori Fukuda; Ryuichi Tanaka; Motoharu Yokoyama; Isamu Kurita; Goro Uemura; Haruko Naito
新潟医学会雑誌 | 1987
長行 谷; 哲也 高沢; 至 山本; いづみ 梨本; 一雅 五十嵐; 紳 笠原; 宏 中村; 政彦 宇井; 希子 山田; 晶子 津田; 健 百都; 正毅 伊藤; 昭 柴田; 瑞雄 黒木; 元晴 横山; 宏 佐藤; 隆一 田中; 兼三 金子; Nagayuki Tani; Tetsuya Takasawa; Itaru Yamamoto; Izumi Nashimoto; Kazumasa Igarashi; Shin Kasahara; Masahiko Ui; Mareko Yamada; Akiko Tsuda; Takeshi Momotsu; Seiki Ito; Akira Shibata
新潟医学会雑誌 | 1987
元晴 横山; 隆一 田中; 宏 佐藤; 瑞雄 黒木; 哲郎 田村; 寿介 伊藤; Motoharu Yokoyama; Ryuichi Tanaka; Hiroshi Sato; Mizuo Kuroki; Tetsuro Tamura; Jusuke Ito