二期的手術が有効であった蝶形骨縁巨大髄膜腫の1例

A Case of Large Sphenoid Ridge Meningioma Treated by 2-staged Surgery

Ⅰ．はじめに

　巨大な頭蓋底髄膜腫の手術は容易ではない．脳の主要血管や脳神経を巻き込み，内頸動脈系から腫瘍栄養血管が入り込んでいることも多い．腫瘍摘出に要する手術時間の延長や多量出血のため，一期的全摘出術はときに困難である．今回われわれは，蝶形骨縁巨大異型髄膜腫に対し放射線療法を含めた二期的手術を行って，易出血性の腫瘍が全摘出できた1例を経験したので，文献的考察を加え報告する．

　Large skull base meningiomas frequently encase the major cerebral vessels and cranial nerves, and receive blood supply from the branches of the internal carotid artery. One-stage resection of these tumors is difficult due to the long time needed for surgery and profuse bleeding from the tumor. We report herein a case of large sphenoid ridge atypical meningioma that was successfully resected using a combination of two-stage surgery and irradiation. A 56-year-old man was referred to us with mild left hemiparesis and visual deterioration. Computed tomography and magnetic resonance imaging showed a large sphenoid ridge meningioma. Angiography showed blood supply from the branches of both external and internal carotid arteries, and pial blood supply from the middle cerebral artery. In the first surgery after embolization of feeder vessels from the external carotid artery, the tumor was still hemorrhagic and was partially resected with 2,374ml of blood loss. Symptoms were improved after the first surgery. Pathological diagnosis was atypical meningioma. In the second surgery after 40Gy of irradiation, the remnant tumor was no longer hemorrhagic and was totally resected. Staged surgery with irradiation is one treatment option for large vascular skull base meningiomas, particularly for atypical meningiomas.