Intraosseous Meningiomaの1手術例

A Case of Intraosseous Meningioma

I．はじめに

　硬膜外に発生する髄膜腫はextracalvarial meningiomaと呼ばれ，文献的には1904年にWinklerら^19）が最初に報告している．そのなかでも，頭蓋骨内に主座をおき髄膜とはほぼ無関係に存在する髄膜腫はintraosseousmeningiomaと呼称され，1932年のAlpers^1）らの記載以来，本邦ではわずか数例が報告されているのみである^{4-6,8,12,18）}．

　最近われわれはintraosseous meningiomaと考えられた症例を経験したので，若干の文献的考察を加えて報告する．

A case of intraosseous meningioma at the posterior fossa was reported. Intraosseous meningioma is very rate and only six cases have been reported in Japanese literature.

A 64 year-old woman complained of progressive headache and was admitted to Ichinomiya Neurosurgic-al Hospital. On admission, neurological examination did not reveal any abnormalities. However, plain skull X-p showed a hyperostotic lesion in the right posterior fos-sa. CT scan demonstrated homogeneously enhanced mass by contrast medium. MRI showed a mass lesion of the posterior fossa on T1 and T2 weighted images. The right vertebral angiogram showed an avascular area in the right posterior fossa and no tumor stain. The tumor, which was partially attached to the under-lying dura, was successfully removed surgically. The operative finding confirmed an intraosseous meningioma which had arisen from the right asterion. The post op-erative course was uneventful. Histological examination revealed fibroblastic meningioma.