Subfrontal Schwannomaの1例

Subfrontal Schwannoma: A case report

I．緒言

　頭蓋内に発生するneurinomaは，脳腫瘍全国集計調査報告では原発性脳腫瘍中8.9％（von Recklinghausen病を含む）を占め^12），その90％以上が第8脳神経に発生する．稀に，動眼神経^18），顔面神経^6,10），滑車神経^8），舌咽，迷走神経，副神経^7,21），舌下神経25）からの発生の報告もあるが，subfrontal schwannomaの報告は極めて稀である．今回われわれはCTスキャン像で，嗅窩部髄膜腫と鑑別を要し，その発生母地に関しても議論のあるsubfrontal schwannomaの1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 a 63-year-old woman with subfrontal schwannoma of the left side is presented. The patient had a two-month history of recent memory disturbance and unstable gait. Computed tomography represented an isodense mass lesion with large and small cystic components in the anterior cranial fossa, enhancing homogeneously after intravenous injection of contrast medium. Cerebral angiograms revealed a noticeable hypovascularity.

She underwent total resection of the tumor on May 21, 1986. It was verified that the tumor was attached to the left olfactory groove and had invaded the ethmoid bone.

It was suggested that this tumor arose from one of the meningeal branches of the trigeminal nerve or of the anterior ethmoid nerve.

Histological examination proved that this neoplasm was of schwannoma.