副神経神経鞘腫の1例

A Case of Accessory Nerve Neurinoma Presenting an Intracisternal Tumor

I．はじめに

　神経鞘腫は感覚神経系に発生することが多く，運動神経系から発生することは稀である．明らかに副神経より発生した神経鞘腫はきわめて稀で，これまで13例が報告されているにすぎない．今回，大槽内に発育し，大後頭孔部腫瘍の臨床像を呈した副神経鞘腫の1例を経験したので若干の文献的考察を加え報告する．

A case of neurinoma from the spinal accessory nerve which is located in the cisterns magna is reported. A 54-year-old woman was admitted to the institute in 1990 with complaints of headache, nausea and ataxic gait for several months. Plain CT showed dilation of the lateral ventricles and a mass of lower density in the cisterna magna. The capsule and septa of the mass were enhanced with contrast medium. MRI showed the mass was low intense on T1-weighted images and high intense on T2-weighted images. Gadolinium visualized the mass multicystic. V-P shunt was performed before tumor resection. Through suboccipital craniectomy and C1 laminectomy the tumor was removed. The tumor had a long neck attached to the right spinal accessory nerve and extended to the cisterna magna.