腫瘍摘出により交通性水頭症が短期間に改善した前庭神経鞘腫の1例

A Case of Hydrocephalus Associated with Vestibular Schwannoma,Treated by Tumor Removal

Ⅰ．は じ め に

　前庭神経鞘腫（聴神経腫瘍）には時に水頭症が合併する．今回われわれは，正常圧水頭症にみられる典型的な3徴を呈した水頭症が腫瘍摘出後1カ月ですみやかに画像上，臨床上も改善した水頭症合併前庭神経鞘腫を経験したので報告する．

A 57-year-old male presented with gait disturbance,urinary incontinence,dementia resembling symptom of normal pressure hydrocephalus (NPH) and was admitted to our institusion. A computerized tomographic scan (CT) and magnetic resonance imaging (MRI) revealed hydrocephalus as well as a tumor in the right cerebellopontine angle. We diagnosed communicating-type hydrocephalus associated with the vestibular schwannoma and tumor removal was performed prior to ventriculo-peritoneal (V-P) shunt. After surgery,symptoms of the patient disappeared promptly and cerebrospinal fluid protein elevation was normalized. One month after surgery,CT and MRI revealed reduction of the ventricle size and V-P shunt became unnecessary.

　Hydrocephalus is occasionally complicated by vestibular schwannoma. The majority results from obstruction of the cerebrospinal fluid (CSF) pathway by large tumors. But,small tumors also cause communicating-type hydrocephalus. Although the selection of the treatment is controversial,tumor removal without a shunt is considered as a good strategy for management of hydrocephalus associated with vestibular schwannoma.