中頭蓋窩に進展した顔面神経鞘腫の1例

Case Report of Facial Neurinoma: Its Signs and Symptoms

I．はじめに

　末梢性顔面神経麻痺の原因としては，特発性（ベル麻痺），ヘルペスウイルス（ハント症候群）などの他に，小脳橋角部腫瘍，後頭蓋窩腫瘍^1）などの頭蓋内腫瘍や内耳道内に発生する聴神経腫瘍，側頭骨内の髄膜腫^2）や顔面神経腫瘍，真珠腫などでも起こり，その鑑別が必要となる。すなわち腫瘍性病変か非腫瘍性病変かによって，その発症の仕方や症状に違いがあると思われる。今回顔面神経精腫の1例を経験したので，その概要を述べ，参考に供したい。

　A 39-year-old female developed slowly progressive and complete peripheral facial palsy of 13 years' duration, and long-lasting hyperkinesis for 8 years. She also presented a mixed hearing loss and no caloric response, vertigo and nystagmus in the left side. X-ray examinations showed destruction of the petrous bone and the upper roof of the internal auditory meatus. CT scan revealed a tumor shadow growing to the middle cranial fossa in the petrous bone. It was found during operation that the tumor originated from the geniculate ganglion of the facial nerve, and was diagnosed as facial neurinoma histologically. It should be remined that slowly progressive peripheral facial palsy lasting more than 6 months with hyperkinesis accompanied by a conductive or mixed hearing loss can be caused by a tumor in the temporal bone.