内耳奇形による髄液耳漏の1例

Cerebrospinal Fluid Leak Due to Inner Ear Malformations

Ⅰ．は じ め に

　錐体骨由来の髄液漏は，一般的には外傷後，術後，炎症性疾患，腫瘍性疾患などに伴って生じる¹⁴⁾．これらの他に稀な原因として，内耳の先天異常により髄液漏を生じることがある^1-6,9,11-18)．

　内耳奇形の頻度は先天性難聴の約20％を占めるといわれているが³⁾，その中でも髄液漏が生じるのは非常に稀であり，脳神経外科領域で遭遇することは少ない．

　今回われわれは，髄膜炎を繰り返した内耳奇形による髄液漏の1例を経験し，外科的治癒が得られたので若干の文献的考察を加え報告する．

　A case of inner ear anomalies associated with recurrent meningitis found in a 66-year-old female is reported.

　The patient had had 2 episodes of meningitis in the previous one year period. Multidetector-row CT of the temporal bone and three-demensional fast imaging employing steady-state acquisition MRI revealed dysplasia of the bony labyrinth and enlarged fundus of the internal auditory canal (IAC). During surgical treatment,we confirmed the cerebrospinal fluid (CSF) leakage through a bony defect in the stapedial footplate. The inner ear was obliterated and contained small pieces of temporal fascia.

　A meningitis or CSF leakage due to innar ear malformation is extreamly rear condition for neurosurgeon. Though we always have to take it into condideration as a cause of CSF leakage.