内耳機能の保存されていた真珠腫内耳進展例

Cholesteatoma Invading into Inner Ear:Report of a Case

　はじめに

　一般に真珠腫の広範な内耳進展例では内耳（蝸牛および前庭半規管）機能が低下・廃絶していることがほとんどであるが，近年，それが保たれている例のあることが報告されるようになった^1,2）。

　私どもは最近，真珠腫が広範に内耳に進展していたが，術後も内耳機能の保たれた例を経験した。その症例をここに報告するとともに，内耳機能の防御機能につき，文献的考察と，若干の推論をつけ加えた。

A case of labyrinthine invasion which was caused by cholesteatoma and their hearing level had not changed even after the operation was reported.

A 41 year-old woman had a slowly pogressivehearing loss in her right ear, and suffered from vertigenous sensation. An attic perforation indicated cholesteatoma in the right ear. A x-ray examina-tion showed destruction of the lateral and posterior semicircular canals.

At the time of operation, cholesteatoma was found invading into the inner ear lateral to the membrana limitans and removed without rupture of the membrana limitans.

Hearing of the operated ear was preserved after the operation.