真珠腫術後一過性にみられた拍動性異常眼球運動

Pulsating Eye Movements Transiently Observed after Surgery For Cholesteatoma

I．はじめに

　一般に慢性中耳炎には種々の合併症の可能性があるが，とくに真珠腫性中耳炎ではその危険性が高い。このうちもっとも多い合併症は瘻孔症状であろう^1）。迷路瘻孔を伴う真珠腫性中耳炎では，術前，術後にめまいを訴えることも少なくない^2）。

　今回，著者は瘻孔を伴う真珠腫性中耳炎の術後に特異なめまいと異常眼球運動を呈した症例を経験した。これは自覚的には脈拍と同期した拍動性の横ゆれで，それに伴って拍動性の異常眼球運動がみられた。このようなめまい，眼球運動は文献的にも珍しく，ここにその症例の詳細を報告するとともに過去の報告を紹介してその発生機序に関する考察を加える。

　This paper reports an unusual case presenting pulsating nystagmus-like eye movements transiently observed after surgery for cholesteatoma. A 56-year old man complained of sudden vertigo while cleaning his left ear canal. A large labyrinthine fistula of the lateral semicircular canal was confirmed during surgery. Postoperatively, abnormal eye movements beating synchronously with pulse were observed, and at the same time, the patient noted swaying sensation which was also pulse-synchronous. The findings were extremely unusual, and in the past, there appeared only one report of this phenomenon. Pulsating eye movements observed in this case might be interpreted as a kind of fistula sign, and the mechanism producing this phenomenon was discussed.