聴原発作と考えられた1症例

A case of audiogenic seizure

　I．緒言

　純音，雑音などを聞くことにより異常行動をきたし，最終的にはてんかん様発作を生ずる聴原発作（audiogenic seizure）は，動物実験によって，その発生機序などが研究されているが，臨床的な立場，特に耳鼻科領域における報告はあまりみられないようである。今回，筆者らは純音聴力検査中に不快感を訴えたため，種々検索した結果，聴原発作と考えられた症例を経験したので，若干の文献的考察を加えて報告する。

　A 38-year-old male, visited our clinic, was complaining of bilateral tinnitus. During pure tone audiometry, he complained of discomfort in his head, and developed audiogenic seizure.

　The patient had a history of head injury at 19 years of age.

　Roentgenography and neurological examinations showed no pathological findings.

　The following conclusions were obtained: 1. When he was stimulated by a tone of 700 Hz, 100 dB, a myoclonus-like reaction was observed. 2. The seizure was observed only by the stimulation on the right ear. 3. Electroencephalogram recorded during seizure showed fast activity of 18-20 c/s and low voltage in all leads. 4. Antiepileptic drugs were effective in this case.