遅発性内リンパ水腫—症例報告と統計的観察

Delayed Endolymphatic Hydrops:Case Report and Statistical Observation

I．はじめに

　一側聾の既往をもつものにめまいが好発することは亀井ら^1）がすでに1971年に報告している。Nadolら^2），Wolfsonら^3）は1975年別個に，内リンパ水腫との関連でそれぞれ12例，5例の症例を報告した。Schuknecht　は1976年^4） delayed hydropssyndromeの概念を提唱し，さらに1978年^5）本疾患を難聴発症後年余を経て回転性めまいを反復するipsilateral typeと良聴耳の聴力変動をきたすcontralateral typeに分類した。今回著者らは遅発性内リンパ水腫自験例の14症例を報告し，Schu—knecht theoryの問題点について検討した。

Fourteen cases of delayed endolymphatic hydrops comprising ten patients with ipsilateral type and four con tralateral type were reported.

As the causes of profound hearing loss, mumps in five cases and bacterial infection in one case were found. However, the remaining eight cases had unknown etiology. In six of the patients, vertigo subsided spontaneously after repeated attacks for a certain period. We statistically analysed the causes of hearing loss, the interval between the discovery of hearing loss and the onset of paroxysmal vertigo, and caloric responses in comparison with those in the precedingly reported cases. Although Seim-knecht's theory sounds attractive to understand paroxysmal vertigo or fluctuating hearing loss in patients with severe hearing loss, it seemed difficult to explain all the cases of so-called delayed endo-lymphatic hydrops.