前庭神経炎—診断の要点と風疹ウイルス感染との関連性について

Etiological, Symptomatological and Serological Study on Vestibular Neuronitis

I．はじめに

　前庭神経炎は1952年Dix ＆ Hallpike^1）によって提唱された疾患概念で，近年その診断基準も作成され，めまい疾患のなかでは比較的よく知られている。しかし日常診療でその診断は必ずしも容易ではない。本疾患の自験例の臨床的観察から診断の要点を報告し，血清ウイルス学的検討からとくに風疹ウイルスとの関連について考察した。

Etiological, symptomatological and serological studies on vestibular neuronitis were carried out in 55 cases in Kitasato University Hospital from 1971 to 1987.

The following results were obtained;

1. The incidence of the disease was about 1 per cent of all cases with both peripheral and central vestibular disorders. The ratio of male to female was 1 : 1.7 and the onset of the disease was age 21 to 72 with a mean age of 44.2. Number of the cases with sudden onset of vertigo or dizziness started in the early half of each year were ob-served rather than in the later half of the year, and the occurrence rate of the disease was spo-radically high in 1982, 1985 and 1987.

3. The vestibular lesion was unilateral in 51 cases or 93 per cent and bilateral in 4 or 7 per cent.

4. Sixty per cent of the patients complained of vertigo and the remainder of a floating sensa-tion and an unsteady gait. Sixty seven per cent of the patients sensed apparent movement of a still target when they turned their head towards the ear of lesion side either actively or passively, but had clear vision during their head movement to the intact ear. This phenomenon was described by Tokumasu as "an unilateral jumbling phe-nomenon", which may disappear after relatively long-term habituation or elimination of sponta-neous nystagmus.

5. The paired serum test of rubella virus (HI) was carried out in 12 cases. A significant varia-tion of 4 times in the titer was seen in 2 cases. A very rare case with acute bilateral vestibular neuronitis in manifest rubella infection was also reported.