振子様眼振，感音性難聴を合併した白皮症症例

Oculocutaneous Albinism with Horizontal Pendular Nystagmus and Sensory Hearing Loss

I．緒言

　白皮症はメラノサイト（メラニン産生細胞）の先天異常による遺伝性疾患で，病型として①眼皮膚型，②眼型，③皮膚型の3型に分類^1,2）されている。本症のうち眼皮膚型，眼型では自発眼振を伴うことがあるとの報告^2,3）がなされている。今回われわれは振子様水平性眼振と両側感音性難聴を合併した眼皮膚型白皮症の1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 15-year-old female with oculocutaneous albi-nism was studied otoneurologically and reported with a review of the literature. Horizontal pendular nystagmus and sensory hearing loss were detected. Spontaneous horizontal nystagmus with symmetrically pendular direction was found, but it disappeared in the dark or when the eyes were closed. And under Frenzel's spectacles, horizontal nystagmus alternans was appeared. This suggested that the nystagmus was caused not only by the disorders of fixational reflex, but also by the cerebellar disorders. Hearing loss was profound in the right side and moderate in the left side. In this case, hearing loss was inner ear type and it suggests that this was caused by the disorders of the stria vascularis, probably due to dysfunction of the melanocyte.