網膜色素変性を伴ったFisher症候群の1例

Fisher syndrome in a case of retinitis pigmentosa

　59歳女性に，急性発症と思われる外眼筋麻痺，腱反射消失，細胞増加のない髄液の蛋白増加が認められた。3か月後には自然寛解し，Fisher症候群と診断された。網膜色素変性があり，血清に乳酸とピルビン酸の増加があるために，Kearns-Sayre症候群が当初疑われた。経過中に矯正視力の低下と調節過剰によると思われる近視化があった。Fisher症候群では輻輳が障害され，網膜色素変性で視野狭窄があるために，注視が困難となり，調節過剰が生じたと解釈された。Fisher症候群で感覚障害があることを示す1例である。

A 59-year-old woman presented with external ophthalmoplegia of recent onset, areflexia and increased protein withuot pleocytosis in the cerebrospinal fluid. Spontaneous recovery set in three months later. These features led to the diagnosis of Fisher syndrome. Kearns-Sayre syndrome had to be differentiat-ed because of the presence of retinitis pigmentosa and increased levels of serum lactate and pyruvate. Her corrected visual acuities transiently deteriorated during the clinical course. A transient shift towards myopia occurred also, probably due to hyperaccommodation. Impaired convergence in Fisher syndrome in addition to visual field constriction due to retinitis pigmentosa seemed to have necessitated an excessive effort in fixation leading to hyperaccommodation.