錐体ジストロフィを合併した眼底白点症の1例

Fundus albipunctatus in a case of cone dystrophy

　特異な眼底異常が55歳男性に偶然発見された。幼少時から夜盲を自覚していた。黄斑部に斑状の脱色素斑があり，血管アーケードから周辺の眼底全域に白点が散在していた。電気生理学的ならびに暗順応所見から，眼底白点症を伴う錐体ジストロフィと診断した。フルオレセイン螢光眼底造影はびまん性に網膜色素上皮障害を示唆する不規則な点状過螢光と，黄斑萎縮巣に一致した過螢光がみられた。インドシアニングリーン螢光造影では黄斑萎縮部の縁に過螢光，および血管アーケード耳側に網膜色素上皮の過形成と思われる点状の低螢光点があった。本邦での文献例の検索から，眼底白点症を伴う錐体ジストロフィは12例中11例が男性であった。

A 55-year-old male was referred to us for fundus disorders detected by chance. Night blindness had been present since childhood. Patchy depigmentation was present in the macula. Discrete white dots were distributed over the whole fundus outside the vascular arcade. Electrophysiological and dark adaptation studies led to the diagnosis of cone dystrophy associated with fundus albipunctatus. Fluorescein angiography showed diffuse irregular and spotty hyperfluorescence (suggesting disturbance in the retinal pigment epithelium), and showed hyperfluorescence indicative of atrophy in the macula.Indocyanine green angiography showed hyper-fluorescence along the margin of the atrophic macula. It also showed hypofluorescent spots along the temporal arcades suggesting hypertrophy of the retinal pigment epithelium. Out of 12 reported cases of cone dystrophy with fundus albipunctatus in Japan, 1 lcases happened to be male.