OCT所見に左右差のみられた成人型卵黄様黄斑変性の1例

A case of adult-onset vitelliform foveomacular dystrophy with unsymmetrical findings by optical coherence tomograph

要約　目的：光干渉断層計（OCT）で左右眼に異なる所見を示した成人型卵黄様黄斑変性の症例の報告。症例：49歳女性が2年前からの両眼の変視症で受診した。変視症は左眼で顕著であった。所見：矯正視力は右1.2，左0.9で，網膜電図は正常であった。両眼黄斑部に1/4乳頭径大の卵黄様滲出斑があった。フルオレセイン蛍光眼底造影では，病変部は低蛍光で，その周囲に輪状の過蛍光があり，造影後期には病変部全体が淡い過蛍光を呈した。OCTでは，右眼では病変に一致する疣状の肥厚が視細胞内外節接合部と連続し，左眼ではこれが網膜色素上皮（RPE）と連続していた。結論：成人型卵黄様黄斑変性の49歳女性でのOCT所見として，一眼には視細胞内外節接合部に疣状の高反射，他眼にはRPEが疣状に肥厚する高反射があった。成人型卵黄様黄斑変性では，病変がRPEに限局するだけでなく，内層に波及する可能性がある。

Abstract.　Purpose：To report a case of adult-onset vitelliform foveomacular dystrophy with different findings between right and left fundus by optical coherence tomograph（OCT）. Case：A 49-year female presented with metamorphopsia since 2 years before. The left eye was claimed to be more severely affected. Findings：Corrected visual acuity was 1.2 right and 0.9 left. Electroretinography showed normal response to flash stimulus. A round lesion simulating yolk of one-fourth disc diameter was present in the macula in either eye. Fluorescein angiography showed hypofluorescence in the affected area surrounded by a hyperfluorescent ring. The finding was replaced by diffuse and modest hyperfluorescence in the after phase. OCT showed uneven hyperreflection at the junction of inner and outer hotoreceptors in the right eye. This hyperreflective line was continuous with the retinal pigment epithelium（RPE）in the left eye. Conclusion：OCT in a 49-year-old female with adult-onset foveomacular dystrophy showed irregularly intense reflection of inner and outer junction line of photoreceptors in the right eye, and enhanced reflection from the RPE in the left eye. There is a possibility that this clinical entity may induce lesions in the neuroepithelium as well as RPE.