片眼性網膜色素変性が疑われた症例の健眼の光干渉断層計所見

Optical coherence tomographic findings of the apparently healthy eye in a case of unilateral retinitis pigmentosa

要約　目的：片眼性網膜色素変性と診断された症例の健側眼に光干渉断層計検査を行い，異常がみられた報告。症例：50歳女性が左眼の夜盲で紹介受診した。裸眼視力は左右とも1.2で，右眼の眼底，視野，蛍光眼底造影所見，網膜電図は正常であった。左眼には網膜色素変性に特有な眼底所見，輪状暗点があり，網膜電図は消失または振幅の低下があり，片眼性網膜色素変性と診断した。右眼の光干渉断層計検査で，上耳側血管アーケードの周辺部にIS/OSラインの不連続があり，この部位に視細胞層の菲薄化があると判断した。結論：本症例の健側眼にみられた光干渉断層計所見は，網膜色素変性の初期変化である可能性がある。

Abstract.　Purpose：To report abnormal findings by optical coherence tomography（OCT）of the apparently unaffected eye in a case of unilateral retinitis pigmentosa. Case：A 50-year-old female was referred to us for night blindness in the left eye. Visual acuity was 1.2 in either eye without correction. The right eye showed normal findings by funduscopy, perimetry, fluorescein angiography and electroretinography（ERG）. The left eye showed typical fundus findings of retinitis pigmentosa and annular scotoma. ERG was either extinguished or reduced in amplitude. The findings led to the diagnosis of unilateral retinitis pigmentosa. OCT in the right eye showed discontinuous IS/OS line and thinning of the neuroepithelial layer peripheral to the superior temporal vascular arcade. Conclusion：OCT findings in the present case are interpreted as initial fundus lesions of retinitis pigmentosa.