X-linked recessive cone dystrophy with tapetal-like sheen. A newly recognized entity with Mizuo-Nakamura phenomenon.

We encountered a new X-linked recessive cone dystrophy in which patients have a greenish-golden tapetal-like sheen of the retina; while the retinal sheen and electroretinographic abnormalities are present from childhood, patients are not symptomatic until adult years. All of the male patients tested showed evidence of cone dysfunction on color vision testing, dark adaptometry, and electroretinography. After three hours of dark adaptation, the tapetal-like sheen disappeared, with most areas changing from greenish-golden shades to orange-red hues (Mizuo-Nakamura phenomenon). One male patient had a retinal detachment from atrophic round holes in the equatorial retina.