Pattern dystrophy of the retinal pigment epithelium and geographic atrophy of the macula

Abstract

Purpose: Little information is available on the long-term course of pattern dystrophies, although some older individuals have been observed with macular atrophy. We sought to evaluate the evolution of symptoms, fundus changes, and physiologic findings by re-examining a family with pattern dystrophy after 20 years.

Methods: Four patients of seven initially examined were reevaluated 20 years later; two additional affected family members over age 60 were studied for the first time. Patients' current ages ranged from 38 to 73 years. Comprehensive ophthalmic examinations were supplemented with fluorescein angiography, dark adaptometry, color vision, electroretinography, and electrooculography.

Results: During the 20-year interval, visual acuity remained stable and 20/40 or better in all patients. One 62-year-old patient developed paracentral scotomas. All fundi showed evolution of pigmentary changes and increasing atrophy of pigment epithelium and choriocapillaris in the macula. Electro-oculograms were originally subnormal in all patients and changed very little. Electroretinograms, initially normal in two patients, became borderline or mildly subnormal and slightly reduced in the two patients first examined after age 60.

Conclusions: Pattern dystrophy in this family was associated with minimal diminution of visual function during a 20-year interval. However, there was electroretinographic evidence of mild diffuse photoreceptor damage in the older patients, and geographic macular atrophy was prominent (suggesting a risk of vision loss in old age). Some cases of atrophic, age-related macular degeneration may represent an evolution of pattern dystrophy.