Dark adaptation in patients with Best vitelliform macular dystrophy.

Psychophysical dark adaptation studies were performed in six patients with Best vitelliform macular dystrophy (BVMD) using a Goldmann-Weekers dark adaptometer. Prebleach thresholds were determined before obtaining a postbleach full recovery curve. Unlike patients with Stargardt macular dystrophy, all patients with BVMD showed a normal time to reach their baseline dark adapted thresholds after bleaching of their rod visual pigment when tested in clinically normal appearing retina. Although a lipofuscin material accumulates within retinal pigment epithelial cells in patients with either Best or Stargardt dystrophy, functional findings pertaining to recovery of rod dark adaptation thresholds as well as electro-oculogram light peak to dark trough ratios are different in these two disorders.