Psychophysical dark adaptation studies were performed in six patients
with Best vitelliform macular dystrophy (BVMD) using a Goldmann-Weeker
s dark adaptometer. Prebleach thresholds were determined before obtain
ing a postbleach full recovery curve. Unlike patients with Stargardt m
acular dystrophy, all patients with BVMD showed a normal time to reach
their baseline dark adapted thresholds after bleaching of their rod v
isual pigment when tested in clinically normal appearing retina. Altho
ugh a lipofuscin material accumulates within retinal pigment epithelia
l cells in patients with either Best or Stargardt dystrophy, functiona
l findings pertaining to recovery of rod dark adaptation thresholds as
well as electro-oculogram light peak to dark trough ratios are differ
ent in these two disorders.