Electrophysiological analysis of Stargardt's disease fundus flavimaculatus group

Stargardt's disease-fundus flavimaculatus has four general distribution patterns in fundus appearance: (1) macular degeneration without flecks; (2) macular degeneration with perifoveal flecks; (3) macular degeneration with diffuse flecks; and (4) diffuse flecks without macular degeneration (Noble and Carr, 1979). Four cases corresponding each to the four subgroups were studied electrophysiologically by our new tests for the cone receptor cell (rapid off-response in the ERG) and for the retinal pigment epithelium (the hyperosmolarity response and the Diamox response). The results of our electrophysiological tests appear consistent with the histological findings by Klien and Krill (1967) and by Eagle et al. (1980), showing that the primary defect of fundus flavimaculatus is in the retinal pigment epithelium. Electrophysiologically, the severity of the disease correlated well with each fundus pattern.