Rod and cone psychophysics and electroretinography: methods for comparison in retinal degenerations.

Methods have been developed to compare full field rod and cone electroretinograms with results of rod and cone static perimetric measurements across the visual field. In a limited number of patients with retinal degeneration, including two subtypes of retinitis pigmentosa, there were close relationships between electroretinographic and psychophysical parameters. Maximum b-wave amplitude and visual field area were highly correlated, as were electroretinographic and perimetric measures of sensitivity loss. Future application of the methods to large numbers of patients with typical retinitis pigmentosa may help elucidate different mechanisms of retinal degeneration.