LOCAL ELECTRORETINOGRAM IN MACULAR DEGENERATION

An effective clinical method, using local electroretinograms, for detecting macular impairment is described. The method utilizes computer averaging of electroretinograms from a rapidly flickering four-degree redtest stimulus and an adaptation field whose luminance is above rod saturation. The ratios of the ERG amplitudes produced by stimulation of the macula to those obtained from stimulation of the optic disc are calculated. The method was tested on 14 normal eyes, on 14 eyes with senile macular degeneration and on six eyes with other ocular diseases. The technique differentiated patients with macular degeneration when the visual acuity dropped to the 20/40 to 20/80 range. © 1969.