Pattern electroretinograms recorded with a skin electrode in pigmentary retinal degeneration

Abstract

In 24 patients suffering from pigmentary retinal degeneration the electroretinograms to pattern stimulation (PERG) were recorded with a silver-cup electrode placed on the center of the lower eyelid skin referred to an electrode on the earlobe. The results were compared with the responses to flash stimulation (FERG) and pattern visual evoked cortical potentials. None of patients showed normal FERGs. Nineteen of 48 eyes showed subnormal FERGs. The PERG was recorded from those 19 eyes. In the remaining 29 eyes with flat FERG, 8 eyes showed clear PERGs. The peak latency of the first positive component of PERGs was found to be prolonged in these patients. PERGs seemed to be recordable in the patients whose visual acuity and central visual field were relatively well preserved.

Temporal frequency characteristics of retinitis pigmentosa obtained by pattern visual evoked cortical potential to checkerboard stimuli

“…Our previous studies [1][2][3] on patients with RP showed a good correlation between visual acuity, central visual field, and PVECPs in observations of [8], sensitivity drops at lower frequencies in curves obtained with homogeneous field stimuli [9,10], while no attenuation occurs with spatially structured stimuli. Using PVECPs to checkerboard stimuli, we found slightly low frequency attenuation in normal human subjects [11,12].…”

“…A more ideal procedure is the visual evoked cortical potential to pattern stimuli (PVECP) because it reveals central visual function without requiring bright light adapation. We have, therefore, been studying [1][2][3] the application of PVECP to patients with RP.…”