Electrophysiological study on central retinal functions in retinitis pigmentosa
Murayama, K.; Adachi-Usami, E.
Nippon Ganka Gakkai Zasshi 92(11): 1844-1849
1988
ISSN/ISBN: 0029-0203 PMID: 3228032 Document Number: 314077
Pattern visually evoked cortical potentials (PVECPs) were recorded from 49 patients (94 eyes) of retinitis pigmentosa (RP) with good central visual functions. Measurable PVECPs were recorded from 60 eyes out of 94 eyes. In 28 RP eyes, temporal frequency characteristics were determined based on the P100 amplitude of VECPs. Decreased VECP amplitudes were observed at all temporal frequencies, but were more prominent at lower frequency ranges. In addition, we measured the luminance threshold in 8 patients (12 eyes) with RP using PVECPs. With decreasing pattern luminance (0 to 3.0 log unit neutral density filters), the amplitude of P100 component decreased linearly. Luminance threshold was determined by extrapolating the regression line of amplitude as a function of luminance to 0.mu.V. The results showed the luminance threshold was approximately 1.2 log units higher in RP than in age matched normal controls. Thus, the PVECP, may provide a way of quantitatively evaluating central retinal visual function in RP patients.