Pattern visual evoked potentials and spatial vision in retrobulbar neuritis and multiple sclerosis.

In an attempt to resolve some of the reported disagreements between visual evoked potential (VEP) recordings and Snellen visual acuity in patients with multiple sclerosis, we compared these test results with sine-wave grating-contrast sensitivity curves. Disease that depressed visual sensitivity for high spatial frequencies, sparing low spatial frequencies, was associated with depressed visual acuity and attenuated small-check VEPs in the affected eye, while large-check VEPs were not attenuated. When visual sensitivity to all spatial frequencies was depressed, both large-check and small-check VEPs were attenuated, and Snellen acuity was reduced. In general, abnormalities in the contrast sensitivity curve predicted abnormalities in VEP amplitude, but VEP delay was less accurately predicted.