The Development of Flash Visual Evoked Potential Techniques for the Diagnosis of Visual Disorders with Dense Opacities of the Optic Media

Abstract

Visual evoked potentials (VEP)were recorded in a large normal
population. Significant age differences were found, and the P2 component (latency 116 m.sec.) was the most consistent component of the VEP both between and within the individuals.

The validity of the normal VEP criteria were tested in two groups
of patients with known visual field defects. One group with central lesions and hemianopia, and a second with senile macula
degeneration. The VEP varied with the degree of visual impairment
with low amplitudes, long latencies and no localization at either
occiput being consistent with poor acuity. The P2 component
appeared to be particularly effected by the loss of central retinal function.

Two prospective studies were carried out on patients with dense
opacities of the optic media. One group of patients had unilateral
longstanding cataracts, the second group had recently sustained
severe eye injuries with penetration of the globe. The VEP
was graded to predict a good visual recovery or no useful function
remaining and the gradings were significantly correlated with
the final visual outcome.

It was concluded that the flash VEP is particularly useful to
monitor visual function with dense opacities of the optic media
if there is damage to the central retina or visual pathways and
cortex.

Date of Award	Dec 1978
Original language	English
Awarding Institution	Aston University