Differential effects of optic media opacities on simultaneous multifocal pattern electroretinograms and visual evoked potentials

Abstract

Objective: To identify potential confounds in the comparison of simultaneously acquired multifocal electroretinograms (mfPERGs) and visual evoked potentials (mfVEPs) to pattern reversal stimulation.

Methods: With VERIS Science 5.1.10X monocular mfPERGs and mfVEPs were recorded simultaneously to optimised pattern-reversal stimulation for a reference condition and two filter conditions, i.e. blur and 8% luminance transmission, in two separate experiments in participants with normal vision. The impact of the filter conditions on mfPERG amplitude (P50 and N95 peaks), mfVEP-magnitude (root-mean-squares and signal-to-noise-ratios), and on the response timing was assessed.

Results: Blur reduced mfPERG P50 and N95 amplitudes to 16%, 21%, and mfVEP magnitude to 82%. Decreasing stimulus luminance to 8% reduced only the mfPERG (P50 to 72% and N95 to 74%), but delayed both mfPERG and mfVEP responses by 5.3 and 4.6ms, respectively.

Conclusions: Comparatively minor stimulus manipulations, mimicking optic media opacities, had a differential effect on mfPERGs and mfVEPs magnitudes.

Significance: Simultaneous mfPERG/mfVEP recordings are a promising approach to compare retinal and cortical function, but caution must be exerted in the interpretation of response differences due to incongruent response characteristics.

Keywords: Ganglion cells; Image degradation; Luminance dependence; Retina; Visual cortex; mfPERG; mfVEP.