Steady-State Pattern Electroretinogram and Transient Visual Evoked Potentials Analysis in Glaucomatous and Healthy Eyes

Abstract

Purpose : The use of electrophysiology tests as a measure of retinal ganglion cell and visual pathway dysfunction has been established, however few studies have evaluated the potential clinical utility of two novel, office-based, rapid testing platforms of steady-state Pattern Electroretinogram (ss-PERG; Diopsys Inc., Pine Brook, NJ; Figure 1) and transient Visual Evoked Potential (t-VEP; Diopsys Inc., Pine Brook, NJ) in patients with glaucoma. The purpose of this study was to determine the ability ss-PERG and t-VEP to discern between glaucomatous and healthy eyes.

Methods : Patients with open-angle glaucoma (OAG) and healthy volunteers were enrolled in this prospective study. Parameters compared were MagnitudeD, MagnitudeD/Magnitude ratio, and signal-to-noise ratio (SNR) for ss-PERG and amplitude and latency for t-VEP. Mixed-effect model analyses were used to compare the ss-PERG and t-VEP parameters between OAG and healthy groups.

Results : A total of 41 patients (81 eyes) with OAG and 41 controls (82 eyes) with normal eye examination were enrolled. MagnitudeD was significantly lower in glaucoma patients when using a low contrast (P=0.001) and high contrast (P<0.001) 64-bar pattern ss-PERG stimulus. MagnitudeD/Magnitude and SNR were significantly lower in the glaucoma group when using a high contrast stimulus (P<0.001 and P=0.010 respectively). Receiver operated characteristic (ROC) curves had an area under the curve (AUC) of 0.68 for Magnitude D and 0.70 for MagnitudeD/Magnitude ratio when using a high contrast stimulus. t-VEP amplitude and latency were not significantly different in the two groups when using any stimuli.

Conclusions : Of the two electrophysiology tests, the ss-PERG was effectively able to discern between glaucomatous and healthy eyes. The most useful parameters for detecting glaucoma were Magnituted D and MagnitudeD/Magnitude ratio.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.

 

Figure 1. A. Electrode placement for steady-state Pattern Electroretinogram (ss-PERG) testing B. A 64-bar pattern ss-PERG stimulus C. ss-PERG results from a healthy control. D. ss-PERG results from a glaucoma patient with decreased amplitude and phase consistency.