ID 133 – Flash ERG and VEP – Comparison of stimulation by LED and Xenon lamp

Abstract

Objective Electroretinography (ERG) examines the functional integrity of the retina. Visual evoked potentials (VEP) are electrical responses recorded from occipital cortex which provides information about central visual pathways. The purpose of this study is to compare ERG and VEP results elicited with two different types of flash stimulator. Methods Seven healthy volunteers without any known ocular or neurological diseases were took part in this study. The mean age of participants was 23 (4 female-3 male). ERG and VEP responses were recorded with two different stimulators, Xenon lamp (Flash) stimulator and Light emitting diodes (LED) photic stimulator. Results There was no significant difference in the mean P100 latencies and amplitudes of Flash VEP and LED VEP ( p = 0.213, p = 0.145 respectively). The mean latencies of a-wave and b-wave were longer for LED ERG than Flash ERG but it did not reach a statistical significance ( p = 0.195). Also the amplitude of b-wave (measured from the trough of the a-wave to the peak of the b-wave) had no significant difference between Flash ERG and LED ERG. Conclusions These results taken altogether suggest that we could produce similar VEP and ERG responses with Xenon lamp and LEDs. Key words Visual Evoked Potentials, Electroretinography, Light Emitting Diodes