Characteristics of Electroretinographic Off-response in Monkeys with Experimental Glaucoma

Abstract

Purpose: : Use flash electroretinogram (ERG) to investigate the function of Off-response in monkeys with high intraocular pressure (IOP).

Methods: : High IOP was induced by laser coagulation of the midtrabecular meshwork in the right eye (OD) of five monkeys. Long duration of ERG response was elicited by red flash with blue background. Stimulus luminance of red flash was 125 cd·m^-2 and stimulus duration was 200 ms. Ocular fundus photos were taken with a Non-mydiatic retinal camera.

Results: : Enlarged cup to disc ratio were found in the lasered eye of all five monkeys. Mean IOP in OD was over 2 times higher than that in left eye (OS). Two major components named d1-wave and d2-wave were noted after the stimulation of 200ms. Mean amplitude of d1-wave and d2-wave in OD was significantly lower than that in OS (P<0.05). No statistical difference was found in implicit time of d1-wave and d2-wave between the two eyes (P>0.05). However, inter-peak time between d1 and d2 in OD was significantly longer than that in OS (P=0.0491)

Conclusions: : Dysfunction of retinal ganglion cell under high IOP may result in the dysfunction of inner retina, including the function of Off-response represented by d1-wave in late-stage primate glaucoma.

Keywords: electroretinography: clinical • retina