The retinal vessel response to flicker light in patients with central retinal vein occlusion

Abstract Purpose: The study examined the retinal vessel diameter (A/V Ratio) and the response to flicker light in patients with central retinal vein occlusion and in patients with arterial hypertension. Methods: The prospective study included 30 patients. In the group I. were 12 patients with central retinal vein occlusion (CRVO), in group II. 10 patients with hypertension and in group III. 8 healthy volunteers. A/V ratio (static analysis) and the diameter response of an arterial and venous vessel segment to flicker light (dynamic analysis) were measured with a Retinal Vessel Analyzer. Each dynamic examination consisted of a 50 s baseline measurement and three periods of 20‐s flicker light provocation followed by 80 s observation. The mean of three flicker cycles was calculated as dynamic vessel response. Results: Statistically significant differences of A/V ratio were observed in the static vessel analysis between groups I.‐III. (A/V ratio: 0.71±0.07; 0.76±0.06 and 0.82±0.02 respectively). The dynamic analysis showed statistically significant differences in arterial dilatation and constriction between all investigated groups as well. The venous flicker response showed significant differences between healthy controls (group III.) and group I. and II. No significant differences in venous response were measured between group I. and II. Conclusions: The results show significant differences in A/V ratio and arterial response to flicker stimulation in patients with CRVO. We suppose that the degree of retinal vessels endothelial dysfunction is one of the leading factors in the ethiopathology of central retinal vein occlusion.