The differences of horizontal optic disc diameter and cup/disc ratio in eyes with different kinds of retinal vein occlusion

Abstract

Objective To observe the differences of horizontal optic disc diameter and cup/disc (C/D) ratio in eyes with different kinds of retinal vein occlusion (RVO).Methods A total of 392 eyes from 385 RVO patients diagnosed by fundus fluorescein angiography (FFA) were included in this study.The patients included 192 males and 193 females.The average age was (58.30±11.51) years.The disease duration was from 7 days to 1 month.The eyes were divided into RVO group (356 eyes),RVO combining diabetes mellitus (DM) group (20 eyes) and RVO combining high blood pressure (HP) group (16 eyes).One hundred normal eyes examined by FFA in the same testing period were selected as the control group.Among the 356 eyes in the RVO group,there were 201 eyes with branch RVO (BRVO),100 eyes with central RVO (CRVO),17 eyes with hemi CRVO (H-CRVO),and 38 eyes with macular BRVO (M-BRVO).Among the 101 non-ischemic RVO eyes,there were 17 eyes with BRVO,53 eyes with CRVO,6 eyes with H-CRVO,and 25 eyes with M-BRVO.Among the 255 ischemic RVO eyes,there were 184 eyes with BRVO,47 eyes with CRVO,11 eyes with H-CRVO and 13 eyes with M-BRVO.The diameter of optic cup and disk,and the C/D ratio was measured on fundus infrared radiation (IR) IR30°image by Heidelberg confocal laser fundus imaging system.Results There was no significant difference of horizontal optic disc diameter among 4 groups (F=1.17,P＞0.05).The difference of C/D ratio was significant among 4 groups (F=82.24,P＜0.05).The differences of horizontal optic disc diameter and C/D ratio in different kinds of RVO in normal group and RVO group were significant (F=4.49,61.396; P＜0.05).The horizontal optic disc diameter of eyes with CRVO was a little smaller than normal eyes (P＜0.05).There was no difference of horizontal optic disc diameter between the eyes with BRVO,M-BRVO,H-CRVO and normal eyes (P＞0.05).The difference of C/D ratio was significant between the eyes with BRVO,CRVO,M-BRVO,H-CRVO and normal eyes (P＜0.05).The differences of horizontal optic disc diameter and C/D ratio were significant between RVO group (in different kinds of RVO eyes) and control group (F=3.94,33.16; P＜0.05).Compared the horizontal optic disc diameters of RVO eyes with the same subtype,the difference was significant between non-ischemic H-CRVO and ischemic H-CRVO (P＜0.05),while the differences were not significant between other non-ischemic RVO and ischemic CRVO (BRVO:P=0.35,CRVO:P =0.86,M-BRVO:P=0.22).The difference of C/D ratio between non-ischemic RVO and ischemic CRVO was not significant (BRVO:P=0.35,CRVO:P=0.48,H-CRVO:P=1.00,M-BRVO:P=1.00).Conclusions The C/D ratio increased with varying degrees in RVO eyes.There is no obvious change in horizontal optic disc diameters except for CRVO eyes. Key words: Retinal vein occlusion/etiology; Optic disk