Correlation between macular ganglion cell-inner plexiform layer thickness and visual acuity after resolution of the macular edema secondary to central retinal vein occlusion

AIM： To examine the thickness of the ganglion cell-inner plexiform layer（GCIPL） in eyes with resolved macular edema（ME） in non-ischemic central retinal vein occlusion（CRVO）, applying spectral-domain optical coherence tomography（SD-OCT）, and its relationship with visual acuity.METHODS： The retrospective observational case-control study included 30 eyes of non-ischemic CRVO patients with resolved ME（ME eyes） after treatment, and 30 eyes of non-ischemic CRVO patients without ME（non-ME eyes）. The macular GCIPL thickness, peripapillary retinal nerve fiber layer（p RNFL） thickness and central macular thickness（CMT） were measured on a SD-OCT scan. Linear regression analyses were performed to determine the correlation between the thickness of each and the visual acuity（VA）.RESULTS： No significant difference in average GCIPL thickness, mean pR NFL thickness and CMT were observed between ME group and non-ME group（P=0.296, 0.183, 0.846）. But, minimum GCIPL thickness was reduced in ME eyes compared with non-ME eyes（P=0.022）. Final VA significantly correlated with the minimum GCIPL thickness in ME eyes（r=-0.482, P=0.007）, whereas no correlation was found with average GCIPL thickness, average pR NFL thickness and mean CMT.CONCLUSION： Minimum GCIPL thickness is reduced in ME eyes compared with non-ME eyes, and correlated with the VA in non-ischemic CRVO. These results propose that inner retinal damage occurring in patients with ME secondary to non-ischemic CRVO may lead to permanent visual defect after treatment.