Analysis of ganglion cell-inner plexiform layer thickness in retinal vein occlusion with resolved macular edema

Purpose To analyze the retinal ganglion cell-inner plexiform layer (GCIPL) changes in retinal vein occlusion (RVO) eyes with resolved macular edema using optical coherence tomography. Methods We compared the average and minimum GCIPL thickness in RVO eyes with fellow eyes and healthy controls including 40 unilateral RVO patients and 48 healthy subjects. The average GCIPL thickness in BRVO eyes was segmented into the affected and opposite area according to the site of lesion, comparing them with corresponding areas in fellow eyes. Furthermore, maximum central macular thickness (CMT), visual acuity (VA), and intravitreal injection times were recorded to investigate their relationship with the GCIPL thickness. Results Despite no significant difference in CMT (P = 0.96), the average (P = 0.02 and P < 0.001, respectively) and minimum (both P < 0.001) GCIPL thicknesses were decreased in RVO eyes with resolved macular edema after treatment in comparison to fellow eyes and healthy eyes. Maximum CMT thickness was negatively correlated with the minimum GCIPL thickness (r = - 0.47, P = 0.003). VA and average GCIPL thickness were associated (r(s) = - 0.49, P = 0.002). In a subgroup analysis that only included BRVO patients, the opposite area revealed no significant difference between two eyes (P = 0.91) although the affected area in BRVO eyes was decreased (P < 0.001). Conclusions A decrease of GCIPL thickness in RVO was observed even after anatomic restoration and associated with VA prognosis. These GCIPL defects could be attributable to systemic risks and RVO itself, not anti-VEGF effects.