Purpose: To investigate the incidence and predictors of visual acuity (VA) loss after surgery for epiretinal membrane (ERM) in glaucomatous eyes.
Methods: A prospective cohort study examining VA and central visual fields (VFs, Humphrey 10-2) at baseline and 3, 6, and 12 months after vitrectomy with internal limiting membrane peeling for ERM in the glaucoma (47 eyes of 43 patients) and control (46 eyes of 46 patients) groups. VA and VF tests were repeated for ≥1.5 years only for the glaucoma group. Factors associated with substantial VA loss [>0.2 logMAR (about >2 lines on the Snellen chart) from baseline] were determined using a Cox proportional hazards model.
Results: Until 1 year postoperatively, no substantial VA loss occurred and postoperative VA improved significantly and similarly in both groups (P<0.001 vs. baseline, P>0.15 between two groups). Substantial VA loss occurred in eight eyes (17%) with glaucoma ≥1.5 years postoperatively, which was associated with worse preoperative VF mean deviation and 1-year mean decrease in postoperative VF mean deviation (hazard ratio = 0.83, 0.72; P = 0.018, <0.001, respectively).
Conclusions: Substantial VA loss occurred long after ERM surgery in eyes with glaucoma, which was associated with worse preoperative central VFs and greater central VF deterioration during the first postoperative year.