Visual and Anatomical Outcomes of Vitrectomy with ERM and ILM Peeling in Idiopathic and Secondary ERM

Background/Objectives: To evaluate the visual and anatomical outcomes of pars plana vitrectomy (PPV) with epiretinal membrane (ERM) and internal limiting membrane (ILM) peeling and to assess the impact of etiological differences on postoperative outcomes. Methods: This retrospective study included 57 eyes of 51 patients who underwent PPV for ERM, including 34 eyes with idiopathic ERM and 23 eyes with secondary ERM. Patients were classified as having idiopathic or secondary ERM based on clinical history, fundus examination, and optical coherence tomography (OCT) findings. Best-corrected visual acuity (BCVA), central macular thickness (CMT), foveal contour, intraoperative findings, and postoperative outcomes at 1, 3, 6, and 12 months were analyzed. Factors associated with final visual acuity were evaluated using correlation analyses and multivariate linear regression analysis. Results: The mean age of patients was 71.43 ± 6.46 years. BCVA improved significantly from 0.78 ± 0.35 logMAR preoperatively to 0.62 ± 0.44 logMAR at 12 months postoperatively (p = 0.004). Mean CMT decreased significantly from 411.68 ± 124.13 µm to 243.03 ± 89.25 µm at 12 months (p < 0.001). Improvement in foveal contour was observed in 70.2% of eyes; however, this anatomical improvement was not associated with better visual outcomes. In the multivariable analysis, preoperative BCVA was significantly associated with 12-month BCVA (p = 0.038), although the overall regression model did not reach statistical significance (p = 0.134). Although changes in BCVA and CMT did not differ significantly between idiopathic and secondary ERM groups, baseline BCVA-adjusted analysis showed significantly worse final BCVA in the secondary ERM group. Conclusions: ERM surgery with ILM peeling resulted in significant improvements in both visual and anatomical outcomes, supporting its effectiveness in achieving functional and anatomical improvement.