Effects of Internal Limiting Membrane Peel for Idiopathic Epiretinal Membrane Surgery: A Systematic Review of Randomized Controlled Trials

The purpose of this study was to compare functional and anatomical outcomes after epiretinal membrane (ERM) peeling with internal limiting membrane (ERM/ILM) peeling and without for the treatment of idiopathic ERM. Systematic review and meta-analysis. A comprehensive search of Cochrane CENTRAL, MEDLINE Ovid, and Embase Ovid for randomized controlled trials comparing ERM/ILM with ERM was performed. Two independent reviewers selected papers and extracted data. Methodological quality was assessed using the Cochrane Risk of Bias (RobVis) tool. Data was analyzed using RevMan 5.3. Quality of body of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Seven studies reporting 387 eyes overall were included. A total of 207 eyes (53%) received ERM/ILM. A total of 180 (47%) received ERM. Post-operative visual acuities (logMAR) were not significantly different between ERM/ILM and ERM, with a mean difference (MD) of 0.02 (95% confidence interval [CI]: −0.04 to 0.09; P = .45; I2= 42%; n = 101) at 1 month; 0.03 (95% CI: −0.01 to 0.06; P = .11, I2 = 15%; n = 299; High Certainty of Evidence) at 3 months; 0.01 (95% CI: −0.03 to 0.04; P = .72; I2 = 21%; n = 317; High Certainty of Evidence) at 6 months; and 0.01 (95% CI: −0.02 to 0.04; P = .49; I2 = 39%; n = 234) at 12 months post-operatively. ERM/ILM was significantly associated with lower ERM recurrence at 6-12 months with a relative risk of 0.16 (95% CI: 0.04-0.64; P = .01; I2 = 0%; n = 155; Moderate certainty of evidence) and an increased central macular thickness (micrometers) at 12 months with an MD of 20.53 (95% CI: 4.96-36.09; P = .01; I2 = 12%; n = 234). ERM/ILM and ERM result in similar visual acuity despite subtle differences in anatomical outcomes (central macular thickness). ERM/ILM is associated with a significantly lower rate of ERM recurrence at 6-12 months post-operatively and should be considered where recurrence prevention is the treatment priority.