The Effect of Internal Limiting Membrane Cleaning on Epiretinal Membrane Formation after Vitrectomy for Proliferative Diabetic Retinopathy

Purpose: We hypothesised that cleaning the internal limiting membrane (ILM) with a flexible nitinol loop following diabetic vitrectomy without peeling may reduce the common occurrence of postoperative epiretinal membrane (ERM) formation. Methods: Consecutive patients undergoing vitrectomy for proliferative diabetic retinopathy by one surgeon from 2015 to 2019 were studied and divided into 2 cohorts: the control group underwent standard surgery, and the ILM clean group underwent additional cleaning of the macular retina using a flexible nitinol loop after vitrectomy. Masked comparison of ERM on optical coherence tomography was performed at 3 months, and visual acuity (VA) was measured until 12 months postoperatively. Results: Baseline demographics, clinical features, and protein levels were similar between cohorts. The ILM clean group (n = 56) had fewer clinically significant ERM than the control group (n = 50; 4 vs. 20%; p = 0.01), and a significantly lower proportion of the ILM clean group required revision surgery (2 vs. 14%; p = 0.02). VA in the ILM clean group was significantly better than in the control group at 3 months (0.35 vs. 0.50 logMAR; p = 0.02) but not at 12 months (0.34 vs. 0.43 logMAR; p = 0.17). Conclusion: ILM cleaning with a flexible nitinol loop following diabetic vitrectomy resulted in significant reduction in ERM formation and reduced necessity for revision surgery. There was significant improvement in VA at 3 months but not over a longer follow-up.