Risk Factors for Epiretinal Membrane After Rhegmatogenous Retinal Detachment Repair: Quantitative Ultra Widefield Imaging Analysis

Background and Objective: To utilize quantitative ultra widefield retinal imaging to investigate the risk factors associated with the incidence and severity of postoperative epiretinal membrane (ERM) in patients who underwent primary rhegmatogenous retinal detachment (RRD) repair. Patients and Methods: This retrospective study included patients who underwent pars plana vitrectomy (PPV) with scleral buckle (SB) for RRD, without a prior history of ERM, and who underwent ultra widefield imaging postoperatively between June 2020 and February 2022. The size and location (distance from the macula) of the drainage retinotomy and the area of peripheral pathology, including retinal breaks and laser scars, were quantitatively measured with cloud-based software. The severity of postoperative ERM formation at 6 months was graded from grade 1 to 4. We investigated the risk factors that were significantly associated with the incidence and severity of postoperative ERM at 6 months. Results: We included 80 eyes (80 patients) in this study. Postoperative ERM developed in 37 eyes (46%) at 6 months. The severity of ERM was grade 1 in 24 eyes (65%), grade 2 in 6 eyes (16%), grade 3 in 4 eyes (11%), and grade 4 in 3 eyes (8%). Postoperative ERM was not associated with the presence or the location of drainage retinotomy ( P = 0.836 and 0.820, respectively). However, it was significantly associated with larger surface area of drainage retinotomy ( P = 0.039). In addition, postoperative ERM was significantly associated with a larger area of peripheral pathology ( P = 0.012), a larger extent of RRD ( P = 0.013), vitreous hemorrhage ( P = 0.026), redetachment within 6 months ( P = 0.022), use of silicone oil as a tamponade ( P = 0.047), and number of surgeries within 6 months ( P = 0.027). These factors, in addition to 360° endolaser, were also significantly associated with the severity of postoperative ERM. In multivariable linear regression analysis, the only variable that remained statistically significant was the size of the drainage retinotomy ( P = 0.023). Conclusion: The pathogenesis of postoperative ERM is multifactorial. Large drainage retinotomies may increase the risk of ERM formation. [ Ophthalmic Surg Lasers Imaging Retina 2023;54:206–216.]