Baseline visual acuity and interdigitation zone as predictors in idiopathic epiretinal membranes: A retrospective cohort study

Abstract

Objective: Determine which functional and anatomical characteristics may be predictors of final visual acuity in patients with idiopathic ERM (iERM) submitted to pars plana vitrectomy (PPV) with ERM and internal and internal limiting membrane (ILM) peeling. Design: Retrospective cohort study. Subjects: Patients with iERM submitted to PPV between 2016 and 2017. Methods: Data regarding the best-corrected visual acuity (BCVA) and the characteristics of the retinal layers observed in SD-OCT were collected preoperatively and until 12 months postoperatively. Central macular thickness (CMT), disorganization of the retinal inner layers (DRIL), outer nuclear layer (ONL) thickness, integrity of subfoveal external limiting membrane (ELM), ellipsoid zone (EZ), and interdigitation zone (IZ) were evaluated. Results: A total of 128 eyes with iERM from 121 patients were included. BCVA improved significantly ( p < 0.001). Significant improvement of BCVA, CMT, DRIL, ONL, ELM, and EZ were obtained. The final IZ was not different from baseline until the end of the study. A significant correlation was observed between the baseline BCVA, EZ, IZ, and the postoperative BCVA ( p < 0.001). However, only the baseline BCVA and the integrity of the subfoveal baseline IZ were predictive factors for final BCVA ( p < 0.005 and p < 0.001, respectively). Conclusion: PPV provides a significant improvement of BCVA and retinal anatomy recovery in iERM eyes. Baseline IZ didn’t change during the 12 months following surgery. Baseline BCVA and subfoveal IZ at baseline were prognostic factors for the final BCVA.