Stage of Epiretinal Membrane and Central Bouquet Abnormalities: Key Predictors of Visual Acuity After Vitrectomy.

PURPOSE: To investigate the long-term visual outcome after vitrectomy for idiopathic epiretinal membrane (ERM) according to the preoperative stage of the disease, focusing on central bouquet abnormalities (CBA). METHODS: Our retrospective study included 280 eyes of 241 patients with idiopathic ERM who underwent pars-plana-vitrectomy (PPV) with membrane peeling (MP) and internal limiting membrane (ILM) peeling between 2016 and 2021. The best corrected visual acuity (BCVA) in logMAR, the central bouquet abnormalities (CBA), and the thickness of the ectopic inner foveal layer (EIFL) were documented using spectral-domain optical coherence tomography (SD-OCT) one day before surgery, 6 weeks, 6 months, and at the last available follow-up after surgery. RESULTS: Mean BCVA improved significantly at each postoperative follow-up compared to baseline (p<0.001). Patients with stage 2 ERM showed the greatest improvement in BCVA compared to other patients (p<0.001). The postoperative visual outcome has been negatively affected by higher ERM stage (p<0.001), preoperative presence of subfoveal detachment (SFD) (p=0.033), preoperative presence of vitelliform lesions (VL) (p=0.021), and the presence (p<0.001) and thickness (p<0.001) of EIFL. CONCLUSION: The earlier surgical treatment of ERM at stage 2 may result in better visual outcomes and a greater increase in vision. The preoperative presence of central bouquet abnormalities and thick ectopic inner foveal layer is associated with worse postoperative visual results.