En-face optical coherence tomography in patients with epiretinal membrane: Intuitive method for predicting functional outcomes

Purpose:To evaluate the correlation between en-face optical coherence tomography (OCT) parameters and functional outcomes before and after idiopathic epiretinal membrane (ERM) surgery.Methods:This retrospective cohort study involved 80 eyes from 80 patients who underwent surgery for idiopathic ERM. Best-corrected visual acuity, metamorphopsia assessment (M-score), and OCT were assessed before surgery and six months after. The adhesive zone (A-zone) and retinal fold, a novel en-face OCT parameter reflecting inner retinal layer changes, were evaluated. Correlations between the area of A-zone and the number of retinal folds on en-face OCT images and other B-scan OCT parameters were evaluated regarding visual outcomes before and after ERM surgery.Results:The defect size of the ellipsoid zone, interdigitation zone, and external limiting membrane were significantly correlated with preoperative and postoperative 6-month best-corrected visual acuity (all P < 0.05). The central foveal thickness, A-zone area, number of marginal retinal folds, and fovea involvement in the A-zone were correlated with the preoperative and postoperative 6-month M-score (all P < 0.05). The A-zone area was significantly associated with the preoperative and postoperative 6-month M-score in a multiple linear regression model (P < 0.001, P = 0.008, respectively), and the number of marginal retinal folds was significantly associated with the preoperative M-score (P < 0.001) and marginally significantly with the postoperative 6-month M-score (P = 0.106).Conclusion:The A-zone area and the number of marginal retinal folds were significantly associated with the M-score before and after ERM surgery. These novel en-face OCT parameters can serve as a novel surrogate tool for predicting the functional outcomes in idiopathic ERM.