Preoperative study of the inner segment/outer segment junction of photoreceptors by spectral-domain optical coherence tomography as a prognostic factor in patients with epiretinal membranes

Objective: to demonstrate whether the preoperative integrity of the inner segment/outer segment (IS/OS) junction of photoreceptors studied by spectral-domain optical coherence tomography (SD-OCT) is a prognostic factor in epiretinal membrane surgery. Methods: we retrospectively studied patients with an idiopathic epiretinal membrane who underwent a 23-gauge vitrectomy to remove this membrane. Best-corrected visual acuity (BCVA) and SD-OCT scans were examined before and 6 months after the surgery. We studied the retinal microstructure, especially the IS/OS junction of the photoreceptors, and evaluated the intergroup differences between patients with an intact layer and those with an irregular or disrupted layer. We applied both the Wilcoxon and Mann-Whitney tests for statistical analysis. Results: in total, 51 eyes from 51 enrolled patients were examined in this study. The postoperative BCVA was significantly better for eyes that had an intact IS/OS junction than for eyes that had an irregular or disrupted IS/OS junction, as preoperatively observed with SD-OCT scans (P < 0.001). We also observed an important association between disrupted IS/OS junctions and the presence of cystic macular edema (P < 0.01). Conclusion: the presence of an intact IS/OS junction on the preoperative SD-OCT scan was an important predictor of better visual recovery after epiretinal membrane surgery.