Evolution of Subfoveal Detachments Secondary to Idiopathic Epiretinal Membranes after Surgery.

Purpose To study the characteristics of subfoveal abnormalities secondary to idiopathic epiretinal membranes (ERM) using improved-resolution spectral-domain optical coherence tomography (SD OCT) and their evolution after surgery. Design Retrospective, observational cohort study. Participants The files of 344 patients operated on consecutively for ERM over a 2-year period in a single tertiary ophthalmologic center were reviewed. Patients with vitreomacular traction syndrome, secondary ERM, or both were excluded. Methods In all, 293 eyes with idiopathic ERM were included in the final analysis. Fundus photographs were reviewed to assess the presence of a yellow foveal spot, and SD OCT analysis was performed. Main Outcome Measures Presence or absence of a subfoveal abnormality and its SD OCT characteristics before and after surgery at 1 month, 3 months, and at final visit; best-corrected visual acuity (BCVA) and central macular thickness at baseline, 1 month, 3 months, and at the final visit. Results Before surgery, a subfoveal detachment (SD) corresponding to the yellow deposit was present in 59 of 293 eyes (20%). No difference was found for the postoperative BCVA between the 59 eyes with SD before surgery and the 234 eyes without SD (0.253 ± 0.14 logarithm of the minimum angle of resolution [logMAR] vs. 0.262 ± 0.24 logMAR, respectively; P  = 0.6). Sixty-eight percent (n = 40/59) of SD disappeared after surgery during a mean follow-up of 4.8 ± 3.2 months, most of them (62%) before month 3. Among eyes with preoperative SD, no difference was found for the postoperative BCVA between eyes with disappeared SD and those with persistent SD. Conclusions Subfoveal detachments secondary to idiopathic ERM were observed in 20% of these eyes. They disappeared after surgery in more than two thirds of cases, usually early during postoperative course. Subfoveal detachments do not affect visual outcome and should not interfere with surgical decision making.