Assessment of macular profile using optical coherence tomography after epiretinal membrane surgery

Purpose: The aim of this study was to analyze the quality and functional result of epiretinal membrane (ERM) surgery using optical coherence tomography (OCT). Patients and method: We conducted a retrospective, non comparative study between January 2004 and June 2006. Thirty-two eyes were included and operated by vitrectomy for ERM. The OCT assessment of the macular profile was evaluated postoperatively on day 8, day 30 and every 3 months thereafter, The first outcome measure was postoperative abnormality of the OCT profile. The secondary outcome measure was analysis of the functional result with macular thickness and best visual acuity. The Student t-test and the paired series comparison were used for the statistical analysis. Results: After surgery, 23 eyes (72%) showed abnormality of the reflectivity signal as assessed by OCT. Only nine eyes (28%) had or showed restored foveal depression and normal macular thickness. Dissociated optic nerve fiber layer appearance was observed in 43.7% (14 eyes). The best visual acuity increased from 0.58 +/- 0.23 LogMar to 0.25 +/- 0.24 after ERM surgery (p < 0.001). The macular thickness decreased from 374.6 +/- 78.7 mu m to 271 +/- 44.6 mu m postoperatively (p < 0.001). Conclusion: Epiretinal membrane surgery is safe and effective in terms of the functional result but most cases do not recover normal microanatomy. This feature does not influence the functional result. Mechanical traction due to peeling of the epiretinal membrane associated with peeling of the internal limiting membrane may be the cause of these microanatomical results.