Spectral-Domain Optical Coherence Tomography for Monitoring Epiretinal Membrane Surgery

Purpose: To assess prognostic factors in epiretinal membrane (ERM) surgery using spectral-domain (SD) optical coherence tomography (OCT). Design: Prospective, interventional case series. Participants: Forty-one patients. Methods: Patients with a diagnosis of ERM were examined with spectral-domain and time-domain (TD) OCT before and after surgery. Main Outcome Measures: Main outcome measures were functional results and predefined OCT patterns. Cofactors analyzed were the type of ERM, the duration and grading of subjective metamorphopsia, simultaneous cataract surgery, the type of dyes used, the duration of surgery, gender, and age. A multivariate regression analysis was performed. Results: Thirty-nine patients (95%) showed an improved or stable best-corrected distance visual acuity (DVA) at 3 months, whereas 36 patients (88%) showed an improved or stable best-corrected near visual acuity (NVA) at 3 months. Significant correlations (P>0.4) were found between the course of central retinal thickness (CRT) assessed using SD OCT and TD OCT (P<0.02). No clinically relevant correlations (P<0.3) were seen between CRT and VA (P>0.1). Baseline DVA and NVA were found to be significant prognostic values for the postoperative decrease in CRT in both OCT systems (P<0.04) as well as for the visual outcomes (P<0.007) at 3 months. In addition, the integrity of the junction between the photoreceptor inner segment and outer segment (IS/OS) significantly influenced the visual outcomes at 3 months (P<0.038). The baseline profile of the internal limiting membrane (ILM) significantly influenced the NVA at 3 months (P<0.009), whereas the postoperative foveal contour significantly influenced the DVA at 3 months (P<0.025). The type of ERM, subjective metamorphopsia, simultaneous cataract surgery, the type of dyes used, the duration of surgery, gender, or age had no significant influence on patient outcome (P>0.05). Compared with TD OCT, SD OCT allowed for a more precise differentiation between the ERM and the retinal surface and for a better evaluation of the IS/OS line. Conclusions: Besides the baseline VA, the integrity of the IS/OS line, better visualized by SD OCT, can be used to predict the functional outcomes after surgery. Additionally, analyzing the ILM profile and the foveal contour may help to understand limited visual outcomes after surgery. Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article. Ophthalmology 2010;117:798-805 (C) 2010 by the American Academy of Ophthalmology.