Morphometric Analysis of Epiretinal Membranes Using SD-OCT

Abstract

To determine whether the volumes of macular layers before and after epiretinal membrane (ERM) peeling as measured by spectral-domain optical coherence tomography (SD-OCT) correlated with best-corrected visual acuity (BCVA) or ERM location. Thirty-six eyes with idiopathic ERM and 12 control eyes were imaged preoperatively and postoperatively using SD-OCT. The inner, middle, and outer retinal layers were measured in the temporal and nasal half of the central 1,500 μm of the macula for each of the SD-OCT five raster scans and used to estimate the volumes for each group. The inner layer volumes were larger in cases compared with control eyes. The nasal inner and temporal inner layer volumes decreased after ERM removal in the nasal dominant, macular dominant, and temporal dominant groups. The inner layer volume decreased more temporally than nasally in the macular dominant and temporal dominant groups but not in the nasal dominant group. The volume decreased more in the temporal middle than the nasal middle layer for the temporal dominant group. The BCVA improvement correlated with nasal inner layer volume decrease and nasal outer and temporal outer layer volume increase. The volume of the inner perifoveal retinal sections decreases after ERM peeling, possibly representing resolution of edema or reorganization of the nerve fiber layer on release of mechanical traction. Visual improvement correlated with volume increase of the outer retinal layers and may represent photoreceptor cell recovery after ERM peeling.