Anatomical and functional significance of ectopic inner foveal layer (EIFL) in epiretinal membrane (ERM)

Abstract

To compare the visual acuity outcomes after surgical treatment of epiretinal membranes (ERM) in cases with and without ectopic inner foveal layers (EIFL). : A total of 100 eyes of 98 patients with idiopathic ERM were retrospectively staged according to the newer OCT classification and divided into two groups on the basis of presence or absence of EIFL. The two groups were evaluated for various parameters including visual acuity, thickness of the EIFL, re-appearance of the foveal contour, outer retinal changes and complications before and after ERM peeling. Correlation analysis was done using chi square test and p-values were obtained for corresponding variables.: Of 100 eyes with ERM, 20% had stage 1, 29% had stage 2, 42% had stage3 & 9% had stage 4 disease. VA was worse in eyes with EIFL as compared those without it. Correlation of VA with EIFL thickness however was not significant. Surgical removal of ERM didn’t alter EIFL frequency though the thickness decreased. New EIFL appeared in 4% eyes and 35% demonstrated thickened fovea after surgery. Anatomical reappearance of foveal contour was poorer in eyes with EIFL. Outer retinal changes were more common in non EIFL eyes. Lamellar holes and nontractional cysts were more common in EIFL eyes.: EIFL is a significant prognostic tool to predict the visual outcome of surgery in cases of Epiretinal membrane. EIFL eyes did not regain foveal contour, had less outer retinal damage but were associated with poorer visual outcomes.