En Face OCT Imaging of Epiretinal Membranes Complicated by Internal Limiting Membrane Tears

Purpose: To describe the demographic, clinical and en face optical coherence tomography (OCT) features of eyes with epiretinal membrane (ERM) with or without internal limiting membrane (ILM) tears. Design: Retrospective case series. Methods: Single-institution study including 101 eyes of 101 patients with ERM. Demographic and clinical data were collected from the electronic medical record. En face OCT of the ERM was reviewed and studied in every case and the prevalence of ILM tears was determined. Various en face OCT biomarkers associated with ILM tears were also evaluated including nerve fiber layer defects (NFLD) which were classified as NFLD round (R), i.e. paravascular inner retinal defects (PIRDs), versus NFLD oval (O), i.e. inner retinal dimples (IRDs). Schisis of the retinal nerve fiber layer (SNFL) and posterior vitreous detachment (PVD) grade were also assessed. Results: ILM tears were identified in 21 of 101 eyes (20.8%) with ERM. No significant differences in demographic or clinical characteristics were observed between ERM eyes with or without ILM tears. However, NFLD (R) (i.e. PIRDs) were significantly (P < 0.05) more common (80.9% vs 37.5%) in the ILM tear group versus the non-ILM tear group. This was also the case for SNFL (57.1% vs 12.5%) and grade 4 PVD (100% vs 68.7%). Additionally, NFLD (O) (i.e. IRDs) were only present in the ILM tear group (52.4% vs 0%). Conclusions: Eyes with ILM tear exhibit several associated imaging biomarkers suggestive of progressive ERM contracture and/or vitreoretinal traction as compared to eyes without ILM tears including various forms of NFL defects and schisis of the nerve fiber layer. En face OCT, especially when widefield, may serve as a supportive tool to identify the various pathoanatomical lesions associated with ILM tears with single acquisition.