Bare retinal nerve fiber layer and internal limiting membrane tear associated with epiretinal membrane: OCT findings and visual outcomes.

Abstract

This study aims to describe spectral-domain optical coherence tomography (OCT) characteristics and assess surgical outcomes for bare retinal nerve fiber layer (RNFL) and internal limiting membrane (ILM) tear associated with the epiretinal membrane (ERM). This retrospective study comprised 158 consecutive patients with idiopathic ERM with (group A) or without (group B) bare RNFL (19 and 139 patients, respectively) who underwent vitrectomy between March 2016 and May 2019. Surgical videos and pre- and postoperative OCT images were reviewed to characterize bare RNFL and ILM tear and analyze postoperative visual outcomes. Typically, the torn ILM is seen as a mono- or multi-layered thin scrolled membrane in OCT, correlated frequently with areas of RNFL schisis. On the near-infrared fundus images, a hypo-reflective band corresponding to rolled-up edge of torn ILM and ERM was identified. The bare RNFL area was located adjacent to and peripheral to this band and showed a less-wrinkled retina preoperatively. Mean logMAR BCVA and central foveal thickness (CFT) progressively improved in both groups. However, group A had greater mean CFT change than group B (P = 0.001). Typical appearances of bare RNFL and ILM tear associated with ERM were identified. Thorough evaluation of preoperative OCT is important for vitreoretinal surgeons to recognize bare RNFL and ILM tear to minimize surgical trauma.