Quantification of retinal traction caused by epiretinal membrane (ERM) using en face optical coherence tomography and its influence on visual function.

Abstract

Purpose : Retinal traction caused by epiretinal membrane (ERM) is thought to be a cause of visual disturbance. However, it is difficult to quantitatively analyze the strength of retinal traction and to clarify its relationship with visual function. In this study, we quantified the strength of retinal traction using en face optical coherence tomography (OCT) and retrospectively studied its relationship with visual acuity and metamorphopsia.

Methods : Sixty-six eyes of 64 ERM patients (22 males and 42 females; mean age, 72.4±8.55 years old) were included in this study. Three dimensional OCT images were obtained using swept-source OCT (DRI OCT-1, Topcon), and en face OCT images were constructed using EnView software (Topcon). To quantify retinal traction, we visualized the retinal folds with en face OCT and measured the distance between the inner limiting membrane (ILM) and the deepest point of the retinal fold (maximum retinal fold depth). We also measured central retinal thickness (CRT) using B-scan OCT and quantified the degree of metamorphopsia using M-chart scores. We then investigated the correlation between maximum retinal fold depth and CRT and visual acuity or metamorphopsia (maximum M-chart score). Furthermore, we investigated the effect of residual retinal folds on visual acuity and metamorphopsia at 1 month after vitrectomy with ERM peeling using paired t-tests.

Results : Retinal folds were found in 59 eyes (89%). There was a significant correlation between maximum fold depth and maximum M-chart values and between CRT and maximum M-chart values (r²=0.378 and 0.433, respectively; both P<0.001). Neither maximum fold depth nor CRT was found to be correlated with visual acuity (P=0.587 and 0.216, respectively). ERM peeling was performed in 52 eyes, and retinal folds remained in 7 eyes (13%) at 1 month after surgery. The maximum M-chart value was significantly higher in cases with residual retinal folds than in those without retinal folds (P=0.016). There was no significant correlation between the presence or absence of residual retinal folds and visual acuity (P=0.977).

Conclusions : Retinal traction caused by ERM is significantly related to metamorphopsia but not to visual acuity. Maximum retinal fold depth and CRT may be quantitative indicators of retinal traction.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.