ASSOCIATION BETWEEN TANGENTIAL CONTRACTION AND EARLY VISION LOSS IN IDIOPATHIC EPIRETINAL MEMBRANE

Purpose: To investigate the clinical features associated with early visual loss in patients with idiopathic epiretinal membrane. Methods: Patients with idiopathic epiretinal membrane with visual acuity of >= 20/40, intact ellipsoid zone, and follow-up duration of at least 24 months were included in this retrospective age-matched control study. The disk-fovea-vascular (DFV) distance, central macular thickness, membrane configuration, and ellipsoid zone were assessed using fundus photography and spectral domain optical coherence tomography. Results: We analyzed the progression group (n = 15; vision loss >= 2 lines because of membrane progression) and the control group (n = 30; age matched). Compared with the controls, the mean DFV distance decreased (P < 0.001), central macular thickness increased (P = 0.017), and the ratio of the follow-up and baseline DFV distances (traction index of membrane) was significantly lower (P = 0.001) in the progression group. No differences were observed in the follow-up membrane configuration and ellipsoid zone. Factors associated with early vision loss were the DFV distance change (r = 0.657; P = 0.008) and traction index of membrane (r = 20.636; P = 0.011). Their area under receiver-operating characteristic curves were significant (DFV distant change: 0.915, traction index of membrane: 0.910, respectively; P < 0.001, both). Conclusion: Assessing the DFV distance is useful in quantifying the tangential contraction of macula and the prediction of vision loss in idiopathic epiretinal membrane.