Abstract
Purpose :
To investigate the clinical findings associated with early visual loss in the idiopathic epiretinal membrane (ERM) patients with good visual acuity
Methods :
Idiopathic ERM patients with logMAR 0.2 unit or better were divided into the progression group and the control. The progression group was defined as the vision loss of two lines or more due to membrane progression over 2 year follow period. The best corrected visual acuity (BCVA), the disc-fovea-vascular (DFV) distance, central macular thickness (CMT), membrane configuration, and ellipsoid zone (EZ) of photoreceptor cell layer were assessed retrospectively using fundus photograph and spectral domain optical coherence tomography. Traction Index of Membrane (TIM) was calculated as the follow-up DFV distance divided by the baseline one.
Results :
Fifteen eyes were in the progression group and 50 in the control group. The mean follow- up period was 31.1 ± 13.5 (24 ~ 73) and 38.0 ± 16.0 (24 ~72) months in both groups. The mean DFV distance decreased significantly from 14966.27 ± 974.41 µm to 14691.13 ± 918.66 µm in the progression group (p<0.001) but did not in the control group. The mean TIM of the progression group was 0.981, which was smaller than 0.992 of the control group (p=0.002). The progression group showed that the membrane configuration changed significantly (p=0.01), but the control group did not. The mean CMT and EZ status did not change in both groups. The area under the receiver operating characteristic curve for vision loss of ≥ 2 lines was significant for TIM (0.910; p =0.04). The cutoff value was 0.989 on the TIM.
Conclusions :
Shortening of the DFV distance may precede the macular thickening and the EZ damage in process of membrane progression. Tangential contraction of membrane itself can cause the early vision loss in the idiopathic ERM.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.