Abstract
Purpose :
Epiretinal membranes (ERM) cause disruption of the retinal mosaics, resulting in aniseikonia, metamorphopsia, and decreased visual acuity (VA). Binocular misregistration of the retinal mosaics may lead to central-peripheral rivalry (CPR)-type diplopia. We performed a prospective, cross-sectional study to characterize the prevalence and associations of CPR-type diplopia in patients with ERM.
Methods :
We recruited 38 patients with ERM, with (N=19) or without (N=19) macular comorbidity (excluding patients with wet macular degeneration, macular hole, and vein occlusion with macular edema). We classified diplopia based on history, diplopia questionnaire responses, and clinical exam. We tested VA, aniseikonia (subjective and New Aniseikonia Test), metamorphopsia (qualitative by door frame and Amsler grid; quantitative by M-Charts and D-Charts), ocular alignment, retinal misregistration (optotype-frame test and synoptophore central-peripheral superimposition slides). We defined clinical evidence of retinal misregistration as “double optotype single frame,” or vice versa, on the optotype-frame test or mismatched superimposition targets on the synoptophore. Confirmed CPR-type diplopia was defined as evidence of retinal misregistration, where other causes did not fully explain diplopia.
Results :
11 (29%) of 38 patients with ERM reported diplopia, with 7 of 11 having confirmed CPR-type diplopia. Interestingly, 16 (59%) of 27 patients without diplopia had evidence of retinal misregistration on clinical testing (16 by synoptophore, 2 also by optotype-frame test). Patients with CPR-type diplopia had better VA and greater metamorphopsia in the eye with the worst ERM than patients without diplopia (median logMAR: 0.1 vs 0.4, P=0.01; median M-chart score: 0.9 vs 0.3, P=0.008; qualitative frequency: 100% vs 63%, P=0.08; median D-Chart score: 2.1 vs 1.2, P=0.3). A greater proportion of patients with CPR-type diplopia had aniseikonia more than 5% (43% vs 22%, P=0.3).
Conclusions :
CPR-type diplopia is not uncommon in patients with ERM. Patients with CPR-type diplopia have better VA and more severe metamorphopsia than those without diplopia and possibly greater aniseikonia. Longitudinal studies are needed, with specific attention to diplopia, VA, metamorphopsia, and aniseikonia, to evaluate whether our findings have prognostic value for patients considering ERM surgery.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.