Epiretinal membrane prevalence in asymmetrical pseudoexfoliation glaucoma and its impact on glaucoma monitoring parameters including peripapillary vessel density.

PURPOSE: To determine the prevalence of epiretinal membrane (ERM) in asymmetrical pseudoexfoliation glaucoma (PXG) and to assess its impact on glaucoma monitoring parameters, including peripapillary radial capillary vessel density (RPC-VD) and macular vessel density (VD). STUDY DESIGN: Prospective, cross-sectional study. METHODS: The study included 160 eyes from 80 patients with asymmetrical PXG (PX material present in only one eye) and 80 right eyes from age-matched patients with primary open-angle glaucoma (POAG). All participants underwent optical coherence tomography angiography (OCTA) imaging. Differences between PXG, PX-negative fellow eyes, and POAG eyes were analyzed using generalized linear mixed models (GLMMs) to account for inter-eye dependency. RESULTS: There were no significant differences between PXG and POAG eyes in terms of age, visual field mean deviation (VF-MD), retinal nerve fiber (RNFL), ganglion cell complex (GCC), RPC-VD or most macular VD parameters (all p > 0.05). However, PXG eyes had a significantly higher risk of ERM than POAG eyes (OR = 5.60, 95% CI: 1.75–17.88, p = 0.004), after adjustment for age, sex, cataract and/or glaucoma surgery, diabetes, hypertension, and prostaglandin use. PX-negative fellow eyes exhibited an intermediate ERM prevalence, higher than in POAG eyes but not significantly different from either PXG or POAG eyes. Among PXG eyes, those with ERM had worse VF-MD (median: -7.62 dB vs. -2.53 dB, p = 0.008) and lower average RPC-VD and macular VD (p < 0.001– 0.008), while RNFL and GCC thicknesses were comparable. CONCLUSION: PXG was associated with a higher prevalence of ERM, and PX-negative fellow eyes may represent an intermediate stage within the pseudoexfoliation spectrum. In PXG eyes, the presence of ERM was associated with worse VF-MD, and reduced RPC-VD and macular VD. Detailed macular imaging and OCTA evaluation may improve the interpretation of VF changes and support clinical follow-up.