Prevalence of Epiretinal Membrane and Macular Edema Across Uveitis Subtypes: A Retrospective Cross-Sectional Study

Background/Objectives: This study aimed to determine the prevalence of epiretinal membrane (ERM) and macular edema (ME) at initial presentation across clinically defined uveitis subtypes. Methods: In this retrospective cross-sectional study, we reviewed clinical records from the initial visit and imaging from 3879 eyes of 2559 patients diagnosed with uveitis at Tokyo Medical University Hospital between 2011 and 2021. The prevalence of ERM and ME was estimated overall and by uveitis subtype, with additional descriptive age- and sex-stratified analyses. Results: ERM and ME were identified in 185/3879 eyes (4.8%) and 235/3879 eyes (6.1%), respectively. Rare subtypes with very small sample sizes showed the highest crude prevalences; however, among uveitis subtypes represented by at least 30 eyes, sarcoidosis had the highest ERM prevalence (50/363 eyes, 13.8%). By contrast, Behçet's disease had the highest ME prevalence (44/284 eyes, 15.5%). In descriptive subgroup analyses, Behçet's disease accounted for a greater proportion of ERM and ME in male and younger patients. By contrast, sarcoidosis accounted for a greater proportion in female and older patients. Conclusions: The prevalence of ERM and ME at presentation varied across uveitis subtypes; of those represented by at least 30 eyes, sarcoidosis showed the highest prevalence of ERM, whereas Behçet's disease showed the highest prevalence of ME.