PURPOSE: To investigate the association between baseline clinical characteristics of patients with diabetic macular edema (DME) and quantitative intravenous fluorescein angiography (IVFA) parameters. METHODS: Consecutive patients with DME presenting with a central macular thickness (CMT) ≥310 µ m were recruited from 2017 to 2023. Ultra-widefield IVFA images were analyzed with the RETICAD algorithm to extract quantitative measures of blood-retinal barrier (BRB) permeability, retinal perfusion, and blood flow. Univariable and multivariable regression models were used to investigate associations between IVFA parameters and baseline best-corrected visual acuity (BCVA), CMT, and macular volume. RESULTS: The study population consisted of 56 eyes with DME, and seven eyes from healthy controls. In our multivariable analysis, BRB permeability measured in the central and peripheral retina was significantly associated with BCVA ( P = 0.003 and 0.002, respectively) and macular volume ( P = 0.025 and 0.045, respectively). Both central and peripheral BRB permeability were significantly higher in DME eyes relative to healthy controls ( P <
0.002). CONCLUSION: Increased BRB permeability measured on IVFA in DME eyes was associated with a greater baseline macular volume and worse BCVA, suggesting its potential in providing an objective assessment of disease severity. Future research should explore the clinical utility of quantitative IVFA measurements in diverse patient populations.