Optical Coherence Tomography Angiography–Based Evaluation of Foveal Avascular Zone and Macular Vessel Density in Prediabetic Patients

Background: To assess macular layer thickness, macular vessel density, and foveal avascular zone (FAZ) parameters in prediabetic patients compared with healthy normoglycemic controls using optical coherence tomography angiography (OCTA). Methods: Thirty prediabetic patients (group A; fasting plasma glucose 100-125 mg/dL, postprandial plasma glucose 140-199 mg/dL, glycated hemoglobin 5.7%-6.4%) and 30 age-matched normoglycemic subjects (group B) were included. The OCTA imaging was used to evaluate superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel densities, as well as FAZ area and perimeter. Participants with poor image quality, high refractive error, glaucoma, prior intraocular surgery, chorioretinal atrophy, or other ocular/sys-temic comorbidities were excluded. Results: The SCP and DCP perfusion densities (PDs) were lower in the prediabetic group, with significant reductions in the inferior and temporal quadrants of the DCP and the temporal quadrant of the SCP (P <.05). The FAZ area and perimeter were larger in the prediabetic group but not statistically significant (P >.05). Macular thickness was greater in all quadrants in group A, with significant thickening in the nasal and inferior quadrants (P <.05). Conclusion: Prediabetic patients demonstrated early microvascular and structural changes, including reduced macular PD, increased macular thickness, and FAZ enlargement. These findings suggest subclinical retinal involvement in prediabetes, warranting larger longitudinal studies. © 2026, AVES. All rights reserved.