Quantitative Assessment of Microvascular Changes in Diabetic Retinopathy and Their Association With Blood-Retinal Barrier Impairment

ObjectiveTo quantitatively evaluate retinal microvascular changes in patients with diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA), and to explore their association with blood-retinal barrier (BRB) disruption. MethodsA total of 208 patients with type 2 diabetes and DR underwent OCTA to obtain microvascular parameters. Serum vascular endothelial growth factor (VEGF) and intercellular adhesion molecule 1 (ICAM-1) levels were measured. Correlations were analyzed, risk factors were identified using logistic regression, and diagnostic efficacy was evaluated with ROC curves. ResultsThe superficial capillary density (SCP-D) and deep capillary density (DCP-D) of the 208 DR patients were (42.67 ± 4.35)% and (47.89 ± 5.02)%, respectively. The mean values for the area, perimeter, and circularity index of the foveal avascular zone (FAZ) were (0.38 ± 0.10) mm², (2.04 ± 0.28) mm, and 0.72 ± 0.08, respectively. The mean area of the non-perfusion zone was (1.87 ± 0.45) mm². Among these patients, 121 (58.17%) cases had abnormal SCP-D (r = 0.559, 95% CI: 0.457-0.661) and ICAM-1 (r = 0.411, 95% CI: 0.289-0.533). The FAZ circularity index, SCP-D, and DCP-D were negatively correlated with VEGF and ICAM-1 (P P ConclusionThe OCTA assessment indicators in DR patients are closely related to BRB-related markers. The area of the non-perfusion zone has the highest predictive value for severe retinal microvascular changes in DR patients.