Wide-field swept-source OCTA in the assessment of retinal microvasculature in early stage diabetic retinopathy

Abstract

Abstract Background: To perform a quantitative analysis of retinal microvasculature in patients with early stage diabetic retinopathy (DR) using wide-field swept-source OCTA (SS-OCTA).Methods: 119 eyes of 119 patents (67 eyes with no DR and 52 eyes with mild-moderate NPDR) were enrolled in this observational and cross-sectional cohort study, and an age-matched group consisting of 39 eyes of 39 non-diabetic subjects were set as the control. Each participant underwent a full ophthalmic examination, including wide-field SS-OCTA imaging. On OCTA scans (12mm * 12mm), the mean perfusion area (PA) and vessel density (VD) were independently measured in all 16 Early Treatment Diabetic Retinopathy Study (ETDRS) sectors. Linear regression analyses were conducted to evaluate the influences of PA.Results: In the central ring, there were no significant differences in the average PA and VD among the groups. In the 3 mm radius, the PA and VD of the no DR and mild-moderate NPDR were significant decreased compared with the control group in superior and inferior quadrants. In the wide-field scans (9 and 12mm radius), there was no significant difference in average PA and VD between the groups in each sectors (p>0.05). Regression analysis found that the effect of VD on PA was statistically different (p<0.001).Conclusion: Wide-field SS-OCTA allows for a more thorough assessment of retinal changes in patients with early-stage DR. Decrease in PA and VD was greater in the S3 and I3 sectors, and reductions in PA and VD were uneven in wide-filed sectors (9 and 12mm radius).