Abstract
Purpose :
Current evaluation of DR relies heavily on grading of secondary vascular effects, such as microaneurysms and hemorrhages, by clinical examination instead of by evaluation of actual vascular changes. VESsel GENeration (VESGEN) is a 2D automated microvascular mapping and quantification software that provides an interactive interface that has been used to map and quantify vascular changes in DR (Parsons-Wingerter, 2010); however, a limitation of the previous study was the lack of comparisons of DR subjects with age-matched controls.
Methods :
Type 2 diabetics (n=8; 15 eyes) with an HgA1C of 6.2 to 10.5 and age-matched non-diabetic controls with HgA1C < 5.4 (n=8; 15 eyes) and age range from 25 to 52 years underwent retinal fluorescein angiography (FA). The diabetic cohort was grouped based on their DR level using modified ETDRS criteria and compared to controls. Vessel generations were determined and grouped based on vessel branching and dimeter into large (G1-3), medium (G4-5), and small (G≥6) vessels by VESGEN and output data from FA binary input images were analyzed using GraphPad
Results :
Unexpectedly, no age-related changes were observed in arterial and venous tortuosity, density, or a total number of vessels in the controls. Diabetic subjects (mild and moderate) showed significantly less vessel length (p=0.0047) and branchpoint density (p=0.0059) compared to controls among total vessels (macro and microvessels, arterial and venous). Tortuosity of the total arterial and venous macrovessels (G1-5) were not significantly different in retinas of the controls, mild DR, or moderate DR subjects. However total tortuosity of the arterial but not venous microvessels (G≥6) were significantly increased in both mild (p=0.0012) and moderate (p=0.006) DR when compared to controls. The total number of arterial but not venous microvessels (G≥6) were increased in both mild (p=0.001) and moderate (p=0.006) DR when compared to controls. The vessel density of both arterial and venous microvessels in the retina of the mild DR (p=0.024 and p<0.0001, respectively) and moderate DR (p=0.001 and p<0.0001, respectively) subjects were statistically significantly increased compared to controls.
Conclusions :
This study suggests that in microvessels (>G-5), vascular changes begin at mild DR. VESGEN with FA imaging may serve as an additional clinical tool for monitoring the small changes in progression of DR.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.