Quantitative ultra-widefield fluorescein angiography biomarkers in diabetic retinopathy and association with treatment and progression.

Purpose: To determine if demographic factors and calculated areas of nonperfusion (NP) and neovascularization (NV) on ultra-widefield (UWF) fluorescein angiography (FA) in the eyes of patients with diabetes are associated with treatment with intravitreal injections (IVIs), panretinal photocoagulation (PRP), and diabetic retinopathy (DR) progression.

Patients and methods: This retrospective, cross-sectional study included 363 patients (651 eyes) treated at the University of Michigan Kellogg Eye Center between January 2009 and May 2018. Eligible participants were 18 years or older diagnosed with diabetes who received UWF FA. Patients with previous PRP or poor-quality images were excluded. Main outcome measures included comparison analyses of measured surface areas in millimeters squared (mm²) of total and regional retinal nonperfusion and neovascularization, number of IVIs and PRP treatments, and DR progression.

Results: Our cohort received 3,041 IVIs and 878 PRP treatments with a mean follow-up of 915 days (SD ±714). IVIs were positively associated with posterior NP (difference, 1.15 mm²; 0.43-1.86; P=0.0017). PRP treatments were positively associated with total NP (difference, 27.24 mm²; 14.68-39.79; P<0.001) and total NV (difference, 1.75 mm²; 0.84-2.65; P<0.001), as well as regional areas. While progression was not associated with NP/NV area, it was positively associated with a pre-existing diagnosis of type 2 as compared to type 1 diabetes (147% increase; 7-373% increase; p=0.03).

Conclusion: Areas of NP and NV on UWF FA demonstrated associations with PRP and IVIs in DR patients.