ASSESSMENT of RETINAL BLOOD FLOW in DIABETIC RETINOPATHY USING DOPPLER FOURIER-DOMAIN OPTICAL COHERENCE TOMOGRAPHY

Purpose: To evaluate retinal blood flow measurements in normal eyes and eyes with varying levels of diabetic retinopathy (DR) using Doppler Fourier-domain optical coherence tomography (FD-OCT). Methods: Twenty-two eyes of 19 subjects, 10 with severe nonproliferative DR (NPDR) and 12 with proliferative DR (PDR), were compared with 44 eyes of 40 healthy control subjects. All eyes were scanned by RTvue FD-OCT. Color disk photographs and cube/volume scans of the optic nerve head were obtained. Doppler OCT scans and accessory imaging data were imported into Doppler OCT of Retinal Circulation grading software to calculate TRBF and vascular parameters (e.g., venous and arterial cross-sectional area). Measurements were compared between cases and controls using independent t-tests. Results: Mean TRBF was 44.98 ± 9.80 (range: 30.18-64.58) μL/minute for normal eyes, 35.80 ± 10.48 (range: 20.69-49.56) μL/minute for eyes with severe NPDR, and 34.79 ± 10.61 (range: 16.77-48.9) μL/minute for eyes with PDR. Mean TRBF was significantly lower in eyes with severe NPDR (P = 0.01) and PDR (P = 0.003) than in normal eyes. Conclusion: Total retinal blood flow was significantly lower in eyes with severe NPDR and PDR compared with normal eyes. Retinal blood flow determined by Doppler OCT may be a useful parameter for evaluating patients with DR.