Peripapillary Region Perfusion and Retinal Nerve Fiber Layer Thickness Abnormalities in Diabetic Retinopathy Assessed by OCT Angiography

PURPOSE: To quantify peripapillary region perfusion and retinal nerve fiber layer (RNFL) thickness abnormalities in different stages of diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA). METHODS: Seventy-two eyes of 72 patients with diabetes were included as follows: 23 with no DR (No DR), 24 with mild-to-moderate nonproliferative DR (mild DR), 25 with severe nonproliferative to proliferative DR (severe DR), and 26 age-matched healthy controls. All eyes underwent a 4.5 × 4.5-mm rectangle scan centered on the optic nerve head. Vessel densities and RNFL thickness for the peripapillary area were calculated. RESULTS: A statistically significant decrease in vessel density was found in the peripapillary region with increased DR severity (all P < 0.001). There were significant correlations between DR severity and vessel density in the peripapillary region (P < 0.001), but not between DR severity and RNFL thickness (P > 0.05). There was a significantly positive correlation between vessel density and RNFL thickness of the peripapillary region in the mild DR group (r = 0.726, P < 0.001) but not in the no DR group (r = 0.008, P = 0.973) or the severe DR group (r = 0.281, P = 0.173). CONCLUSIONS: Vessel density in the peripapillary region correlated significantly with DR severity, decreasing with DR aggravation. There was no obvious correlation observed between RNFL thickness and DR severity. TRANSLATIONAL RELEVANCE: Vessel density in the peripapillary region, assessed by OCTA technology, can be potentially useful for analyzing and monitoring retinal nerve changes in DR patients.