Abstract
Purpose: To compare vessel density in macular and peripapillary area between control subjects and patients with non-proliferative diabetic retinopathy (NPDR) using optical coherence tomography angiography (OCTA) and to evaluate the association between RNFL thickness and different stage of diabetic retinopathy.
Methods: A total of 170 eyes (normal control, 43; mild NPDR, 43; moderate NPDR, 42; severe NPDR, 42) underwent OCTA imaging. Optical coherence tomography angiographic parameters were vessel densities in superficial capillary plexus (SCP), deep capillary plexus (DCP) in macular area and peripapillary area.
Results: The reduction of vessel density of SCP and DCP in macular area, peripapillary area as well as RNFL thickness were correlated with increasing severity of DR. Vessel density of SCP and DCP in macular area, peripapillary area and FD300 in NPDR groups decreased as compared to normal control (P<0.001). Vessel density of DCP shows better ability to identify the severity of DR (sensitivity, and specificity of 88.1%, and 85.2%, respectively) than in FD 300, vessel density of SCP in macular area and peripapillary area
Conclusion: Macular and peripapillary vessel density as well as RNFL thickness were significantly decreased in different stage of NPDR compared to normal controls. Vessel density in DCP could be an objective and sensitive indicator for monitoring progression of DR. OCTA might be clinically useful to evaluate microvascular and microstructural alterations in macula and ONH, thus providing a new method to study the course of DR.
Key Words: Diabetic retinopathy, optical coherence tomography angiography, vessel density, RNFL thickness, FD 300