Abstract
Purpose :
Diabetic retinopathy is one of the leading causes of blindness is United States. Early detection and treatment of the disease is the finite goal to prevent complications. Optical coherence tomography angiography (OCTa) has gain momentum to be widely used in clinic. This has allowed noninvasive study of microvasculature in retina and choroid. However, similar to OCT the interpretation is mainly descriptive. Our aim is to identify imaging biomarkers to predict the severity of the diabetic retinopathy based on OCTa.
Methods :
Fifty subjects diagnosed with diabetes mellitus, retinopathy and no macular edema were enrolled in a cross-sectional, observational study and all underwent a complete ophthalmic examination. Thirty healthy subjects underwent dilated eye exam as control group. Diabetic retinopathy scoring was performed in acodrance to Early Treatment Diabetic Retinopathy Study (ETDRS). Subjects were evaluated using OCT angiography (AngioVue) and angiography was performed using a 6X6mm High resolution pattern. The superficial foveal vasculature raw data was exported to ArcGIS, a Geographic Information System for the pattern analysis of OCTa. Three morphological characteristics of the retinal vasculature were measured using the spatial analysis tools of ArcGIS. These characteristics include the intensity, density and interruption of the vasculature (a representative analysis is attached as Picture 1). The one-way analysis of variance (ANOVA) was used for statistics.
Results :
Eight patients categorized as mild diabetic retinopathy (MR), 10 patients as moderate diabetic retinopathy(MOR), 23 patients as Severe Diabetic retinopathy (SR) and 9 patients with proliferative diabetic retinopathy (PDR). All three morphological measures were significantly different among groups (Intensity: F(4,71)=3.16, P=0.019; Density: F(4,71)=3.82, P=0.007; Interruption: F(4,71))=4.32, P=0.003). The post-hoc analysis using the LSD Method revealed a significant difference of means between intensity (P=0.026) and density (P=0.016) of SR and control subjects. Interestingly, all measurements (intensity, density, and interruption) in patients with PDR were significantly different with other groups (P<0.05). However, no significant differences were detected between normal patients and patients with MD.
Conclusions :
OCTa quantification may be used as a biomarker for progress of diabetic retinopathy.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.