Proliferative diabetic retinopathy characterization based on the spatial organization of vascular junctions in fundus images

Proliferative diabetic retinopathy is an important public health issue with deteriorating impact on the vision of its patient. In this study, a novel approach is proposed for the characterization of abnormal vessels based on a spatial point pattern method. Points of interest corresponding to vascular junctions are detected by a perceptual organization technique, and then second-order statistical measures are computed. Significant differences (p<;0.05) between healthy retinal regions and areas with neovascularizations were obtained, which suggests that the second-order statistics could be used as a relevant feature to discriminate the abnormal from the normal vasculature. The relevance of the new measures was also evaluated with respect to an existing set of features using classification. The inclusion of a new second-order measure increases the characterization sensitivity against the already existing features from 75.76% to 84.85%.