Fovea and optic disc detection in retinal images with visible lesions

Abstract

The work herein presented aims at improving the detection of the fovea and optic disk anatomical structures in color fundus photographs from patients with visible lesions. The detection algorithm consists of five steps: selection of an area in the image where the optic disk is located using Sobel operator, extraction of optic disk boundaries applying the Hough transform to detect center and diameter of optic disk, detection of the ROI (region of interest) where the fovea is located based on the optic disk center and its diameter, detection of the fovea within the ROI. The proposed improvement adds an additional mask based on an estimation of the vessels present so that lesions that lie away from the vessels do not influence the Sobel operator result. The developed algorithm has been tested in public datasets such as STARE and also on proprietary dataset with 1464 images (ground truth generated by experts). © 2012 IFIP International Federation for Information Processing.