Retina Segmentation to Obtain the Optic Nerve Area and Blood Vessels

This paper proposes a new approach for the segmentation of the retina images to obtain the optic nerve and blood vessels regions. We used retinal images from DRIVE and STARE databases which include different situations like illumination variations, different optic nerve positions (left, right and center). Illumination problem has been solved by preprocessing stage including image histogram- based illumination correction. Next, some morphological operations were used to filter the preprocessed image to obtain the ROI region, then, the center and radius of optic nerve were determined, and the optic nerve region was extracted from the original image. In blood vessels segmentation, we applied the illumination correction and median filtering.Then the closing, subtraction and morphological operations were done to get the blood vessels image which was thresholded and thinned to get the final blood vessels image. At optic nerve segmentation, the study shows that 40 of 50 retinal images from STARE database were segmented correctly, and 84 of 100 from DRIVE database were extracted correctly which result in 82.66% segmentation rate, while the blood vessels were segmented correctly from all database images. The current study was compared with others at the same region.