C. Jayakumari , T. Santhanam , Retinal Blood Vessel Segmentation for Assessment of Diabetic Retinopathy Using a Two-Dimensional Model, Asian Journal of Information Technology, Volume 6,Issue 12, 2007, Pages 1205-1211, ISSN 1682-3915, ajit.2007.1205.1211, (https://makhillpublications.co/view-article.php?doi=ajit.2007.1205.1211) Abstract: Retinal blood vessels are very imperative structures in ophthalmologic images. Automated image processing has the immense potential to assist the physicians in the early detection of diabetes, by observing the changes in blood vessel patterns in the retina. This study details a novel vessel tracking algorithm as a part of the set of tools exercised for the automated diagnosis of diabetic retinopathy. To begin with, the papilla is detected by utilizing Canny’s edge detection algorithm. Then, the blood vessels are traced by using the second-order derivative Gaussian filter. The projected algorithm has achieved acceptable results to spot the small veins/thin vessels that play a mighty contribution in the clinical arena. Keywords: Vessel extraction;vessel tracing;gaussian second derivate;two-dimensional model;segmentation