Retina images are obtained from the fundus camera and graded by skilled professionals. However there is considerable shortage of expert observers has encouraged computer assisted monitoring. Evaluation of blood vessels network plays an important task in a variety of medical diagnosis. Manifestations of numerous vascular disorders, such as diabetic retinopathy, depend on detection of the blood v...

The change in morphology, diameter, branching pattern or tortuosity of retinal blood vessels is an important indicator of various clinical disorders of the eye and the body. This paper reports an automated method for segmentation of blood vessels in retinal images. A unique combination of techniques for vessel centerlines detection and morphological bit plane slicing is presented to extract the...

Changes in retinal blood vessel features are precursors of serious diseases such as cardiovascular disease and stroke. Therefore, analysis of retinal vascular features can assist in detecting these changes and allow the patient to take action while the disease is still in its early stages. Automation of this process would help to reduce the cost associated with trained graders and remove the is...

Viper venoms act mainly on blood and blood vessels. Reports of ophthalmic manifestations after snakebite include ptosis and ophthalmoplegia. In the current study, we describe a case that developed bilateral retinal and subretinal hemorrhage following snakebite. Bilateral retinal hemorrhage is a rare ocular complication of snake envenomation and has not been reported with fundus photographs in t...

PURPOSE Aberrant growth of blood vessels in the eye is a major cause of vision loss, occurring as a complication of diabetic retinopathy, age-related macular degeneration, and retinal vascular occlusions, among others. Whereas in humans, in vivo angiography is routinely used to image such diseases, many animal models of ocular vascular disease and development rely on dissected tissues that may ...

PURPOSE To present a novel automated method for tracking and detection of retinal blood vessels in fundus images. METHODS For every pixel in retinal images, a feature vector was computed utilizing multiscale analysis based on Gabor filters. To classify the pixels based on their extracted features as vascular or non-vascular, various classifiers including Quadratic Gaussian (QG), K-Nearest Nei...

Abnormalities of retinal vasculatures can indicate health conditions in the body, such as the high blood pressure and diabetes. Providing automatically determined width ratio of arteries and veins (A/V ratio) on retinal fundus images may help physicians in the diagnosis of hypertensive retinopathy, which may cause blindness. The purpose of this study was to detect major retinal vessels and clas...

PURPOSE To assess the role of astrocytes in controlling the growth of developing retinal vessels. METHODS Growth of retinal vessels in the neonatal rat retina was examined in three conditions: normal development, cyclic hyperoxia, and normoxia (1 day 70% to 75% oxygen, 1 day room air for up to seven cycles from birth, and room air for up to 16 days), and direct hypoxia (10% oxygen from postna...

The blood-retinal barrier is part of the blood-ocular barrier. Retinal pigment epithelial cells connected by tight junctions serve as an outer blood-retinal barrier, and the nonfenestrated endothelial cells of blood vessels sealed by tight junctions serve as an inner blood-retinal barrier. Using antibodies specific for the erythrocyte/HepG2-type glucose transporter (GLUTl), one isoform of facil...