Detection and quantitative measurement of variations in the retinal blood vessels can help diagnose several diseases including diabetic retinopathy. Intrinsic characteristics of abnormal retinal images make blood vessel detection difficult. The major problem with traditional vessel segmentation algorithms is producing false positive vessels in the presence of diabetic retinopathy lesions. To ov...

Retinal vessels identification and localization aim to separate the different retinal vasculature structure tissues, either wide or narrow ones, from the fundus image background and other retinal anatomical structures such as optic disc, macula, and abnormal lesions. Retinal vessels identification studies are attracting more and more attention in recent years due to non-invasive fundus imaging ...

a 41-year-old man was referred with a complaint of visual loss in his left eye and his best corrected visual acuity was 20/80. slit lamp examination showed arborizing conjunctival vessels and dry eye. fundus examination and fluorescein angiography revealed a non-ischemic central retinal vein occlusion. cardiovascular, rheumatologic, and hematologic work up showed no abnormal findings. an ascert...

Coats' disease is an idiopathic ophthalmic condition caused by a defect in the development of retinal vasculature, characterized by retinal telangiectasis, haemorrhages, intraretinal and subretinal exudation. There are two pathological processes, which are evident in Coats' disease. The first consists of a breakdown of the bloodretinal barrier at the endothelial level, which causes plasma leaka...

advances in optical coherence tomography have enabled a better appreciation of the role of pathologic choroidal changes in a variety of retinal disease. a “pachychoroid” (pachy-[prefix]: thick) is defined as an abnormal and permanent increase in choroidal thickness often showing dilated choroidal vessels and other structural alterations of the normal choroidal architecture. central serous c...

In several disease states, abnormal growth of blood vessels is associated with local neuronal degeneration. This is particularly true in ocular diseases such as retinal angiomatous proliferation (RAP) and macular telangiectasia (MacTel), in which, despite the absence of large-scale leakage or hemorrhage, abnormal neovascularization (NV) is associated with local neuronal dysfunction. We describe...

distribution of retinal blood vessels (rbvs) in retinal images has an important role in the prevention, diagnosis, monitoring and treatment of diseases, such as diabetes, high blood pressure, or heart disease. therefore, detection of the exact location of rbvs is very important for ophthalmologists. one of the frequently used techniques for extraction of these vessels is region growing-based se...

A 68-year-old woman presented with a visual field defect in her right eye. The fundus of her right eye showed multiple telangiectatic vessels, retinal hemorrhages, and subretinal exudates in the inferior peripheral retina. Nine months later, the subretinal exudates extended to the fovea despite treatment with laser photocoagulation. Cryotherapy was not possible at the time because of the poster...

IN a paper on" Certain abnormal conditions of the macular region usually classed as colobomata," which appeared in this journal in *March, 1927, an attempt was made to classify congenital defects in the neighbourhood of the posterior pole and to provide some diagnostic points by means of which a rough idea of the time of origin and the mechanism of production of the abnormality might be gained....

Retinal image analysis is becoming eminent as a nonintrusive diagnosis method in modern ophthalmology. This paper is mainly focused on the early diagnosis of diabetic retinopathy by analysing and detecting of vascular structures in retinal images. When small vessels in the retina have high level of glucose, it produces blur vision which eventually leads to blindness. Usually retinal images are ...