PURPOSE To investigate the nature and origin of the vitreous membranes in mice with knock-out of the Norrie gene product (ND mice). METHODS Eighty-two eyes of ND mice of different age groups (postnatal day [P]0-13 months) and 95 age-matched wild-type control mice were investigated. In vitreoretinal wholemounts and in sagittal sections, vessels and free cells were visualized by labeling for le...

In this paper, we present an automated method to segment blood vessels in fundus retinal images. The method could be used to support a non-intrusive diagnosis in modern ophthalmology for early detection of retinal diseases, treatment evaluation or clinical study. Our method combines the bias correction to correct the intensity inhomogeneity of the retinal image, and a matched filter to enhance ...

In cases with persistent primary vitreous in full-term infants there were vitreoretinal reactions including vitreoretinal anastomoses of blood vessels, vitreoretinal strands, traction folds of the retina, avascular retinal areas, hypoplasia of retinal blood vessels, rarefaction of retinal ganglion cells, and ischaemic structural changes of the retina. New vessel formation on the surface of avas...

In many diseases with a cardiovascular component, the geometry of microvascular blood vessels changes. These changes are specific to arteries and veins, and can be studied in the microvasculature of the retina using retinal photography. To facilitate large-scale studies of artery/vein-specific changes in the retinal vasculature, automated classification of the vessels is required. Here we prese...

Blood vessel segmentation from the retinal images is extremely important for assessing retinal abnormalities. A good amount of research has been reported on blood vessel segmentation, but significant improvement is still a necessity particularly on minor vessel segmentation. As the local contrast of blood vessels is unstable (intensity variation), especially in unhealthy retinal images, it beco...

Retinal vessels are the only blood vessels that can be viewed directly, in vivo, repetitively and non-invasively. Retinal vessel caliber is influenced by physiological (age, sex, race, blood pressure, blood glucose, body mass index) and pathological (atherosclerosis, dyslipidemia, smoking) determinants. There are studies on large population groups that demonstrate the associations between retin...

Recently, automated segmentation of retinal vessels in optic fundus images has been an important focus of much research. In this paper, we propose a multi-scale method to segment retinal vessels based on a weighted two-dimensional (2D) medialness function. The results of the medialness function are first multiplied by the eigenvalues of the Hessian matrix. Next, centerlines of vessels are extra...

MICHAELSON (1954), writing on the retinal blood vessels in man, stated that "an artery crossing an artery, or a vein crossing a vein, has not once been reported, or been personally observed". This is in keeping with the present hypothesis that the development of retinal vessels in vertebrates is stimulated by a local intraretinal factor. In man, each quadrant of the fundus accumulates, during d...

Purpose. To characterize developing retinal blood vessels with vascular markers and to relate the histochemical profile of maturing vessels to morphologic stages in retinal vascular development. Methods. Vessels were examined in frozen and paraffin-embedded retinas and in wholemounts of Macaca monkeys ranging in age from fetal day 75 (F75) to adulthood. Endothelial cells were visualized immunoh...