A supervised method is proposed for automated segmentation of vessels in fundus images of retina. This method is used to detect the retinal diseases by extracting the retinal vasculature utilizing 9-D feature vector based on orientation analysis of gradient vector field, morphological transformation, line strength measures, and Gabor filter responses. The feature vector encodes information to h...

In recent days glaucoma related problems are tremendously increased in a stratergical manner. Hence it is to be considered as a serious threat in biomedical problem among human beings. proper arrangement of retinal vessel provides information about the retinal abnormalities. This process help to find cause several retinal diseases. The assessment of blood vessel is used to find eye diseases suc...

These two statements, to which we shall refer as Statement 1 and Statement 2, while seemingly contradictory, are each partly true, though neither is complete. The first says that accommodation increases the size of the retinal image, that is it makes the image " larger ", but larger than what? The second says that in accommodation the retinal image is decreased in size, that is the image become...

Retinal vasculature is a network of vessels in the retinal layer. In ophthalmology, information of retinal vasculature in analyzing fundus images is important for early detection of diseases related to the retina, e.g. diabetic retinopathy. However, in fundus images the contrast between retinal vasculature and the background is very low. As a result, analyzing or visualizing tiny retinal vascul...

Introduction: contrast sensitivity is one of the most important psychophysical tests that may be used for the evaluation of refractive state of eye and retinal image quality. Yellow vs. blue color contrast sensitivity may be more suitable in this regard. Materials and Methods: thirty myopic eyes were considered in this study. Yellow vs. blue color contrast sensitivity was evaluated under the sa...

Evidence is presented supporting the idea that the human visual system has several specific sensitivities to different kinds of relative motion. These specific sensitivities include: sensitivity to a velocity difference between two different points A and B on one eye's retinal image, the two velocities being directed along the line AB; sensitivity to the velocity difference at A and B between v...