In this paper, an analysis of images of the retinal fundus by means of a combination of soft-computing techniques is carried out in order to extract from blood vessels their bifurcation and crossover points. These retinal features are unique for each individual and therefore they are useful for a successive process of personal identification. In particular, the implemented method is based on fo...

Visual memories of landmarks play a major role in guiding the habitual foraging routes of ants and bees, but how these memories engage visuo-motor control systems during guidance is poorly understood. We approach this problem through a study of image matching, a navigational strategy in which insects reach a familiar place by moving so that their current retinal image transforms to match a memo...

PURPOSE The purpose of this study is to determine the ability of single-value metrics of retinal image quality of the eye to predict visual performance as measured by high (HC) and low (LC) -contrast acuity at photopic (P) and mesopic (M) light levels in eyes with 20/17 and better visual acuity. METHODS Forty-nine normal subjects in good health ranging in age from 21.8 to 62.6 with 20/17 or b...

since the birth of multi–spectral imaging techniques, there has been a tendency to consider and process this new type of data as a set of parallel gray–scale images, instead of an ensemble of an n–d realization. although, even now, some researchers make the same assumption, it is proved that using vector geometries leads to better results. in this paper, first a method is proposed to extract th...

In this paper, we propose a method for retinal image matching that can be used in image matching for person identification or patient longitudinal study. Vascular invariant features are extracted from the retinal image and a feature vector is constructed for each of the vessel-segments in the retinal blood vessels. The feature vectors are represented in a tree structure with maintaining the ves...

Although computerized retinal image blood vessel segmentation has been extensively researched, there is still room for improvement in the quality of the segmented images. Since retinal image analysis is still widely used in the diagnosis of diabetic retinopathy, efficient and accurate image characterization techniques are required. Previous work has mainly focused on improving segmentation accu...

Retinal images are in use by ophthalmologists for the clinical analysis and diagnosis of different retinal diseases. The ocular disease known as Diabetic Retinopathy (DR) is a retinal disease that causes microvascular changes in the eye retina. Hard Exudates (HE) a retinal lesion can be seen as bright yellowish spots in colored fundus photograph and as bright white blobs in red free fundus imag...

Optical coherence tomography (OCT) is an emerging imaging modality that has been widely used in the field of biomedical imaging. In the recent past, it has found uses as a diagnostic tool in dermatology, cardiology, and ophthalmology. In this paper we focus on its applications in the field of ophthalmology and retinal imaging. OCT is able to non-invasively produce cross-sectional volumetric ima...

THERE are some features relative to the size of the retinal images in these two conditions which are of general interest, though they are rarely discussed. Axial Ametropia.-The " basic " (blurred) retinal image is smallest in hyperopia, intermediate in emmetropia, and largest in myopia. The size of a blurred retinal image is best taken from the points in the diffusion circles at the extremities...

We measured perceived motion smear when retinal image motion was created either by a physically moving object or by movement of the eyes or head. Consistent with previous reports, the extent of perceived motion smear during an eye or head movement is less than that produced by physical object motion when the eyes are stationary. Moreover, perceived smear is substantially smaller when the motion...