Search results for " RETINA"

A multimodal retina-iris biometric system using the Levenshtein distance for spatial feature comparison

2020

Abstract The recent developments of information technologies, and the consequent need for access to distributed services and resources, require robust and reliable authentication systems. Biometric systems can guarantee high levels of security and multimodal techniques, which combine two or more biometric traits, warranting constraints that are more stringent during the access phases. This work proposes a novel multimodal biometric system based on iris and retina combination in the spatial domain. The proposed solution follows the alignment and recognition approach commonly adopted in computational linguistics and bioinformatics; in particular, features are extracted separately for iris and…

Decreasing dietary linoleic acid promotes long chain omega-3 fatty acid incorporation into rat retina and modifies gene expression

2011

International audience; Age-related macular degeneration (AMD) may be partially prevented by dietary habits privileging the consumption of ω3 long chain polyunsaturated fatty acids (ω3s) while lowering linoleic acid (LA) intake. The present study aimed to document whether following these epidemiological guidelines would enrich the neurosensory retina and RPE with ω3s and modulate gene expression in the neurosensory retina. Rat progenitors and pups were fed with diets containing low or high LA, and low or high ω3s. After scotopic single flash and 8-Hz-Flicker electroretinography, rat pups were euthanized at adulthood. The fatty acid profile of the neurosensory retina, RPE, liver, adipose tis…

Genome-wide meta-analyses of multiancestry cohorts identify multiple new susceptibility loci for refractive error and myopia

2013

Author version made available in accordance with the publisher's policy.

Delayed filling of retinal and ciliary circulation after central retinal artery occlusion

1988

The filling times of the retinal and choroidal circulation were evaluated in 17 patients with central retinal artery occlusion by means of fluorescein angiography. A correlation between the filling times of the two circulations was found. However, two filling patterns were seen: first, both fillings delayed; second, both fillings normal. It is probable that in the former case an obstructive disease of the carotid arteries exists, while in the latter case an important pathology of the carotid arteries is lacking, favouring a rapid restoration of the retinal circulation. This hypothesis seems to be confirmed by the results of the Doppler velocimetry of the carotid arteries.

Ophthalmologic Imaging Methods

2005

Color Doppler ultrasonography of the eye and orbit

1993

Color Doppler imaging is the recent development in ultrasonography that allows simultaneous two-dimensional structural imaging in Doppler evaluation of blood flow. With this technique, it is possible for the first time to indirectly display the fine orbital vessels such as the ophthalmic artery and its branches, the central retinal artery, the posterior ciliary artery, and the lacrimal artery. Also, the display of venous structures such as the superior ophthalmic vein, the vortex vein, and the central retinal vein is possible. In addition to the qualitative display of those vessels, the hemodynamics in those vessels can be quantitatively assessed by looking at the Doppler spectrum and deter…

Ozone Therapy as treatment for severe cases without good evolution in ophthalmology [abstract]

2019

PURPOSE: In ophthalmology many diseases lead to irreversible blindness, something that implies millions of dollars in care because people with these difficulties loose their autonomy, becoming dependent in all their everyday activities.
 This presentation will focus on clinical cases of the following pathologies treated with Ozone Therapy because all these were already being treated in a conventional way without signs of improvement. They are primary open-angle glaucoma, age-related macular degeneration, diabetic retinopathy, occlusion of the central retinal artery, facial paralysis and herpetic polyneuropathy associated with orbital apex syndrome.
 
 CASE PRESENTATION: As an…

Apprehending ganglioside diversity: a comprehensive methodological approach

2015

Gangliosides make a wide family of glycosphingolipids ubiquitously expressed in mammalian tissues and particularly abundant in the brain and nervous system. They exhibit a huge diversity due to structural variations in both their oligosaccharidic chain and ceramide moiety, which represent a real analytical challenge. Since their discovery in the 1940s, methods have persistently improved until the emergence of Liquid Chromatography/Mass Spectrometry (LC/MS) which offers a high level of specificity and sensitivity and is suitable with high-throughput profiling studies. We describe here a comprehensive approach relying on various techniques and aiming at fully characterizing gangliosides in bi…

Purification of a fetal bovine serum factor that inhibits DNA synthesis in chick embryo retinas

1992

Exudates as Landmarks Identified through FCM Clustering in Retinal Images

2020

The aim of this work was to develop a method for the automatic identification of exudates, using an unsupervised clustering approach. The ability to classify each pixel as belonging to an eventual exudate, as a warning of disease, allows for the tracking of a patient&rsquo