Search results for " retina"

El asesoramiento genético en los déficits visuales y auditivos

2008

espanolObjetivo: Las enfermedades hereditarias que afectan a la retina y la audicion presentan una amplia heterogeneidad clinica y genetica. Durante la pasada decada se han producido importantes avances en el conocimiento de la patogenia molecular de estas enfermedades y, actualmente, mas de 200 genes y loci estan implicados en enfermedades de la retina y mas de 60 son responsables de perdida de audicion. Metodo: El estudio genetico molecular es crucial para confirmar el diagnostico clinico, permite, en ocasiones, conocer el pronostico de la enfermedad, un consejo genetico y reproductivo adecuado y permite la posibilidad de crear grupos de pacientes geneticamente homogeneos para futuros ens…

Automatic Extraction of Blood Vessels, Bifurcations and End Points in the Retinal Vascular Tree

2008

In this paper we present an effective algorithm for automated extraction of the vascular tree in retinal images, including bifurcations, crossovers and end-points detection. Correct identification of these features in the ocular fundus helps the diagnosis of important systematic diseases, such as diabetes and hypertension. The pre-processing consists in artefacts removal based on anisotropic diffusion filter. Then a matched filter is applied to enhance blood vessels. The filter uses a full adaptive kernel because each vessel has a proper orientation and thickness. The kernel of the filter needs to be rotated for all possible directions. As a consequence, a suitable kernel has been designed …

Distacco di retina regmatogeno primario ed opacità corneali.

2008

FABC: Retinal Vessel Segmentation Using AdaBoost

2010

This paper presents a method for automated vessel segmentation in retinal images. For each pixel in the field of view of the image, a 41-D feature vector is constructed, encoding information on the local intensity structure, spatial properties, and geometry at multiple scales. An AdaBoost classifier is trained on 789 914 gold standard examples of vessel and nonvessel pixels, then used for classifying previously unseen images. The algorithm was tested on the public digital retinal images for vessel extraction (DRIVE) set, frequently used in the literature and consisting of 40 manually labeled images with gold standard. Results were compared experimentally with those of eight algorithms as we…

Q fever: a new ocular manifestation

2011

P Udaondo1,3, S Garcia-Delpech1,2, D Salom1,2, M Garcia-Pous1, M Diaz-Llopis1,21Department of Ophthalmology, Nuevo Hospital Universitario y Politecnico La Fe, Valencia, Spain; 2Faculty of Medicine, Universitat de València, Valencia, Spain; 3Universidad Cardenal Herrera CEU, Valencia, SpainAbstract: Q Fever is a zoonosis caused by Coxiella burnetii. Ocular manifestations are rare in this infection. We describe the case of a man complaining of an intense retro-orbital headache, fever, arthralgia, and bilateral loss of vision, who showed an anterior uveitis accompanied by exudative bilateral inferior retinal detachment and optic disk edema. At the beginning, a Vogt–Koyanag…

Tilted discs and central retinal vein occlusion.

1993

Laser polarimetrie mit variablem Abgiech der Kornea (GDx VCC) zur Messung der retinalen Nervenfaserschicht bei primaren akuten Winkelblockglaukom

2008

Liposomally-entrapped ganciclovir for the treatment of cytomegalovirus retinitis in AIDS patients

1992

Treatment of retinitis by cytomegalovirus (CMV) in AIDS patients requires frequent repetitive injections of intravitreal ganciclovir (GCV). This study was undertaken to establish experimentally whether the intravitreal application of liposomally-entrapped GCV could prolong intraocular therapeutic levels when compared with the intravitreal injection of free GCV, and the clinical effectiveness of this approach in AIDS patients. Intraocular concentration of GCV was determined by means of an ELISA test in rabbit vitreous 2, 3, 7, and 14 days after a single intravitreal injection of either different doses of the free drug (0.2-20 mg) or 1 mg of liposomally-entrapped GCV. After 72 h, only the vit…

Deletion of myosin VI causes slow retinal optic neuropathy and age-related macular degeneration (AMD)-relevant retinal phenotype

2015

The unconventional myosin VI, a member of the actin-based motor protein family of myosins, is expressed in the retina. Its deletion was previously shown to reduce amplitudes of the a- and b-waves of the electroretinogram. Analyzing wild-type and myosin VI-deficient Snell’s Waltzer mice in more detail, the expression pattern of myosin VI in retinal pigment epithelium, outer limiting membrane, and outer plexiform layer could be linked with differential progressing ocular deficits. These encompassed reduced a-waves and b-waves and disturbed oscillatory potentials in the electroretinogram, photoreceptor cell death, retinal microglia infiltration, and formation of basal laminar deposits. A pheno…

Indocyanine green in congenital hypertrophy of the retinal pigment epithelium

2005

To report a case of congenital hypertrophy of the retinal pigment epithelium followed up for 7 years showing features not previously reported. A complete fundus examination including fluorescein angiography was performed at first examination and at follow-up. The area of congenital hypertrophy of the retinal pigment epithelium presented morphologic changes, showing enlargement of the lesion on one side associated with partial regression on another side. In addition, the indocyanine green angiography findings revealed that this test was more useful than fluorescein angiography to delineate the real boundaries of the lesion and disclosed hypofluorescent areas inside the main lesion that were …