Search results for "Optic Disc"

Automated Detection of Optic Disc Location in Retinal Images

2008

This contribution presents an automated method to locate the optic disc in color fundus images. The method uses texture descriptors and a regression based method in order to determine the best circle that fits the optic disc. The best circle is chosen from a set of circles determined with an innovative method, not using the Hough transform as past approaches. An evaluation of the proposed method has been done using a database of 40 images. On this data set, our method achieved 95% success rate for the localization of the optic disc and 70% success rate for the identification of the optic disc contour (as a circle).

Paraneoplastic Focal Outer Retinitis and Optic Neuropathy in a Patient with Small Cell Lung Carcinoma and Anti-CRMP5, Anti-HU and Anti-Amphiphysin An…

2020

Our aim is to describe clinical and optical coherence tomographic features of acute paraneoplastic focal outer retinitis associated with optic neuropathy in a patient diagnosed with small cell lung carcinoma. Bilateral focal outer retinitis, bilateral optic disc oedema and vitritis were identified in a patient with progressive bilateral visual loss and ataxia. Spectral domain optical coherence tomography (SD-OCT) revealed various extents of granular hyperreflectivity and atrophy of the macular outer retinal layers. Serum and cerebrospinal fluid positivity for anti-CRMP5, anti-HU and anti-amphiphysin antibodies intensified the search for an underlying malignancy, and a small cell lung carcin…

Serous Detachment of the Retina: A Complication of Branch Retinal Vein Stenosis

2005

The author reports a case of serous detachment of the retina, which has developed in an eye with veno-venous collaterals, secondary to stenosis of a branch of the central retinal vein near the optic disc. This complication has not previously been described in this retinal vascular obstructive disease.

Human Visual Perception and Retinal Diseases

2010

Retinal diseases are causing alterations of the visual perception leading sometimes to blindness. For this reason, early detection and diagnosis of retinal pathologies is very important. Using digital image processing techniques, retinal images may be analyzed quickly and computer-assisted diagnosis systems may be developed in order to help the ophthalmologists to make a diagnosis. In this paper we described shortly two computer-assisted systems for the detection of retinal landmarks (optic disc and vasculature) together with a brief introduction to the human visual system and to some alterations of the visual perception caused by retinal diseases.

Optic disc positioning and blood vessels extraction on eye fundus

2009

This paper presents two methods aimed to the optic disc positioning on the retinal images. The first is based on a template of the entire image, while the second is based on the retinal vascularisation. For this second task, also a vessel extraction method is provided. Both the algorithm have been tested on test images of the Drive Database.

Peripapillary staphyloma associated with morning glory anomaly,

2006

We report a patient with concomitant occurrence of peripapillary staphyloma and morning glory anomaly. The morning glory anomaly presented with an optic nerve head with oblique entrance, located on one side of the peripapillary staphyloma, giving an unusually asymmetric and previously undescribed appearance to the abnormality. The optical coherence tomography provided useful information about the shape and deepness of the peripapillary staphyloma and disclosed a retinal detachment not appreciated ophthalmoscopically.

2021

Introduction Niemann-Pick type C (NPC) is a lysosomal storage disease that is progressive and life-limiting, with an estimated incidence of 1:120,000 live births. In addition to systemic manifestation with (hepato-)splenomegaly, there are a number of neurological manifestations (ataxia, dysarthria, dementia, cataplexy, epileptic seizures, and psychiatric disorders). Characteristic is vertical supranuclear gaze palsy, which is often overlooked. Early diagnosis and start of therapy improve quality of life. This study aimed to characterize oculomotor dysfunction of NPC patients, and to provide ophthalmologic data including retinal imaging. Methods Eighteen patients with biochemically or genet…

Variations of OCT measurements corrected for the magnification effect according to axial length and refractive error in children

2018

Purpose: The aim of this paper was to examine the distribution of macular, retinal nerve fiber layer (RNFL) thickness and optic disc parameters of myopic and hyperopic eyes in comparison with emmetropic control eyes and to investigate their variation according to axial length (AL) and spherical equivalent (SE) in healthy children. Methods: This study included 293 pairs of eyes of 293 children (145 boys and 148 girls), ranging in age from 6 to 17 years. Subjects were divided according to SE in control (emmetropia, 99 children), myopia (100 children) and hyperopia (94 children) groups and according to axial AL in 68 short ([Formula: see text]22.00[Formula: see text]mm, 68), medium (from [For…

Arteriovenöse Dissektion (AVD) bei retinalen Venolenastverschlüssen

2009

BACKGROUND: The aim of this study is to report on arteriovenous sheathotomy in branch retinal vein occlusion (BRVO) with a long-term follow-up and examine the visual field effects of this surgical approach. PATIENTS AND METHODS: In a clinical trial 36 eyes with branch retinal vein occlusion (22 eyes with ischaemia, 14 eyes with chronic macular oedema) underwent surgical decompression accompanied by peeling of the membrana limitans interna after prior isovolemic haemodilution for 3 months had been unsuccessfull. RESULTS: All eyes showed a significant reduction of macular oedema 3 months after surgery. During follow-up (median: 26.4 months) visual acuity increased in 24 / 36 eyes and was stab…

Übereinstimmung von klinischer Beurteilung, Heidelberg-Retina-Tomograph (HRT) und Nerve Fiber Analyzer (GDx) in der Glaukomdiagnostik

2004

BACKGROUND We have made a comparison of clinical evaluation, Heidelberg-Retina-Tomograph (HRT) and Nerve Fiber Analyzer (GDx) in diagnosing glaucoma. MATERIALS AND METHODS One eye of 38 glaucoma patients and 26 non-glaucoma patients was examined with HRT and GDx. Assignment of the patients into the two groups by clinical evaluation was performed on the basis of visual field and optic disc results. As classification criterion for glaucoma/non-glaucoma by means of the instruments we employed the statistical classification of the HRT and "the number" of the GDx. Statistical analysis was performed with Cohen's kappa and McNemar tests. Additionally, ROC curves for evaluation of the sensitivity a…