Search results for "Retinal"
showing 10 items of 631 documents
Macular Structure–Function Relationships of All Retinal Layers in Primary Open-Angle Glaucoma Assessed by Microperimetry and 8 × 8 Posterior Pole Ana…
2021
Purpose: The aim of this study is too correlate the sensitivity and thickness values of intraretinal layers at macula in healthy eyes and primary open-angle glaucoma (POAG) eyes. Methods: The thickness of different intraretinal segmentations was estimated by means of optical coherence tomography (OCT) Spectralis (Heidelberg, Engineering, Inc., Heidelberg, Germany) with the posterior pole analysis program 8 × 8 in 91 eyes from 91 patients (60 with glaucoma and 31 healthy patients). Macular sensitivity was also measured with an MP-1 microperimeter (Nidek Instruments, Inc Padova, Italy) with a customized, 36-stimulus pattern adjusted to an anatomical correspondence with the OCT grid. Correlati…
Anatomical and functional macular changes after rhegmatogenous retinal detachment with macula off
2011
International audience; Purpose: To evaluate the correlation between morphologic changes in the outer retina and visual function after successful repair of rhegmatogenous retinal detachment with macula off. Methods: Thirty patients (30 eyes) with successful repair of rhegmatogenous retinal detachment (RD) after macula off and a minimum 6-month follow-up after the surgery were examined. Preoperative characteristics of the RD (visual acuity and duration) were collected. Postoperative visual acuity measurement with ETDRS scale and fundus autofluorescence (FAF) were performed. Spectral-Domain Optical Coherence Tomography (HRA OCT) of outer retina was performed to analyse the number of disrupted…
Is Saffron Able to Prevent the Dysregulation of Retinal Cytokines Induced by Ocular Hypertension in Mice?
2021
Cytokine- and chemokine-mediated signalling is involved in the neuroinflammatory process that leads to retinal ganglion cell (RGC) damage in glaucoma. Substances with anti-inflammatory properties could decrease these cytokines and chemokines and thus prevent RGC death. The authors of this study analysed the anti-inflammatory effect of a hydrophilic saffron extract standardized to 3% crocin content, focusing on the regulation of cytokine and chemokine production, in a mouse model of unilateral laser-induced ocular hypertension (OHT). We demonstrated that following saffron treatment, most of the concentration of proinflammatory cytokines (IL-1β, IFN-γ, TNF-α, and IL-17), anti-inflammatory cyt…
Plasmalogens and cell-cell communication between retinal glial cells
2016
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.; Purpose: Plasmalogens (or ether-lipids) are a particular class of glycerophospholipids characterized by the presence of a vinyl-ether bond at the sn-1 position of the glycerol backbone and by the preferential esterification of polyunsaturated fatty acids (PUFAs) at the sn-2 position. Plasmalogens are found at high concentrations in retinal macroglial cells such as Müller cells and astrocytes. Müller cells and astrocytes are known to communicate by the way of intracellular calcium waves and gap junctions. Connexin 43 is the major protein of these communicating junctions. The aim o…
Contributions à l'analyse et à l'interprétation des images : Extraction et représentation de caractéristiques
2016
Ce mémoire, rédigé en vue de l'obtention de l'Habilitation à Diriger des Recherches (HDR), offre un aperçu des travaux de recherche et d’encadrement que j’ai pu mener depuis l'obtention de mon doctorat. Il montre la diversité des champs d’application et de recherche (en vision et en imagerie médicale) que j’ai pu couvrir , ainsi que mon implication dans l’encadrement doctoral.Mes activités de recherche se divisent en deux grandes parties. D'une part, l'analyse de scènes dynamiques, à savoir la détection de regions d'intérêt dans des séquences d'images, pour réduire la taile des données à traiter, et la détection et le suivi d'objets mobiles à l'aide de caméras de diverses natures (perspecti…
Automated Detection of Microaneurysms Using Scale-Adapted Blob Analysis and Semi-Supervised Learning
2014
International audience; Despite several attempts, automated detection of microaneurysm (MA) from digital fundus images still remains to be an open issue. This is due to the subtle nature of MAs against the surrounding tissues. In this paper, the microaneurysm detection problem is modeled as finding interest regions or blobs from an image and an automatic local-scale selection technique is presented. Several scale-adapted region descriptors are then introduced to characterize these blob regions. A semi-supervised based learning approach, which requires few manually annotated learning examples, is also proposed to train a classifier to detect true MAs. The developed system is built using only…
The effect of blue-light-blocking lenses on retinal straylight
2021
Sometimes yellow-tinted lenses are recommended to help improve visual quality. As yellow lenses filter blue light, it is believed that their use could decrease the intensity of scattered light in the eye (retinal straylight). However, the results of some studies have contradicted this assumption (Van Os et al. 2017). Currently various nontinted blue-light-blocking lenses are used to protect the eyes from short-wavelength light. The objective of this study was to determine whether blue-light-blocking lenses affect the levels of retinal straylight in the eye. A straylight meter (C-Quant, Oculus) was used for retinal straylight measurements. The measurements were performed under four different…
Optical quality of hyperopic and myopic phakic intraocular lenses
2013
Aims: To assess and compare the optical quality of the myopic and hyperopic implantable collamer lens (ICL) from its wavefront aberrations for different powers and pupil diameters. Settings and Design: Prospective study. Material and Methods: The wavefront aberrations of two myopic (−3 and −6 diopters (D)) and two hyperopic V4b ICLs (+3 and +6D) were measured in vitro . To assess and compare the optical quality of different powers of ICLs, we analyzed the root mean square (RMS) of total higher order aberrations (HOAs), trefoil, coma, tetrafoil, secondary astigmatism, and spherical aberration at 3- and 4.5-mm pupil. In addition, the point spread functions (PSFs) of each ICL evaluated were ca…
Anatomic and functional follow-up of patients with an idiopathic epiretinal membrane and a preserved visual acuity
2013
Purpose: To determine the anatomic and functional retinal modifications in patients with an idiopathic epiretinal membrane (ERM) and a preserved visual acuity (VA).Methods: Monocentric, prospective study in 24 eyes of 24 patients with an ERM and a VA better than 20/25. Recorded data were best corrected VA on ETDRS scale, retinal anatomic lesions on spectral-domain OCT, retinal sensitivities on microperimetry and macular and foveal thicknesses at 0 and 6 months.Results: At inclusion, mean VA was 84 ± 5 letters, mean macular sensitivity was 14.0 ± 1.4 decibels (dB) and mean foveal sensitivity was 14,4 ± 1,5 dB. Mean macular thickness was 351 ± 34 µm and mean foveal thickness was 348 ± 66 µm. …