Search results for "Retina"
showing 10 items of 864 documents
Risk of Death Associated With Intravitreal Anti-Vascular Endothelial Growth Factor Therapy: A Systematic Review and Meta-analysis.
2020
Importance Although intravitreal anti–vascular endothelial growth factor (VEGF) treatment represents the first-line therapy for many retinal diseases, the issue of their systemic safety is debatable. Objectives To assess whether intravitreal anti-VEGF therapy might be associated with increased risk of mortality and which variables are associated with the increase. Data Sources PubMed, MEDLINE, and Embase databases, the Cochrane Library, and ClinicalTrials.gov were systematically searched from inception to May 6, 2019. Study Selection Randomized clinical trials comparing intravitreal anti-VEGF treatment with control groups and with follow-up of at least 6 months were selected. Data Extractio…
Treat and extend versus fixed regimen in neovascular age related macular degeneration: A systematic review and meta-analysis
2020
Purpose: To compare efficacy of treat and extend (T&E) versus fixed regimen treatment protocols in neovascular age-related macular degeneration (nAMD). Methods: Randomized clinical trials (RCTs) comparing T&E versus fixed regimen protocols for nAMD were systematically searched. Primary outcome was to compare the mean best corrected visual acuity (BCVA) change in T&E regimen versus fixed regimen. Secondary outcomes were change in the mean optical coherence tomography (OCT) central retinal thickness (CRT) and mean number of injections. Standardized mean difference (SMD) along with 95% confidence intervals (CIs) were calculated. Random-effect models were used for meta-analyses. Res…
Early OCTA Changes of Type 3 Macular Neovascularization Following Brolucizumab Intravitreal Injections
2022
Background and Objectives: Brolucizumab is a novel anti-vascular endothelial growth factor (VEGF), whose efficacy has been shown in the Hawk and Harrier phase 3 clinical studies. The goal of the present case series is to report initial results of brolucizumab intravitreal injections (IVI) on type 3 neovascularization in neovascular age-related macular degeneration (nAMD), evaluated by optical coherence tomography angiography (OCTA). Materials and Methods: This is a bicentric retrospective case series. Patients with newly diagnosed type 3 MNV treated with brolucizumab IVI and at least 6 months follow-up were enrolled. OCTA en face images and B-scans were analyzed for lesions at baseline, 1 m…
Changes in visual function and retinal structure in the progression of Alzheimer's disease
2019
Background Alzheimer's Disease (AD) can cause degeneration in the retina and optic nerve either directly, as a result of amyloid beta deposits, or secondarily, as a result of the degradation of the visual cortex. These effects raise the possibility that tracking ophthalmologic changes in the retina can be used to assess neurodegeneration in AD. This study aimed to detect retinal changes and associated functional changes in three groups of patients consisting of AD patients with mild disease, AD patients with moderate disease and healthy controls by using non-invasive psychophysical ophthalmological tests and optical coherence tomography (OCT). Methods We included 39 patients with mild AD, 2…
Effect of Light Scattering Simulation in the Eye on Different Color Stimuli Perception
2008
One of the factors which influences visual functions is intraocular light scattering. To assess the effect of light scattering and stimulus color on visual functions, visual acuity and retinal straylight were measured with and without light scattering occluder. For visual acuity measurements black Landolt optotypes on red, green and blue background were used. Retinal straylight was measured with a direct compensation method using the same colors stimuli. For one subject straylight was measured with 5 different light scattering levels of eye occluder.
[37] Interactions between vitamin A and vitamin E in liposomes and in biological contexts
1999
Publisher Summary This chapter discusses the interactions between vitamin A and vitamin E in liposomes. The chapter reviews several studies carried out by incorporating a variable proportion of all- trans -retinol and α-tocopherol in soybean phosphatidylcholine liposomes. It discusses the antioxidant effectiveness of all- trans - retinol in retinal membranes, whether deprived of endogenous α-tocopherol. In the experiments discussed in the chapter, synergistic effects between all- trans -retinal and α -tocopherol are evident in chemical bilayer as well as in natural membranes. In addition, when all- trans -retinol and α –tocopherol are allowed to act in combination, consumption of both antio…
Comparative assessment of the toxicology of vitamin A and retinoids in man.
1989
As the title implies, any assessment of the toxic effects of vitamin A derivatives must distinguish between vitamin A in the truest sense, i.e. retinol, and retinoic acid and its synthetic derivatives. Just as no single description is universally applicable to the mode of action of vitamin A derivatives, so too do their toxic effects defy generalization. The recommendation made in 1982 by IUPAC [Eur. J. Biochem., 129 (1989) 1] to designate all derivatives with the typical structure of the vitamin as being retinoids may be chemically logical and correct but, when it comes to describing the effects and side-effects of vitamin A derivatives, it leads to misunderstandings. Retinol, which is fre…
Classification of diabetes-related retinal diseases using a deep learning approach in optical coherence tomography
2019
Background and objectives: Spectral Domain Optical Coherence Tomography (SD-OCT) is a volumetric imaging technique that allows measuring patterns between layers such as small amounts of fluid. Since 2012, automatic medical image analysis performance has steadily increased through the use of deep learning models that automatically learn relevant features for specific tasks, instead of designing visual features manually. Nevertheless, providing insights and interpretation of the predictions made by the model is still a challenge. This paper describes a deep learning model able to detect medically interpretable information in relevant images from a volume to classify diabetes-related retinal d…
Pattern Dystrophy of the Macula in a Case of Steinert Disease
2013
<b><i>Introduction:</i></b> Myotonic dystrophies are typically associated with ocular complications like ptosis, weakness of the ocular muscle and cataracts, but also with less recognized retinal changes. <b><i>Case Report:</i></b> A 41-year-old female with type 1 myotonic dystrophy complained of progressive vision loss. Slit lamp examination revealed the presence of typical bilateral polychromatic cataract with posterior subcapsular component. Dilated fundus examination was remarkable for bilateral macular depigmented changes. Multimodal imaging analysis of the macula suggested the presence of a butterfly-shaped pattern dystrophy. <b>&l…
Xanthine oxidase catalyzes the oxidation of retinol.
2007
In mammals, xanthine oxidase (E.C. 1.17.3.2) catalyzes the hydroxylation of a wide variety of heterocyclic substrates such as purines, pyrimidines, and pterins, in addition to aldehydes [1] as all-trans-retinaldehyde [2-5]. Here, we show that buttermilk xanthine oxidase was capable to oxidizing all-trans-retinol (t-ROL) to all-trans-retinaldehyde (t-RAL) that was successively oxidized to all-trans-retinoic acid (t-RA). A rise in the enzyme activity, when t-ROL-CRBP complex was assayed, with respect to the free t-ROL, was observed. Furthermore, treatment of the enzyme with Na2S and glutathione resulted in a significant increment in catalytic activity toward t-ROL and t-RAL, due to the recons…