Age related macular degeneration (AMD) is a complex multifactorial disease caused by the interplay of age and genetic and environmental risk factors. A common feature observed in early and both forms of late AMD is the breakdown of the physiologically immunosuppressive subretinal environment and the protracted accumulation of mononuclear phagocytes (MP). We here discuss the origin and nature of subretinal MPs, the mechanisms that lead to their accumulation, the inflammatory mediators they produce as well as the consequences of their chronic presence on photoreceptors, retinal pigment epithelium and choroid. Recent advances highlight how both genetic and environmental risk factors directly promote subretinal inflammation and tip the balance from a beneficial inflammation that helps control debris accumulation to detrimental chronic inflammation and destructive late AMD. Finally, we discuss how changes in life style or pharmacological intervention can help to break the vicious cycle of inflammation and degeneration, restore the immunosuppressive properties of the subretinal space, and reestablish homeostasis.
Contrary to Alzheimer's disease (AD), the APOE2 allele increases and the APOE4 allele reduces the risk to develop age-related macular degeneration (AMD) compared with the most common APOE3 allele. The underlying mechanism for this association with AMD and the reason for the puzzling difference with AD are unknown. We previously demonstrated that pathogenic subretinal mononuclear phagocytes (MPs) accumulate in Cx3cr1-deficient mice due to the overexpression of APOE, interleukin-6, and CC chemokine ligand 2 (CCL2). We here show using targeted replacement mice expressing the human APOE isoforms (TRE2, TRE3, and TRE4) that MPs of TRE2 mice express increased levels of APOE, interleukin-6, and CCL2 and develop subretinal MP accumulation, photoreceptor degeneration, and exaggerated choroidal neovascularization similar to AMD. Pharmacological inhibition of the cytokine induction inhibited the pathogenic subretinal inflammation. In the context of APOE-dependent subretinal inflammation in Cx3cr1 GFP/GFP mice, the APOE4 allele led to diminished APOE and CCL2 levels and protected Cx3cr1 GFP/GFP mice against harmful subretinal MP accumulation observed in Cx3cr1 GFP/GFP TRE3 mice. Our study shows that pathogenic subretinal inflammation is APOE isoform-dependent and provides the rationale for the previously unexplained implication of the APOE2 isoform as a risk factor and the APOE4 isoform as a protective factor in AMD pathogenesis.
We report a case of central retinal artery occlusion (CRAO) in a patient with a previous history of severe COVID-19 disease. This disease has been associated with inflammatory-induced homeostasis changes leading to endothelial dysfunction and a procoagulant state with multi-organ involvement, but the burden of thromboembolic complications in COVID-19 patients is currently unknown. The pathogenesis of retinal artery occlusions is a multifactorial process where inflammation and hypercoagulation state are established risk factors. Even if our experience may represent a coincidental relationship, it is likely that COVID-19 patients could be at risk of developing retinal vascular occlusions. A focused ophthalmological surveillance is advisable to prevent and manage this possible cause of severe vision loss that has an important impact in health care system.
Objectives: To review the frequency and nature of idiopathic macular telangiectasia and to classify the disorders based on new clinical and imaging observations. Methods: A combined retrospective and prospective analysis of newly diagnosed patients seen over a period of 3 years. Patients were identified based on the GassBlodi classification and were studied with biomicroscopy, fluorescein angiography, and optical coherence tomography.Results: Ten patients associated with aneurysmal telangiectasia (Gass-Blodi group 1) and 26 patients with perifoveal telangiectasia (Gass-Blodi group 2) were recruited. None with occlusive telangiectasia (Gass-Blodi group 3) were identified. New observations based on clinical, fluorescein angiographic, and optical coherence tomographic findings were made. Conclusions:Our series was similar to that in the GassBlodi study in terms of frequency. New observations in groups 1 and 2 have expanded our knowledge of the clinical spectrum of these disorders. A simplified classification termed idiopathic macular telangiectasia with 2 distinct types (type I, or aneurysmal telangiectasia, and type II, or perifoveal telangiectasia) was proposed to produce a better understanding of the entities and to enhance teaching and research. The third type, occlusive telangiectasia, has been omitted from our classification based on its rarity and presence of capillary nonperfusion rather than macular telangiectasia as the primary abnormality.
In this phase IIb clinical trial, a 62% relative benefit from baseline was noted in the E10030 1.5 mg combination therapy group compared with the anti-VEGF monotherapy group. A favorable safety and efficacy profile of E10030 combination therapy for nAMD was evident across multiple clinically relevant end points. This highly powered study provides strong rationale for a confirmatory phase III clinical trial.
Recent developments in vitreoretinal surgery have increased the need for suitable vitreous substitutes. A successful substitute should maintain all the physical and biochemical properties of the original vitreous, be easy to manipulate, and be long lasting. Substitutes can be gaseous or liquid, both of which have associated advantages and disadvantages related to their physical properties and use. Furthermore, new surgical techniques with smaller vitreoretinal instruments have driven the use of more viscous substitutes. In this review, we analyze and discuss the most frequently used vitreous substitutes and look ahead to future alternatives. We classify these compounds based on their composition and structure, discuss their clinical use with respect to their associated advantages and disadvantages, and analyze how new vitreoretinal surgical techniques have modified their use.
Study characteristics We included three studies, published between 1996 and 2004 and conducted in the USA and the UK, including 270 eyes in analyses, comparing vitrectomy and observation after 6 or 12 months. The evidence is current as of March 2015. Key results Vitrectomy improved visual acuity in participants with macular hole by about 1.5 lines of a standard distance acuity chart. Macular hole closure was much more likely with vitrectomy compared to observation, with mean closure rates of 76% versus 11%, respectively. Cataract surgery was common in operated eyes. In the largest study, retinal detachment occurred in the months following vitrectomy in about 5% of cases. Quality of the evidence The evidence was of moderate quality, as the visual acuity measurement was unmasked. ⊕⊕ low 1,3-4 Vitrectomy for idiopathic macular hole (Review)
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