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We rely on vision more than on any other sense to obtain information about our environment. Hence, the loss or even impairment of vision profoundly affects our quality of life. Diet or food components have already demonstrated beneficial effects on the development of retinal diseases. Recently, there has been a growing interest in resources from marine animals and plants for the prevention of retinal diseases through nutrition. Especially fish intake and omega-3 fatty acids have already led to promising results, including associations with a reduced incidence of retinal diseases. However, the underlying molecular mechanisms are insufficiently explained. The aim of this review was to summarize the known mechanistic effects of marine resources on the pathophysiological processes in retinal diseases. We performed a systematic literature review following the PRISMA guidelines and identified 107 studies investigating marine resources in the context of retinal diseases. Of these, 46 studies described the underlying mechanisms including anti-inflammatory, antioxidant, antiangiogenic/vasoprotective, cytoprotective, metabolic, and retinal function effects, which we critically summarize. We further discuss perspectives on the use of marine resources for human nutrition to prevent retinal diseases with a particular focus on regulatory aspects, health claims, safety, and bioavailability. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration (AMD) is a multifactorial disease, which can culminate in irreversible vision loss and blindness in elderly. Nowadays, there is a big gap between dry AMD and wet AMD on treatment. Accounting for nearly 90% of AMD, dry AMD still lacks effective treatment. Numerous genetic and molecular researches have confirmed the significant role of the complement system in the pathogenesis of AMD, leading to a deeper exploration of complement inhibitors in the treatment of AMD. To date, at least 14 different complement inhibitors have been or are being explored in AMD in almost 40 clinical trials. While most complement inhibitors fail to treat AMD successfully, two of them are effective in inhibiting the rate of GA progression in phase II clinical trials, and both of them successfully entered phase III trials. Furthermore, recently emerging complement gene therapy and combination therapy also offer new opportunities to treat AMD in the future. In this review, we aim to introduce genetic and molecular associations between the complement system and AMD, provide the updated progress in complement inhibitors in AMD on clinical trials, and discuss the challenges and prospects of complement therapeutic strategies in AMD. [ABSTRACT FROM AUTHOR]

Retinal prostheses aim to improve visual perception in patients blinded by photoreceptor degeneration. However, shape and letter perception with these devices is currently limited due to low spatial resolution. Previous research has shown the retinal ganglion cell (RGC) spatial activity and phosphene shapes can vary due to the complexity of retina structure and electrode-retina interactions. Visual percepts elicited by single electrodes differ in size and shapes for different electrodes within the same subject, resulting in interference between phosphenes and an unclear image. Prior work has shown that better patient outcomes correlate with spatially separate phosphenes. In this study we use calcium imaging, in vitro retina, neural networks (NN), and an optimization algorithm to demonstrate a method to iteratively search for optimal stimulation parameters that create focal RGC activation. Our findings indicate that we can converge to stimulation parameters that result in focal RGC activation by sampling less than 1/3 of the parameter space. A similar process implemented clinically can reduce time required for optimizing implant operation and enable personalized fitting of retinal prostheses. [ABSTRACT FROM AUTHOR]

The Montreal Protocol has limited increases in the UV-B (280–315 nm) radiation reaching the Earth's surface as a result of depletion of stratospheric ozone. Nevertheless, the incidence of skin cancers continues to increase in most light-skinned populations, probably due mainly to risky sun exposure behaviour. In locations with strong sun protection programs of long duration, incidence is now reducing in younger age groups. Changes in the epidemiology of UV-induced eye diseases are less clear, due to a lack of data. Exposure to UV radiation plays a role in the development of cataracts, pterygium and possibly age-related macular degeneration; these are major causes of visual impairment world-wide. Photodermatoses and phototoxic reactions to drugs are not uncommon; management of the latter includes recognition of the risks by the prescribing physician. Exposure to UV radiation has benefits for health through the production of vitamin D in the skin and modulation of immune function. The latter has benefits for skin diseases such as psoriasis and possibly for systemic autoimmune diseases such as multiple sclerosis. The health risks of sun exposure can be mitigated through appropriate sun protection, such as clothing with both good UV-blocking characteristics and adequate skin coverage, sunglasses, shade, and sunscreen. New sunscreen preparations provide protection against a broader spectrum of solar radiation, but it is not clear that this has benefits for health. Gaps in knowledge make it difficult to derive evidence-based sun protection advice that balances the risks and benefits of sun exposure. [ABSTRACT FROM AUTHOR]

Objectives. The aim of this study is to evaluate longitudinal RNFL thickness changes in patients with open-angle glaucoma (OAG) who underwent pars plana vitrectomy (PPV) with epiretinal membrane (ERM) and ILM removal using OCT RTVue XR 100 Avanti. Methods. Retrospective analysis of OCT scans of 40 patients who underwent PPV or combined phacovitrectomy with ILM peeling for the idiopathic ERM has been carried out. The patients were divided into two groups for the study: patients with the ERM and OAG and those with ERM without glaucoma. A trend analysis of the RNFL thickness changes in 1 month and 3, 6, and 12 months was created. Results. At 1 month after surgery, the RNFL thickness increased significantly in the temporalis quadrant from 89.9 μm to 105.7 μm in patients with OAG. Comparison between group with OAG and group without glaucoma showed that the RNFLT in the temporalis quadrant decreased significantly 6 months after the surgery. Conclusion. Postoperative changes in RNFL thickness appeared to be transient, and there was temporal retardation of the retinal nerve fibers without affecting visual acuity in both groups. [ABSTRACT FROM AUTHOR]

Our study performed qualitative and quantitative studies on the corneal ultrastructure of healthy female Merino sheep of ages 4 months and 6 years old from the Argentinean Pampa. The corneas were evaluated using ex vivo laser-scanning confocal microscopy, light microscopy and transmission electron microscopy. Those studies allowed us to obtain detailed images of the corneal layers as well as quantitative data of the cellular and sub-basal nerve densities in the cornea from sheep of different ages. The density of the corneal cells was significantly different in the anterior versus the posterior epithelium and stroma. Moreover, the density of the epithelial, stromal cells and endothelial cells, as well as the sub-basal nerve density were significantly lower in adult than in young animals. Our work provided a wide-ranging description of the corneal ultrastructure of healthy female Merino sheep, which adds to the current knowledge about the ophthalmological aspects of this species and undoubtedly benefits veterinarians. [ABSTRACT FROM AUTHOR]

A 52-year-old Chinese gentleman presented with right eye floaters and photopsia over one week. His visual acuities were 20/20 bilaterally. Posterior segment examination showed a right eye swollen optic disc and central retinal vein occlusion (CRVO) associated with an area of subretinal hemorrhage adjacent to the optic disc. Fundus fluorescein (FA) and indocyanine green angiographies (ICGA) of the right eye did not demonstrate choroidal neovascularization (CNV), polypoidal choroidal vasculopathy (PCV), or retinal ischemia. Ultrasound B-scan revealed optic disc drusen (ODD). In view of good vision and absence of CNV, he was managed conservatively with spontaneous resolution after two months. Commonly, ODD may directly compress and mechanically rupture subretinal vessels at the optic disc, resulting in peripapillary subretinal hemorrhage, as was likely the case in our patient. Mechanical impairment of peripapillary circulation also results in retinal ischemia and may trigger the development of choroidal neovascularization (CNV) and/or polypoidal choroidal vasculopathy (PCV), leading to subretinal haemorrhage. Compromise in central venous outflow with increased retinal central venous pressure from the direct mechanical effects of enlarging ODD results in central retinal vein occlusion (CRVO). Patients with subretinal hemorrhage and CRVO from ODD should be monitored closely for the development of potentially sight-threatening complications. [ABSTRACT FROM AUTHOR]

PurposeTo evaluate results of 23-gauge transconjunctival sutureless vitrectomy in various indications of vitreoretinal diseases.DesignProspective, non-comparative study.Materials and methodsFifty-seven consecutive eyes of 57 patients underwent vitreoretinal surgery by one surgeon using the 23-gauge, two-step instrumentation developed by Dutch Ophthalmic Research Center Inc., for epiretinal membranes (n=24), macular holes (n=10), diabetic retinopathy (n=4), rhegmatogenous retinal detachment (n=3), silicone oil removal (n=10), and other procedures (n=4). Mean operative time and intraoperative and postoperative complications were recorded. At 1 month, postoperative visual acuity, anatomical results, and induced astigmatism measured by Orbscan (BAUSCH and LOMB laboratories Inc., Rochester, NY, USA) were analysed.ResultsMean operative time was 32.6±21.5 min. At 1 month, mean visual acuity improved from 1.09±0.82 to 0.80±0.79 logMar. Transient postoperative hypotony was the most common complication (21.1%), resolving without treatment. There was no choroidal effusion; and no postoperative endophthalmitis was observed. There were no significant changes in mean keratometry (P=0.957), mean axis (P=0.818), and power of astigmatism (P=0.860) at 1 month.ConclusionsA 23-gauge vitrectomy seems to be safe and effective for a wide range of indications for vitreoretinal surgery. Further studies are needed to compare it with 25-gauge and 20-gauge vitrectomy in larger series. [ABSTRACT FROM AUTHOR]

Noninvasive medical imaging techniques have high potential in the field of ocular imaging research. Angle closure glaucoma is a major disease causing blindness and a possible way of detection is the examination of the anterior chamber angle in eyes. Here, a simple optical method for the evaluation of angle-closure glaucoma is proposed and illustrated. The light propagation from the region associated with the iridocorneal angle to the exterior of eye is considered analytically. The design of the gel assisted probe prototype is carried out and the imaging of iridocorneal angle is performed on an eye model. [ABSTRACT FROM AUTHOR]