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Marine Algae in Diabetes and Its Complications
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Current treatments for diabetic retinopathy include local treatments: 1) laser treatments (panretinal laser photocoagulation therapy, focal/grid laser) indicated in peripheral ischemia associated with neovascular proliferation (Simó and Hernández, 2014); 2) vitrectomy for vitreous hemorrhage and cryotherapy for retinal detachment (Bressler et al., 2018); 3) intravitreal steroids (fluocinolone acetonide insert [Retiser, Iluvien], dexamethasone [Ozurdex], triamcinolone acetonide [Kenacort Retard], and anti-TNF-α [infliximab, adalimumab]) for inflammation (Reddy et al., 2018), intravitreal injections of anti–vascular endothelial growth factor (VEGF) antibodies (aflibercept [Eylea], ranibizumab [Lucentis], pegaptanib [Macugen]), bevacizumab [Avastin]) against VEGF-mediated retinopathy (Wang and Lo, 2018). Systemic treatments include traditional approaches to the treatment of hyperglycemia (Wang and Lo, 2018).
A perspective of contemporary cataract surgery: the most common surgical procedure in the world
Published in Journal of the Royal Society of New Zealand, 2020
Charles N. J. McGhee, Jie Zhang, Dipika V. Patel
A longer term, but uncommon, risk of routine cataract surgery is that of retinal detachment. A large, retrospective study performed within the Auckland region revealed that the rate of rhegmatogenous retinal detachment following cataract surgery was low at 1.17%. The risk of developing this complication was much higher in patients younger than 50 years (5.17%) and lower in those older than 70 years (0.64%). The median interval between cataract surgery and development of the retinal detachment was more than three years (39 months) (Russell et al. 2006). The reason for the age-associated difference in risk of retinal detachment remains uncertain but has been postulated to be linked to the induction of a posterior vitreous detachment. A subsequent study showed that the incidence of posterior vitreous detachment in pseuophakic eyes (50.8%) in the sixth decade is higher than in eyes that retain the natural crystalline lens (20.8%) (Hilford et al. 2009).
Phase retrieval for studying the structure of vitreous floaters simulated in a model eye
Published in Journal of Modern Optics, 2021
Varis Karitans, Sergejs Fomins, Maris Ozolinsh
Vitreous floaters belong to a class of entoptic phenomena and are experienced by most people as chains, bubbles, cobwebs and other structures floating in the field of view. Vitreous floaters are transparent phase objects, i.e. cells, fibrils, clumps of proteins floating in a liquified vitreous body [1,2]. Typical size of the elements causing vitreous floaters lies in the range from a few to few tens of micrometers [3]. Vitreous floaters manifest themselves as diffraction patterns due to the mismatch between the refractive indices of the floating elements and the surrounding media [4,5]. In most cases, vitreous floaters cause merely visual discomfort and do not indicate any serious ocular condition, however, a sudden increase in the number of vitreous floaters may point to retinal detachment, inflammation, hemorrhage, or other pathologies. In most cases, people are able to adapt to vitreous floaters, however, if vitreous floaters become symptomatic, patients may want to remove them. Currently, vitreolysis and vitrectomy are the most efficient treatment options [6], however, both options are associated with high risks (retinal detachment, tears, hemorrhage, burns and others) and their necessity must be carefully considered. In order to neutralize vitreous floaters safely, a non-invasive method is preferred. A reasonable and safe method how to cancel or reduce the effects of vitreous floaters can be based on spatial modulation of the light entering the eye. In order to know the required modulation of the incoming light, the structure of the elements causing vitreous floaters must be determined. Once the structure of these elements has been determined, the shape of a wavefront modulator can be adjusted so that the phase distortions caused by the floating elements can be eliminated. Currently, optical coherence tomography (OCT) [7] and ultrasonography [8] can be used to determine the structure of elements floating in a liquified vitreous body. These methods, however, can be difficult to be incorporated into an optical system performing the dual task, i.e. analysing the structure of the floating elements and compensating the phase distortions.