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Ophthalmological system (eyes)
Published in David Sales, Medical IELTS, 2020
However, floaters are reported more frequently, especially against a pale background, and if there is no change in visual acuity they are not likely to be associated with serious eye disease, in contrast to a short-sighted person who suddenly has a change in visual acuity and who sees sparks or stars, who may have a retinal detachment.
Flashing Lights and Floaters
Published in Amy-lee Shirodkar, Gwyn Samuel Williams, Bushra Thajudeen, Practical Emergency Ophthalmology Handbook, 2019
Patients describe their symptoms with themes that have a common thread. They describe floaters as flies, cobwebs, worms, squiggly lines, strands or spots and so forth in their field of vision and find that these are more prominent against light coloured backgrounds like white walls or against a bright sky. These objects move with eye movement.
Seeing
Published in Patrick Rabbitt, The Aging Mind, 2019
On their way from the lens to the retina, photons of light face an additional challenge: a jelly-like packing in the eye, the vitreous humour, which in old age is increasingly contaminated by bits of organic detritus that opticians call “floaters”. When we turn our closed eyelids to a bright light the shadows of these scraps drift across our visual fields like shoals of crinkling corpses of amoebae. As we grow old, floater swarms become increasingly dense, and, literally, dim our view of the world. Apart from blocking out light, the sudden shifts of floater-shoals are often mistaken for moving objects in peripheral vision. They should be taken seriously because high densities of floaters, especially if they occur suddenly, may be a warning of a detaching retina that urgently demands medical help to forestall blindness.
Macro- and Microscale Properties of the Vitreous Humor to Inform Substitute Design and Intravitreal Biotransport
Published in Current Eye Research, 2021
Nguyen K. Tram, Courtney J. Maxwell, Katelyn E. Swindle-Reilly
The phase separation of the vitreous compromises its ability to function as a protective structure for the surrounding ocular tissues and causes complications including rhegmatogenous retinal detachment, macular holes, vitreous hemorrhage, and vitreous floaters.51 Vitreous floaters, which can be seen as floating shadows in one’s field of vision, are large fibrous aggregations floating in pockets of liquefied vitreous that cast shadows on the retina, interfering with vision. When the liquid pockets develop at the back of the eye, areas of high stress develop where the vitreous connects to the retina, potentially causing retinal tears or macular holes. Thereafter, the liquid component of the vitreous might leak underneath the retina layer through the tear in the retina, lifting the retina away from the choroid and causing retinal detachment. Blood from the retinal vessels may bleed into the vitreous, creating vitreous hemorrhage which might necessitate surgical removal of the tissue if the vitreous hemorrhage does not clear on its own. The degree of phase separation of the vitreous humor has been correlated to signs of cataract formation52 due to the diminished oxygen gradient and the ability of oxygen to travel from the retina to the lens via convectional mixing. Considering the serious complications with the phase-separated vitreous humor, it is important to understand the changing mechanical properties of the aging vitreous.
Evaluation of Available Online Information Regarding Treatment for Vitreous Floaters
Published in Seminars in Ophthalmology, 2021
Meghana Kalavar, Sasha Hubschman, Julia Hudson, Ajay E. Kuriyan, Jayanth Sridhar
For vitreous floaters, a common eye complaint with generally benign pathology and controversial therapeutic options, this issue is particularly salient. The majority of the population experiences vitreous floaters in their lifetime, including up to 76% of smartphone users.4 Vitreous floaters often occur as a result of molecular changes to the collagen extracellular matrix in the eye, and patients describe floaters as bubbles, dark spots, bugs or cobwebs in the temporal visual field.5 While vitreous floaters can occur for many reasons, including inflammation, they most commonly occur due to aging.5 Objectively quantifying the severity of floaters is challenging as patients do not usually have a loss of visual acuity, although correlation with contrast sensitivity has been demonstrated.6,7 Since the impact floaters have on a patient’s quality of life is primarily subjective, the treatment is predominantly patient-driven, increasing the likelihood that patients will turn to the internet for information. Given the benign nature of most floaters, the most common management in the absence of retinal pathology is observation.8 When treatment is considered, options include Nd-Yag laser vitreolysis, cataract surgery combined with deep anterior vitrectomy, and pars plana vitrectomy.9
Spectrum of Newly Diagnosed Cytomegalovirus Retinitis in a Developing Country in the HAART Era
Published in Ocular Immunology and Inflammation, 2020
Simar Rajan Singh, Mohit Dogra, Savleen Kaur, Priya Bajgai, Basavaraj Tigari, Sabia Handa, Deeksha Katoch, Vishali Gupta, Mangat R. Dogra, Aman Sharma, Ramandeep Singh
A total of 87 eyes of 52 patients were diagnosed with CMV retinitis during the study period. Five eyes (5.7%) with CMV retinitis were misdiagnosed at the initial presentation, with acute retinal necrosis being the most common misdiagnosis in 3 eyes and tubercular uveitis in 2 eyes. The mean decimal BCVA was 0.27 ± 0.32 with low vision at presentation in 60 eyes (69%). Sixteen eyes (18.4%) were classified as MSVI and 44 eyes (50.6%) were classified as blind. Seven of these 44 eyes had no light perception. Eight patients were bilaterally blind at presentation. Three patients developed second eye involvement during the course of treatment of the first eye. Diminution of vision was the most common presenting feature in 44 patients followed by floaters in 2 patients. Six patients, 1 of them with bilateral disease, were asymptomatic and diagnosed incidentally on referral by the ART center for routine screening examination. Fifty-five percent of patients had symptoms for duration of less than 3 months. Symptom duration of > 1year was associated with the presence of CD4 counts > 50 cells/µL (p = 0.04). (Table 2)