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Ageing
Published in Henry J. Woodford, Essential Geriatrics, 2022
Glaucoma typically causes a loss of peripheral vision or visual field defects (scotomas). It is related to reduced aqueous humour outflow that results in an increased intraocular pressure (> 21 mmHg). Primary open-angle glaucoma is an insidious disease caused by a blockage of flow in the trabecular meshwork, which results in gradual damage to the optic nerve. A large cup to disc ratio is seen on ophthalmoscopy. It is usually managed initially with eye drops, such as prostaglandin analogues (e.g. latanoprost) or beta-blockers (e.g. timolol). Secondary treatments include acetazolamide, sympathomimetics (e.g. brimonidine eye drops) and surgical iridectomy. Primary angle-closure glaucoma is caused by blockage of flow into the anterior chamber. It causes an acute red-eye and should be urgently referred to an ophthalmologist.
Diabetic Neuropathy
Published in Jahangir Moini, Matthew Adams, Anthony LoGalbo, Complications of Diabetes Mellitus, 2022
Jahangir Moini, Matthew Adams, Anthony LoGalbo
Ischemic optic neuropathy occurs when blood does not flow normally to the optic nerves, causing long-term damage. Vision is lost in one or both eyes. This disease can affect central or peripheral vision – or both. Vision loss is usually permanent, though many affected individuals still retain some amount of peripheral vision. Diabetes is one of the common causes of ischemic optic neuropathy. There are two general subtypes of this disease: Arteritic and nonarteritic. The arteritic form is caused by temporal arteritis, also known as giant cell arteritis. The more common nonarteritic form is caused by cardiovascular risk factors that include diabetes mellitus, hypertension, and high cholesterol. It usually occurs in slightly younger patients and is less likely to cause total loss of central vision. The arteritic form usually involves complete or nearly complete vision loss.
Paper 1
Published in Aalia Khan, Ramsey Jabbour, Almas Rehman, nMRCGP Applied Knowledge Test Study Guide, 2021
Aalia Khan, Ramsey Jabbour, Almas Rehman
Central retinal vein occlusion causes painless loss of vision and is more common in the elderly. It is associated with hypertension and chronic glaucoma. On examination, the retina exhibits a ‘stormy sunset’ appearance due to haemorrhages near engorged vessels. Peripheral vision is better repaired than central vision. Laser coagulation has been shown to be beneficial in some cases.
Perceptions of potential barriers to soft contact lens wear among university students in Jordan
Published in Clinical and Experimental Optometry, 2023
Mera F Haddad, May M Bakkar, Mohammad Al Qadire
Compared to spectacles, contact lenses provide many benefits. These include better field of view, since there is no obstruction in the field of vision that could possibly be caused by frames when wearing spectacles. Contact lenses are also considered a better solution to correct high refractive errors and irregular astigmatism through providing better visual performance, reducing spherical aberration and prismatic effect associated with high refractive error.7 Contact lenses also enhance peripheral vision through lens movement during eye rotation.8 Additionally, they are more comfortable than spectacles as they do not bear any weight on the face and ears beside the preferred cosmetic appearance achieved with contact lenses compared to spectacles.9,10 Quality of life for children and teens has been greatly improved with contact lenses compared to spectacles. Contact lenses improve how children feel about their appearance, and increase participation in physical activities and social acceptance, resulting in greater satisfaction of their refractive error correction.10–12
Impact of visual impairment following stroke (IVIS study): a prospective clinical profile of central and peripheral visual deficits, eye movement abnormalities and visual perceptual deficits
Published in Disability and Rehabilitation, 2022
Fiona J. Rowe, Lauren R. Hepworth, Claire Howard, Kerry L. Hanna, Jim Currie
Impaired vision following stroke is well recognised and reported, including eye movement abnormalities, visual perceptual deficits, reduced central vision and peripheral visual field loss [1]. Whilst visual inattention and visual field loss are most widely recognised as visual consequences of stroke, reduced central vision is more common but is recognised less [1–3]. We have reported point prevalence of central and peripheral vision loss previously as 56% and 28% respectively [2]. Ocular alignment and motility abnormalities also occur frequently with a reported prevalence of up to 68% [4]. Less is reported about disorders of visual perception (other than visual inattention). These are usually described in case reports or small case series but there are few collective reports of visual perception disorders in stroke survivor cohort studies [5].
A Review of Studies of the Association of Vision-Related Quality of Life with Measures of Visual Function and Structure in Patients with Glaucoma in the United States
Published in Ophthalmic Epidemiology, 2021
Naira Khachatryan, Maxwell Pistilli, Maureen G. Maguire, Angela Y. Chang, Marissa R. Samuels, Kristen Mulvihill, Rebecca J. Salowe, Joan M. O’Brien
The NEI VFQ-25 has the following vision-targeted subscales: (i) global vision rating (General Vision), (ii) difficulty with near vision activities (Near Activities), (iii) difficulty with distance vision activities (Distance Activities), (iv) limitations in social functioning due to vision (Vision-Specific Social Functioning), (v) role limitations due to vision (Vision-Specific Role Difficulties), (vi) dependency on others due to vision (Vision-Specific Dependency), (vii) mental health symptoms due to vision (Vision-Specific Mental Health), (viii) driving difficulties (Driving), (ix) limitations with peripheral vision (Peripheral Vision), (x) limitations with color vision (Color Vision), (xi) ocular pain (Ocular Pain). In addition, it includes a self-rated general health questionnaire (General Health). The composite score ranges from 0 to 100, with 0 representing extreme disability related to vision and 100 representing minimal to no disability.