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Pharmacology of Therapeutic Agents in Photomedicine
Published in Henry W. Lim, Nicholas A. Soter, Clinical Photomedicine, 2018
Ira C. Davis, Matthew J. Stiller, Jerome L. Shupack
The major concern with the use of chloroquine and hydroxychloroquine is the possibility of irreversible retinopathy. The incidence of retinopathy, which is related to the daily dose, is low (approximately 300 reported cases worldwide) (39). Severe retinopathy may progress even after discontinuation of medication. Amsler grid testing every 2 weeks offers the best screening test to detect early retinopathy and visual field defects (40). Although corneal deposition and a loss of accommodation due to ciliary body dysfunction may occur, these complications are rarely symptomatic and do not require drug discontinuation (41). Corneal deposits and edema have been noted with quinacrine (42). However, only one case of quinacrine-associated retinopathy has been reported. The patient took the medication, which she had already taken for 12 years, for an additional 4 years without any progression of her retinopathy (43).
Eyesight standards for beach lifeguards
Published in Mike Tipton, Adam Wooler, The Science of Beach Lifeguarding, 2018
The Amsler grid test for the central 10 degrees of visual field uses the Amsler recording chart. This chart consists of a grid of black lines on a white background. The chart is 10 cm × 10 cm, with the grid comprising 0.5 cm squares. The subject is requested to look at a black dot drawn in the centre of the grid at a distance of 30 cm. While conducting the test, the subject wears near correction, and one eye is occluded. The subject is requested to indicate whether any parts of the grid are blurred or distorted in any way. In addition, the subject is requested to mark with a pen the position of these abnormalities on the chart. In this manner, the test detects any abnormalities in the central 10 degrees of field of vision.
The retina, optic nerve and vitreous humour
Published in Mary E. Shaw, Agnes Lee, Ophthalmic Nursing, 2018
The patient will be asked to read the Amsler grid to assess the size and position of the central blur. A fundal fluorescein angiogram will highlight the leaking of serous fluid from the choriocapillaries through the defect in the pigment epithelium. Laser treatment can be applied to seal the leaking vessels. The condition usually resolves itself within 2–4 months.
Acute Unilateral Central Serous Chorioretinopathy after Immunization with Pfizer-BioNTech COVID-19 Vaccine: A Case Report and Literature Review
Published in Seminars in Ophthalmology, 2022
Palaniraj Rama Raj, Paul A Adler, Rajeev Chalasani, Sue Ling Wan
On examination, his right visual acuity was 6/12, correcting to 6/9 with pinhole. His left visual acuity was 6/6. Intraocular pressure measurements and ocular motility tests were normal. His visual fields were normal with confrontation testing. Pupillary responses were normal with no relative afferent pupillary defects or anisocoria. His optic nerve function was normal, with equal bilateral light saturation and normal colour vision on Ishihara testing. Anterior segment examination was within normal limits and there was no evidence of uveitis. Amsler grid testing revealed mild distortion of the vertical grid lines centrally in his right eye and normal findings in his left eye. Dilated fundus examination revealed a loss of foveal reflex and an elevated appearance of the macula in the right eye. There was no evidence of posterior uveitis, retinal haemorrhages, drusen, pigmentary or vascular abnormalities. Posterior segment examination of the left eye was normal.
Vitreomacular disorders: a review of the classification, pathogenesis and treatment paradigms including new surgical techniques
Published in Clinical and Experimental Optometry, 2021
Mali Okada, Daniel Chiu, Jonathan Yeoh
In general, no intervention is required for VMA as it is usually asymptomatic and part of the natural history of PVD evolution. Similarly, some patients with mild VMT can also be managed by observation alone. A recent study evaluating the natural history of VMT over 17 months found that the majority of eyes remain stable (60%), some improve (20%) whilst others progress (8%) or develop FTMH (12%).36 Therefore, observation with repeat imaging may be reasonable for those who are asymptomatic. There is no consensus on how often these patients need to be monitored, however, careful evaluation is required using detailed OCT scans (with narrow scanning intervals) to ensure an FTMH is not missed. This is especially in patients with focal VMT (Gass Stage 1) or history of FTMH in the fellow eye, where more frequent monitoring may be warranted. It is unclear however which patients with VMT will have spontaneous resolution and which will develop into FTMH as no reliable prognostic factors have so far been found.36 Alternatively, patients shown to have stable anatomy and vision may also benefit from self-monitoring with Amsler grid, without the need for life-long OCT imaging and follow up.
Management of inflammatory choroidal neovascular membranes
Published in Expert Review of Ophthalmology, 2021
Rachael Niederer, Asaf Bar, Haya Al-Ani, Lazha Sharief, Shaul Sar, Adi Segal, Sue Lightman, Oren Tomkins-Netzer
Although an uncommon complication of posterior and panuveitis, CNV poses a significant risk to vision, resulting in rapid and lasting vision loss. Cases with chorioretinal scarring, particularly PIC, MFC or POHS, have an increased risk of developing CNV. Clinicians should be vigilant and guide patients to report any symptoms related to CNV (metamorphopsia, decreased vision or scotomas). Regular use of an Amsler grid for self-testing, is advised in high-risk cases or when previous CNV has affected vital regions, such as the optic nerve or fovea. Once diagnosis is reached, prompt treatment should be initiated with anti-VEGF injections, guided by repeat retinal imaging (FA, OCT, OCTA). Use of corticosteroids and second-line immunosuppression agents should be considered in cases with active inflammation or when recurrences have occurred. Through close follow-up and an aggressive treatment approach, vision loss can be reduced and long-term functional vision maintained.