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Ageing
Published in Henry J. Woodford, Essential Geriatrics, 2022
Around 13% of people aged over 75 are visually impaired (defined as scoring < 6/18 on Snellen acuity testing).68 Age-related changes include reduced lens flexibility and altered light refraction, cataract formation, reduced ciliary muscle contractility, macular degeneration, reduced eye movements and slower visual processing. Presbyopia is a term for the loss of accommodation seen with advancing age. It is caused by changes in the lens and ciliary muscle, which can usually be corrected with glasses. Binocular visual loss is related to refractive errors in around 32% of affected people.68 The commonest eye diseases affecting vision in older age are age-related macular degeneration (AMD) (36% of those with visual impairment), cataracts (25%), glaucoma (8%) and diabetic retinopathy (2%).
Teager-Kaiser Boost Clustered Segmentation of Retinal Fundus Images for Glaucoma Detection
Published in K. Gayathri Devi, Kishore Balasubramanian, Le Anh Ngoc, Machine Learning and Deep Learning Techniques for Medical Science, 2022
P M Siva Raja, R P Sumithra, K Ramanan
Glaucoma is an eye disease and it leads to blindness. The cruel vision-related diseases are ignored by early identification and accurate treatment of glaucoma. Many researchers are carried out for Glaucoma disease identification. However, segmentation plays a significant task that correctly detects glaucoma.
Introduction
Published in Arwa Ahmed Gasm Elseid, Alnazier Osman Mohammed Hamza, Computer-Aided Glaucoma Diagnosis System, 2020
Arwa Ahmed Gasm Elseid, Alnazier Osman Mohammed Hamza
Glaucoma is dangerous as an ocular disease because it is the second-leading cause of blindness with about 60 million glaucomatous cases globally (Lim et al., 2010), and it is responsible for 5.2 million cases of blindness based on (Lim et al., 2012), with more than 90% of the patients unaware of the condition (Zhang et al., 2014). In 2014, the World Health Organization (WHO) reported that 285 million people were estimated to be visually impaired worldwide: 39 million were blind and 246 million had low vision, in which 80% of all visual impairment could be prevented or cured. The WHO also stated that around 90% of the world’s visually impaired people lived in low-income settings (Koprowski, 2014). Clinically, glaucoma is a chronic eye disease that damages the optic nerve progressively as the disease progresses, causing more optic head damage due to loss of peripheral vision and resulting in a gradual loss of vision. Finally, glaucoma is associated with total blindness. Glaucoma must be managed at the early stage to prevent irreversible optic nerve damage. Treatment can prevent progression of the disease. Therefore, early detection of glaucoma is important to prevent blindness.
Monolith/Hydrogel composites as triamcinolone acetonide carriers for curing corneal neovascularization in mice by inhibiting the fibrinolytic system
Published in Drug Delivery, 2022
Cixin Huang, Xia Qi, Huilin Chen, Chao Wei, Xiaolin Qi, Hongwei Wang, Hua Gao
The in vitro degradability of the monolith/hydrogel composites was assessed by calculating the mass ratio of the residual composite and total composite. As is shown in Figure S3 (Supporting information), mass percentages of the hydrogels, the monoliths, and the composites decreased to 67.7% ± 9.5%, 95.7% ± 1.4%, and 94.8% ± 0.5% at 1 d, respectively. When the immersion time extended to 6 days, hydrogel was almost completely degraded, while there was no significant change in the mass percentages of monolith and the composite, indicating the poor degradability of monolith in the composite. However, it can be stated that the improved loading efficiency and the good biocompatibility allowed the composite to act as a TA carrier on corneal neovascularization. The implantation of sustained TA carriers can afford a long-term therapeutic effect; however, patients would find it difficult to accept the operation, which limits the wide clinical application of the monolith/hydrogel composite. Ophthalmic solutions are an acceptable way for the treatment of eye diseases. However, a high therapeutic concentration was required owing to its low bioavailability, which can cause ocular or even systemic side effects. Thus, further work can be focus on the development of monolith/hydrogel composite based ophthalmic solution for curing corneal neovascularization.
Effect of image-guided systems in phacoemulsification with intraocular lens (IOL) implantation: a systematic review and meta-analysis
Published in Computer Assisted Surgery, 2022
Yang Su, Min Fu, Yifan Chen, Rui Qiao, Guo-Guo Yi
Cataract is a group of opacity in the lens as a common feature of the disease, one of the major blinding eye diseases in the world, and surgery is the main treatment. 34.7%–47.3% of cataract patients had corneal cylinder≥ 1.0 D, which seriously affected the visual function after refractive surgery [1]. Intraocular lens (IOL) implantation is a safe and effective modality in such cases to help treat cataract at the same time of correcting regular cylinder of cornea [2,3]. Accurate measurement of preoperative corneal cylinder, IOL axis alignment along the desired corneal meridian and intraoperative positioning are necessary. One degree of misalignment results in 3.3% decrease in the correction of cylinder, and 30° misalignment effectively increase the amount of preoperative cylinder [4–6].
Management of Bi-Punctal Stenosis by One-Snip Punctoplasty Combined with Silicone Intubation
Published in Orbit, 2022
This was a prospective interventional case series which included patients with epiphora due to bi-punctal stenosis. An informed consent was signed by all patients, and the study adhered to the principles of the Declaration of Helsinki. Patients’ evaluation included: detailed history including the duration of symptoms, presence of any other associated symptoms as itching, foreign body sensation, discharge, history of previous ocular disorders, medications, or surgeries. Examination included thorough ophthalmological examination to exclude eyelid malpositions and external eye diseases. Schirmer’s test and tear break up time (TBUT) evaluation were done for the exclusion of dry eye. Wetting of Schirmer’s filter paper of 10 mm or more and TBUT of 10 seconds or more were considered normal.