Refractive Errors, Myopia, and Presbyopia
Ching-Yu Cheng, Tien Yin Wong in Ophthalmic Epidemiology, 2022
Myopia is the most common ocular disorder worldwide.4 It is commonly defined as a spherical equivalent refraction (SER) of –0.50 D or less in either eye. High myopia is further defined as a SER of –6.00 D or less. Axial myopia is associated with excessive axial elongation of the globe. Notably, globe elongation, especially in high myopia, leads to vision-threatening complications, including MMD, RD, OAG, and cataracts.2,3,5 A recent meta-analysis reveals that low, moderate, and high myopia are all associated with increased risks of ophthalmic complications at various degrees, including MMD (odds ratio [OR] = 13.57, 72.74, and 845.08 respectively), RD (OR = 3.15, 8.74, and 12.62), posterior subcapsular cataract (OR = 1.56, 2.55, and 4.55), nuclear cataract, and OAG (OR = 1.59 and 2.92 in low and moderate to high myopia respectively).3
Surgical treatment of macular holes
A Peyman MD Gholam, A Meffert MD Stephen, D Conway MD FACS Mandi, Chiasson Trisha in Vitreoretinal Surgical Techniques, 2019
In 1991, Kelly and Wendel65 published the first report of successful closure of idiopathic macular holes in 30 of 52 eyes (58%) with pars plana vitrectomy, removal of adherent cortical vitreous, stripping of ERMs, air–fluid exchange, and tamponade with a nonexpansile concentration of sulfur hexafluoride gas. Vision improved by 2 or more lines in 22 of 30 (73.3%) eyes in which a macular hole was successfully closed. Several authors have since reported surgical results with closure of macular holes ranging from 58% to 100%, with improvement in vision by 3–5 lines in most patients with successful hole closure.66–;84 Surgical treatment is currently indicated for stage 2, 3, and 4 macular holes. Visual improvement depends on successful closure of the hole and the duration of symptoms. Eyes with symptoms for less than 6 months have better visual prognosis. Improved anatomic and functional success is generally associated with smaller hole size, shorter duration of symptoms, and better initial acuity.66,80,81,85,86 Visual improvement for up to 3 years after surgery has been noted after successful macular hole surgery.83,84 Patients with proliferative diabetic retinopathy may have a worse prognosis.87 Good anatomic, but poorer visual acuity, results have been obtained in patients with high myopia.88 Patients with prominent macular drusen appear to do well both anatomically and visually after macular hole surgery.89
Management of the Hearing Impaired Child
John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed in Paediatrics, The Ear, Skull Base, 2018
A comprehensive ophthalmic assessment is required as deaf children are heavily reliant on the sense of vision in order to develop efficient communication skills and explore the world around them. Any ophthalmic disorder needs to be recognized as soon as possible to optimize language development (spoken or sign, or both). These disorders may be correctable (such as myopia) or treatable (such as cataract). Those children with non-correctable and non-treatable visual disorders, like retinitis pigmentosa in Usher syndrome, require multiple environmental adaptations and appropriate support services and information.97
Effects of online family health education on myopia prevention in children by parental myopia: a randomized clinical trial
Published in Clinical and Experimental Optometry, 2023
Jiayu Zhang, Lili Wang, Lan Guo, Yangfeng Guo, Feng Zhao, Yin Hu, Qian Li, Xueying Du, Xueqing Deng, Nali Deng, Xiao Yang, Ciyong Lu
Another possible explanation is that the COVID-19 pandemic led to a nationwide school closure in China from January to May 2020, and Chinese children were required to learn online at home during this period, which may have an impact on the eyesight of students.26 Several studies have reported an increase in the incidence and development of myopia among schoolchildren because of the significant decrease in outdoor time and increase in screen time during the COVID-19 pandemic.27–29 In this unfavourable visual environment during the COVID-19 pandemic, children with non-myopic parent in the intervention group spent more time outdoors than the control group, which proved the effectiveness of online home health education. This study suggests that the key to preventing myopia in children is to increase outdoor time.
Low Dose Atropine in Preventing the Progression of Childhood Myopia: A Randomised Controlled Trial
Published in Current Eye Research, 2023
Isha Sharma, Gopal K. Das, Jolly Rohatgi, Pramod K. Sahu, Pragti Chhabra, Rahul Bhatia
Myopia management options using various optical and surgical methods are well known. However, the rising number of cases suggest that prevention, although difficult to achieve if exact cause of myopia is not established, should be emphasized upon besides the current approach of treating myopia, else the burden of this existing global public health issue may worsen. The options available to slow the progression include adapting healthy ocular habits, like increasing time outdoors and reducing the duration of near activities,8 which requires immense amount of counselling and motivation and is difficult considering the busy parental schedules. Other options like orthokeratology,9 soft contact lens10 have shown to be effective, but the concerns of hygiene and patient compliance is an issue, more so in developing countries where such a preventive modality for reducing myopia progression may not be possible on a large scale.
Pre-clinical and cellular toxicity evaluation of 7-methylxanthine: an investigational drug for the treatment of myopia
Published in Drug and Chemical Toxicology, 2021
Harjeet Singh, Nikhil Shri Sahajpal, Harmanpreet Singh, Vanita Vanita, Partha Roy, Surinder Paul, Shashank Kumar Singh, Inderjit Kaur, Subheet Kumar Jain
Myopia, also known as near-sightedness, is a state of refraction in which parallel rays of light do not focus on the retina but focus in front of a resting eye. A refractive error of greater than 0.25 or 0.50 diopter is defined as myopia (Saw et al. 1996). Myopia remains the most prevalent refractive error with its prevalence varying across different regions and races. The greater time spent on near sighted work i.e., computer, mobile phone, video game, indoor lifestyle, higher educational setup, and history of myopia in family have been reported as increased risk factors for myopia. The prevalence remains higher in urban regions and in East Asian population. The prevalence in children indicates that the Asian population, specifically, the Chinese population is more susceptible to myopia compared to the western population. Whereas, no such clear distinction in susceptibility emerges in adult population of age greater than 40 years (Pan et al.2012). Furthermore, it is much more prevalent in industrialized countries and in cities as compared to non-industrialized and rural areas (Saw et al.2006). The environmental factors have a considerable influence on the development of myopia and it cannot be explained only by a genetic model (Bar et al.2005), as its origin remains to be both genetic and environmental.