https://minerva-access.unimelb.edu.au/bitstream/handle/11343/280247/PIIS2214109X20304885.pdf

The Lancet Global Health Commission on Global Eye Health: vision beyond 2020.

The aim of this review was to quantify the global variation in childhood myopia prevalence over time taking account of demographic and study design factors. A systematic review identified population-based surveys with estimates of childhood myopia prevalence published by February 2015. Multilevel binomial logistic regression of log odds of myopia was used to examine the association with age, gender, urban versus rural setting and survey year, among populations of different ethnic origins, adjusting for study design factors. 143 published articles (42 countries, 374 349 subjects aged 1- 18 years, 74 847 myopia cases) were included. Increase in myopia prevalence with age varied by ethnicity. East Asians showed the highest prevalence, reaching 69% (95% credible intervals (CrI) 61% to 77%) at 15 years of age (86% among Singaporean-Chinese). Blacks in Africa had the lowest prevalence; 5.5% at 15 years (95% CrI 3% to 9%). Time trends in myopia prevalence over the last decade were small in whites, increased by 23% in East Asians, with a weaker increase among South Asians. Children from urban environments have 2.6 times the odds of myopia compared with those from rural environments. In whites and East Asians sex differences emerge at about 9 years of age; by late adolescence girls are twice as likely as boys to be myopic. Marked ethnic differences in age-specific prevalence of myopia exist. Rapid increases in myopia prevalence over time, particularly in East Asians, combined with a universally higher risk of myopia in urban settings, suggest that environmental factors play an important role in myopia development, which may offer scope for prevention.

https://bjo.bmj.com/content/bjophthalmol/early/2016/01/22/bjophthalmol-2015-307724.full.pdf

Global variations and time trends in the prevalence of childhood myopia, a systematic review and quantitative meta-analysis: implications for aetiology and early prevention

Purpose To summarize the available data on pediatric blinding disease worldwide and to present current information on childhood blindness in the United States. Methods A systematic search of world literature published since 1999 was conducted. Data also were solicited from each state school for the blind in the United States. Results In developing countries, 7% to 31% of childhood blindness and visual impairment is avoidable, 10% to 58% is treatable, and 3% to 28% is preventable. Corneal opacification is the leading cause of blindness in Africa, but the rate has decreased significantly from 56% in 1999 to 28% in 2012. There is no national registry of the blind in the United States, and most schools for the blind do not maintain data regarding the cause of blindness in their students. From those schools that do have such information, the top three causes are cortical visual impairment, optic nerve hypoplasia, and retinopathy of prematurity, which have not changed in past 10 years. Conclusions There are marked regional differences in the causes of blindness in children, apparently based on socioeconomic factors that limit prevention and treatment schemes. In the United States, the 3 leading causes of childhood blindness appear to be cortical visual impairment, optic nerve hypoplasia, and retinopathy of prematurity; a national registry of the blind would allow accumulation of more complete and reliable data for accurate determination of the prevalence of each.

An update on progress and the changing epidemiology of causes of childhood blindness worldwide

Purpose The aim of the study was a systematic review of refractive errors across the world according to the WHO regions Methods To extract articles on the prevalence of refractive errors for this meta-analysis, international databases were searched from 1990 to 2016 The results of the retrieved studies were merged using a random effect model and reported as estimated pool prevalence (EPP) with 95% confidence interval (CI) Results In children, the EPP of myopia, hyperopia, and astigmatism was 117% (95% CI: 105–130), 46% (95% CI: 39–52), and 149% (95% CI: 127–171), respectively The EPP of myopia ranged from 49% (95% CI: 16–81) in South–East Asia to 182% (95% CI: 109–255) in the Western Pacific region, the EPP of hyperopia ranged from 22% (95% CI: 12–33) in South-East Asia to 143% (95% CI: 134–152) in the Americas, and the EPP of astigmatism ranged from 98% in South-East Asia to 272% in the Americas In adults, the EPP of myopia, hyperopia, and astigmatism was 265% (95% CI: 234–296), 309% (95% CI: 262–356), and 404% (95% CI: 343–466), respectively The EPP of myopia ranged from 162% (95% CI: 156–168) in the Americas to 329% (95% CI: 251–407) in South-East Asia, the EPP of hyperopia ranged from 231% (95% CI: 61%–402%) in Europe to 386% (95% CI: 224–548) in Africa and 372% (95% CI: 253–49) in the Americas, and the EPP of astigmatism ranged from 114% (95% CI: 21–207) in Africa to 456% (95% CI: 441–471) in the Americas and 448% (95% CI: 366–531) in South-East Asia The results of meta-regression showed that the prevalence of myopia increased from 1993 (104%) to 2016 (342%) (P = 0097) Conclusion This report showed that astigmatism was the most common refractive errors in children and adults followed by hyperopia and myopia The highest prevalence of myopia and astigmatism was seen in South-East Asian adults The highest prevalence of hyperopia in children and adults was seen in the Americas

Global and regional estimates of prevalence of refractive errors: Systematic review and meta-analysis

Background. Measles kills about 2 million children annually, and there is no specific therapy for the disease. It has been suggested that vitamin A may be of benefit in the treatment of measles. Methods. We conducted a randomized, double-blind trial involving 189 children who were hospitalized at a regional center in South Africa because of measles complicated by pneumonia, diarrhea, or croup. The children (median age, 10 months) were assigned to receive either vitamin A (total dose, 400,000 IU of retinyl palmitate, given orally; n = 92) or placebo (n = 97), beginning within five days of the onset of the rash. At base line, the characteristics of the two groups were similar. Results. Although clinically apparent vitamin A deficiency is rare in this population, the children's serum retinol levels were markedly depressed (mean [±SEM], 0.405±0.021 μmol per liter [11.6±0.6 /μg per deciliter]), and 92 percent of them had hyporetinemia (serum retinol level <0.7 μmol per liter [20 μg per deciliter]). Se...

A randomized, controlled trial of vitamin a in children with severe measles

Background: Uncorrected refractive error is an avoidable cause of visual impairment Aim: To compare the magnitude and determinants of uncorrected refractive error, such as age, sex, family history of refractive error and use of spectacles among school children 6-15 years old in urban and rural Maharashtra, India Study Design: This was a review of school-based vision screening conducted in 2004-2005 Materials and Methods: Optometrists assessed visual acuity, amblyopia and strabismus in rural children Teachers assessed visual acuity and then optometrists confirmed their findings in urban schools Ophthalmologists screened for ocular pathology Data of uncorrected refractive error, amblyopia, strabismus and blinding eye diseases was analyzed to compare the prevalence and risk factors among children of rural and urban areas Results: We examined 5,021 children of 8 urban clusters and 7,401 children of 28 rural clusters The cluster-weighted prevalence of uncorrected refractive error in urban and rural children was 546% (95% CI, 544-548) and 263% (95% CI, 262-264), respectively The prevalence of myopia, hypermetropia and astigmatism in urban children was 316%, 106% and 016%, respectively In rural children, the prevalence of myopia, hypermetropia and astigmatism was 145%, 039% and 021%, respectively The prevalence of amblyopia was 08% in urban and 02% in rural children Thirteen to 15 years old children attending urban schools were most likely to have uncorrected myopia Conclusion: The prevalence of uncorrected refractive error, especially myopia, was higher in urban children Causes of higher prevalence and barriers to refractive error correction services should be identified and addressed Eye screening of school children is recommended However, the approach used may be different for urban and rural school children

Prevalence of uncorrected refractive error and other eye problems among urban and rural school children

PURPOSE: To determine the causes of severe visual impairment and blindness in children in schools for the blind in southern Karnataka state of India. METHOD: Children aged less than 16 years with a visual acuity of < 6/60 in the better eye, attending the residential schools for the blind were examined in 2005-2006, in the Karnataka state in the south of India. History taking, visual acuity estimation, external ocular examination, retinoscopy, and fundoscopy were done on all students. Refraction and low vision work-up done where indicated. The anatomical and etiological causes of severe visual impairment (< 6/60-3/60) and blindness (< 3/60 in the better eye) were classified using the World Health Organization's prevention of blindness programs' record system. RESULTS: A total of 1,179 students were examined, 891 of whom fulfilled the eligibility criteria. The major anatomical sites of visual loss were congenital anomalies (microphthalmos, anophthalmos) (321, 35.7%), corneal conditions (mainly scarring due to vitamin A deficiency, measles, trauma) (133, 14.9%), cataract or aphakia in 102 (11.4%), and retinal disorders (mainly dystrophies) in 177 children (19.9%). Nearly one-fourth of children were blind from conditions which could have been prevented or treated (27.8%), 87 of whom were referred for surgery. Low vision devices improved near acuity in 27 children (3%), and 43 (4.8%) benefited from refraction. CONCLUSIONS: Congenital anomalies, cataract, and retinal conditions account for most of the blindness in children.

The pattern of childhood blindness in Karnataka, South India.

The World Health Organization (WHO) Global Action Plan (GAP) 2014-19 emphasize providing Comprehensive Eye Care (CEC) using the health system approach to achieve Universal Eye Health Coverage (UEHC). An important aspect of CEC is Primary Eye Care (PEC). The scope of PEC varies significantly with primary health workers providing PEC in most parts of the developing world, whereas in developed nations PEC is provided by specialized personnel such as optometrists. This article focuses on delivery of PEC models in India, specifically through the vision center (VC) approach. VCs are part of a larger eye care network and provide PEC in remote rural areas of the country. The authors describe the how PEC is delivered in more than 300 VCs operated by six mentor hospitals in India under the Global Sight Initiative (GSI). Key factors compared include: The role of leadership; human resource planning, including recruitment and retention; service delivery; leveraging technology for planning and reaching key populations; financial sustainability; supply chain management; and quality and monitoring. It also discusses issues to be considered to strengthen VCs as we move ahead towards our collective goal of achieving UEHC and eliminating avoidable blindness.

Primary eye care in India - The vision center model.

Purpose: Childhood cataract is an important cause of avoidable blindness in children. The study aimed to investigate the outcome of surgery in cataracts with delayed presentation which had been operated upon as new pediatric ophthalmology centers were set up in India.Methods: This was a retrospective interventional case series from a community eye care center in Western India. Demographic, surgical, pre-operative and post-operative details were obtained from the patients records and entered into Microsoft excel and statistical analysis conducted using SPSS-11 software (SPSS, Chicago, IL). Vision was tested 6 weeks after surgery. The predictors of good vision (≥6/18) were identified by regression analysis. If the interval between detection of cataract in children and their presentation for surgery was more than 18 months for developmental and 6 months for congenital the cataract was defined having a delayed presentation.Results: Five hundred and twenty nine eyes of 437 children aged 2 months to 16 years we...

Delayed Presentation of Cataracts in Children: Are they Worth Operating Upon?

Purpose: International and national programs to control vitamin A deficiency disorders (VADD) among children in developing countries are reducing the magnitude but VADD still occurs in deprived populations. The purpose of the study was to estimate the prevalence of and identify risk factors for xerophthalmia in children aged 6–71 months living in slums in Pune, India in 2003. Methods: Children were enrolled into a cross sectional study from randomly selected Anganwadis (kindergartens) in selected slums using proportional to size sampling. Parents/caregivers were interviewed by social workers about night blindness, risk factors for VADD at individual and household levels, intake of vitamin A rich foods, and history of vitamin A supplementation. Children were examined for signs of xerophthalmia by an ophthalmologist. Risk factors for xerophthalmia were explored using univariate and multivariate regression analysis. Results: 1,589 children were examined (response rate 80.2%) 22 of whom had xerophthalmia, pre...

Kuldeep Dole

Papers

Prevalence of uncorrected refractive error and other eye problems among urban and rural school children

The pattern of childhood blindness in Karnataka, South India.

Primary eye care in India - The vision center model.

Delayed Presentation of Cataracts in Children: Are they Worth Operating Upon?

Prevalence and Determinants of Xerophthalmia in Preschool Children in Urban Slums, Pune, India—A Preliminary Assessment