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3,098 result(s) for "Refractive error"
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Refractive error and visual impairment in Ireland schoolchildren
AimTo report refractive error prevalence and visual impairment in Republic of Ireland (henceforth 'Ireland') schoolchildren.MethodsThe Ireland Eye Study examined 1626 participants (881 boys, 745 girls) in two age groups, 6–7 years (728) and 12–13 years (898), in Ireland between June 2016 and January 2018. Participating schools were selected by stratified random sampling, representing a mix of school type (primary/postprimary), location (urban/rural) and socioeconomic status (disadvantaged/advantaged). Examination included monocular logarithm of the minimum angle of resolution (logMAR) presenting visual acuity (with spectacles if worn) and cycloplegic autorefraction (1% Cyclopentolate Hydrochloride). Parents completed a questionnaire to ascertain participants’ lifestyle.ResultsThe prevalence of myopia (spherical equivalent refraction (SER): ≤−0.50 D), hyperopia (SER: ≥+2.00 D) and astigmatism (≤−1.00 DC) among participants aged 6–7 years old was 3.3%, 25% and 19.2%, respectively, and among participants aged 12–13 years old was 19.9%, 8.9% and 15.9%, respectively. Astigmatic axes were predominately with-the-rule. The prevalence of ‘better eye’ presenting visual impairment (≥0.3 logMAR, with spectacles, if worn) was 3.7% among younger and 3.4% among older participants. Participants in minority groups (Traveller and non-white) were significantly more likely to present with presenting visual impairment in the ‘better eye’.ConclusionsThe Ireland Eye Study is the first population-based study to report on refractive error prevalence and visual impairment in Ireland. Myopia prevalence is similar to comparable studies of white European children, but the levels of presenting visual impairment are markedly higher than those reported for children living in Northern Ireland, suggesting barriers exist in accessing eye care.
Baseline characteristics of children in the Early Glasses Study
Purpose The relationship between refractive error at age 1 and the risk of developing amblyopia or accommodative esotropia, and the protection offered by early glasses, is unknown. These are determined in the Early Glasses Study, a prospective, population-based, longitudinal, randomized controlled study. We report baseline findings. Methods Healthy children aged 12–18 months were recruited at Children’s Healthcare Centres (CHCs) and received an entry orthoptic examination followed by cycloplegic retinoscopy. Children with amblyopia, strabismus, ophthalmic disease or very high refractive error were excluded. Those exceeding the AAPOS 2003 Criteria (> + 3.5D spherical equivalent (SE), > 1.5D astigmatism, > 1.5D anisometropia) were randomized into wearing glasses or not, and are followed-up by research orthoptists. Other children are followed-up by regular vision screening at CHCs and visual acuity is measured in all children at age 4. Results Parents of 865 children were called, 123 were excluded. Of 742 children enrolled, 601 underwent the entry orthoptic examination at age 14.5 ± 1.7 months. Mean SE was + 1.73 ± 1.18D, astigmatism -0.70 ± 0.44D, anisometropia 0.21D (IQR: 0–0.25). Of 62 (10.3%) children exceeding the Criteria, 52 were randomized into wearing glasses or not. Of 539 other children, 522 are followed up at CHCs. In total, 31 were excluded: 2 had strabismus and amblyopia, 7 strabismus, 2 amblyopia suspect, 1 strabismus suspect, 1 squinting during sinusitis, 4 excessive refractive error, 9 myopia, 2 ptosis, 1 oculomotor apraxia, 1 Duane syndrome, 1 congenital nystagmus. Conclusion Prevalence of strabismus (10/601) was as expected, but prevalence of amblyopia (2/601) was low, suggesting that common amblyopia develops later than generally thought. Key messages What is known High refractive errors cause amblyopia, but no study has determined the exact relationship between the kind and size of refractive error at age 1 and the risk to develop amblyopia, and assessed the protective effect of glasses in a controlled, population-based, longitudinal study. What is new At baseline, 601 children received a full orthoptic examination followed by retinoscopy in cycloplegia at the age of 14.5 ± 1.7 months; 10.3% had high refractive error exceeding spherical equivalent > + 3.5D, > 1.5D astigmatism, > 1D oblique astigmatism or > 1.5D anisometropia. The prevalence of amblyopia was lower (0.3%) than expected, suggesting that most amblyopia develops after the first year of life. The prevalence of anisometropia, associated with amblyopia in older children, was low (0.8%).
SWOT analysis of the models used by social enterprises in scaling effective refractive error coverage to achieve the 2030 in SIGHT in Kenya
Uncorrected refractive error has predominantly been delivered through commercial entrepreneurship in Kenya. However, to achieve the 2030 IN SIGHT, integration of other forms of entrepreneurship such as the social entrepreneurship is desirable to supplement the efforts of the dominant commercial entrepreneurship. Therefore, this study intended to undertake a SWOT analysis of the current models used by social enterprises in scaling effective refractive error coverage to achieve the 2030 IN SIGHT in Kenya. A review of the seven national strategic plans for eye health in Kenya was undertaken to get a glimpse on the efforts directed towards uncorrected refractive error in achieving the 2030 IN SIGHT. The review was inclined towards assessing the efforts directed by the strategic plans towards scaling human resource, spectacle provision and refraction points. A SWOT analysis was undertaken based on the financial, impact and the approach report for each model. A key informant interview was conducted with a representative and three to five members of the social enterprise about the model. Thereafter, the modified SWOT analysis based on the review and the interview was presented to the representatives of the social enterprises. Purposive sampling was used to identify seven models used by social enterprises in the delivery of refractive error services in Kenya. Finally, the recommendations were presented to key opinion leaders for an input through a Delphi technique. Out of the seven national strategic plans for eye health reviewed, only the strategic plan 2020–2025 intends to establish optical units within 15 different counties in Kenya. Of the seven models currently utilized by social enterprises, only the Kenya Society for the Blind has integrated the telemedicine concept. On application of mHealth, all of the social enterprises models tend to embrace the approach for screening activities. None of the models has a strengthened referral pathway utilizing telereferral and telemedicine. Out of all the models, only Operation Eyesight Universal, Fred Hollow Foundation and Peek Acuity do not depend on sales of subsidized spectacles for sustainability. Every model has the capacity to propel the delivery of refractive error services depending on its comprehensiveness. However, for the 2030 IN SIGHT to be achieved, models prioritizing human resource through telemedicine integration, service provision across all sectors, awareness creation and enhancing cost efficiency are desirable.
Prevalence of refractive error in Europe: the European Eye Epidemiology (E3) Consortium
To estimate the prevalence of refractive error in adults across Europe. Refractive data (mean spherical equivalent) collected between 1990 and 2013 from fifteen population-based cohort and cross-sectional studies of the European Eye Epidemiology (E3) Consortium were combined in a random effects meta-analysis stratified by 5-year age intervals and gender. Participants were excluded if they were identified as having had cataract surgery, retinal detachment, refractive surgery or other factors that might influence refraction. Estimates of refractive error prevalence were obtained including the following classifications: myopia B-0.75 diopters (D), high myopia B-6D, hyperopia C1D and astigmatism C1D. Meta-analysis of refractive error was performed for 61,946 individuals from fifteen studies with median age ranging from 44 to 81 and minimal ethnic variation (98 % European ancestry). The age-standardised prevalences (using the 2010 European Standard Population, limited to those C25 and\\90 years old) were: myopia 30.6 % [95 % confidence interval (CI) 30.4–30.9], high myopia 2.7 % (95 % CI 2.69–2.73), hyperopia 25.2 % (95 % CI 25.0–25.4) and astigmatism 23.9 % (95 % CI 23.7–24.1). Age-specific estimates revealed a high prevalence of myopia in younger participants [47.2 % (CI 41.8–52.5) in 25–29 years-olds]. Refractive error affects just over a half of European adults. The greatest burden of refractive error is due to myopia, with high prevalence rates in young adults. Using the 2010 European population estimates, we estimate there are 227.2 million people with myopia across Europe.
Treatment coverage rates for refractive error in the National Eye Health survey
To present treatment coverage rates and risk factors associated with uncorrected refractive error in Australia. Thirty population clusters were randomly selected from all geographic remoteness strata in Australia to provide samples of 1738 Indigenous Australians aged 40 years and older and 3098 non-Indigenous Australians aged 50 years and older. Presenting visual acuity was measured and those with vision loss (worse than 6/12) underwent pinhole testing and hand-held auto-refraction. Participants whose corrected visual acuity improved to be 6/12 or better were assigned as having uncorrected refractive error as the main cause of vision loss. The treatment coverage rates of refractive error were calculated (proportion of participants with refractive error that had distance correction and presenting visual acuity better than 6/12), and risk factor analysis for refractive correction was performed. The refractive error treatment coverage rate in Indigenous Australians of 82.2% (95% CI 78.6-85.3) was significantly lower than in non-Indigenous Australians (93.5%, 92.0-94.8) (Odds ratio [OR] 0.51, 0.35-0.75). In Indigenous participants, remoteness (OR 0.41, 0.19-0.89 and OR 0.55, 0.35-0.85 in Outer Regional and Very Remote areas, respectively), having never undergone an eye examination (OR 0.08, 0.02-0.43) and having consulted a health worker other than an optometrist or ophthalmologist (OR 0.30, 0.11-0.84) were risk factors for low coverage. On the other hand, speaking English was a protective factor (OR 2.72, 1.13-6.45) for treatment of refractive error. Compared to non-Indigenous Australians who had an eye examination within one year, participants who had not undergone an eye examination within the past five years (OR 0.08, 0.03-0.21) or had never been examined (OR 0.05, 0.10-0.23) had lower coverage. Interventions that increase integrated optometry services in regional and remote Indigenous communities may improve the treatment coverage rate of refractive error. Increasing refractive error treatment coverage rates in both Indigenous and non-Indigenous Australians through at least five-yearly eye examinations and the provision of affordable spectacles will significantly reduce the national burden of vision loss in Australia.
Genome-wide association meta-analysis highlights light-induced signaling as a driver for refractive error
Refractive errors, including myopia, are the most frequent eye disorders worldwide and an increasingly common cause of blindness. This genome-wide association meta-analysis in 160,420 participants and replication in 95,505 participants increased the number of established independent signals from 37 to 161 and showed high genetic correlation between Europeans and Asians (>0.78). Expression experiments and comprehensive in silico analyses identified retinal cell physiology and light processing as prominent mechanisms, and also identified functional contributions to refractive-error development in all cell types of the neurosensory retina, retinal pigment epithelium, vascular endothelium and extracellular matrix. Newly identified genes implicate novel mechanisms such as rod-and-cone bipolar synaptic neurotransmission, anterior-segment morphology and angiogenesis. Thirty-one loci resided in or near regions transcribing small RNAs, thus suggesting a role for post-transcriptional regulation. Our results support the notion that refractive errors are caused by a light-dependent retina-to-sclera signaling cascade and delineate potential pathobiological molecular drivers. Transancestral GWAS meta-analysis in 160,420 individuals identifies 139 loci associated with refractive error, including myopia. Newly identified genes implicate pathways involved in eye growth and light signaling cascades.
Situation analysis of the social enterprises engaged in refractive error services delivery in Kenya
Aim To conduct a situational analysis of the social enterprises (SEs) engaged in refractive error services delivery in Kenya. Methods This was a sequential mixed method study conducted with commercial enterprises (CE), eye care professional’s representatives from the Ministry of Health ophthalmic service unit and representatives from SEs. The study was undertaken in two phases with phase one aimed at identifying the SEs while phase two aimed at exploring the SEs. The participants were recruited purposively and through snowball sampling with data collected telephonically and through online Google form survey. The qualitative data was collected until thematic saturation was achieved. The descriptive data was presented in figures, as well as reported in terms of frequencies. Results Out of the 196 (28%) CE, only 49 (7.1%) reported referral and vision screening as some of the support they provide to SEs. The key barrier to SE integration into refractive error service delivery in conjunction with other eye care providers in Kenya, was lack of awareness on SE ( n  = 12; 41.4%) while cash flow was noted as the least cited barrier to SEs integration ( n  = 2; 13.8%). Reasons for the success of SE in the broader eye health ecosystem constituted mission, leadership skills and creativity. Policy regulation reported by the SE representatives ( n  = 14; 48.3%) was the key factor influencing the operations of SEs in Kenya. Factors negatively influencing integration of SE into refractive error service delivery in Kenya were categorized into unhealthy competition, inadequate human resources, predator SE ( n  = 19; 65.5%) and lack of proper policy regulation. Partnership, technology, cross-subsidization and skills development were identified as ideal for SE integration. Conclusion This study found that SEs are worthy for integration into the eye health ecosystem to complement the dominant CE for effective refractive error service delivery. However, establishment of policies recognizing SEs and integration into the eye health ecosystem is desirable to address the challenges experienced by the SEs.
Cluster-randomized controlled trial of the effects of free glasses on purchase of children's glasses in China: The PRICE (Potentiating Rural Investment in Children's Eyecare) study
Offering free glasses can be important to increase children's wear. We sought to assess whether \"Upgrade glasses\" could avoid reduced glasses sales when offering free glasses to children in China. In this cluster-randomized, controlled trial, children with uncorrected visual acuity (VA)< = 6/12 in either eye correctable to >6/12 in both eyes at 138 randomly-selected primary schools in 9 counties in Guangdong and Yunnan provinces, China, were randomized by school to one of four groups: glasses prescription only (Control); Free Glasses; Free Glasses + offer of $15 Upgrade Glasses; Free Glasses + offer of $30 Upgrade Glasses. Spectacle purchase (main outcome) was assessed 6 months after randomization. Among 10,234 children screened, 882 (8.62%, mean age 10.6 years, 45.5% boys) were eligible and randomized: 257 (29.1%) at 37 schools to Control; 253 (28.7%) at 32 schools to Free Glasses; 187 (21.2%) at 31 schools to Free Glasses + $15 Upgrade; and 185 (21.0%) at 27 schools to Free Glasses +$30 Upgrade. Baseline ownership among these children needing glasses was 11.8% (104/882), and 867 (98.3%) children completed follow-up. Glasses purchase was significantly less likely when free glasses were given: Control: 59/250 = 23.6%; Free glasses: 32/252 = 12.7%, P = 0.010. Offering Upgrade Glasses eliminated this difference: Free + $15 Upgrade: 39/183 = 21.3%, multiple regression relative risk (RR) 0.90 (0.56-1.43), P = 0.65; Free + $30 Upgrade: 38/182 = 20.9%, RR 0.91 (0.59, 1.42), P = 0.69. Upgrade glasses can prevent reductions in glasses purchase when free spectacles are provided, providing important program income. ClinicalTrials.gov Identifier: NCT02231606. Registered on 31 August 2014.
Global estimates on the number of people blind or visually impaired by Uncorrected Refractive Error: a meta-analysis from 2000 to 2020
Background Uncorrected refractive error (URE) is a readily treatable cause of visual impairment (VI). This study provides updated estimates of global and regional vision loss due to URE, presenting temporal change for VISION 2020 Methods Data from population-based eye disease surveys from 1980–2018 were collected. Hierarchical models estimated prevalence (95% uncertainty intervals [UI]) of blindness (presenting visual acuity (VA) < 3/60) and moderate-to-severe vision impairment (MSVI; 3/60 ≤ presenting VA < 6/18) caused by URE, stratified by age, sex, region, and year. Near VI prevalence from uncorrected presbyopia was defined as presenting near VA < N6/N8 at 40 cm when best-corrected distance (VA ≥ 6/12). Results In 2020, 3.7 million people (95%UI 3.10–4.29) were blind and 157 million (140–176) had MSVI due to URE, a 21.8% increase in blindness and 72.0% increase in MSVI since 2000. Age-standardised prevalence of URE blindness and MSVI decreased by 30.5% (30.7–30.3) and 2.4% (2.6–2.2) respectively during this time. In 2020, South Asia GBD super-region had the highest 50+ years age-standardised URE blindness (0.33% (0.26–0.40%)) and MSVI (10.3% (8.82–12.10%)) rates. The age-standardized ratio of women to men for URE blindness was 1.05:1.00 in 2020 and 1.03:1.00 in 2000. An estimated 419 million (295–562) people 50+ had near VI from uncorrected presbyopia, a +75.3% (74.6–76.0) increase from 2000 Conclusions The number of cases of VI from URE substantively grew, even as age-standardised prevalence fell, since 2000, with a continued disproportionate burden by region and sex. Global population ageing will increase this burden, highlighting urgent need for novel approaches to refractive service delivery.
Screening-detected refractive errors in infants born after assisted reproductive technology: a prospective cohort study
Purpose Infants born after assisted reproductive technology (ART) have more adverse health outcomes than spontaneously conceived infants. Evidence on the impact of ART on the offspring’s visual system, particularly refractive errors (REs), remains limited and inconsistent. Methods The present study included 6847 infants from the Jiangsu Birth Cohort (JBC), which enrolled couples who conceived either through ART or spontaneously between 2015 and 2022 in Jiangsu Province, China. ART procedures and parental characteristics were collected prospectively, and REs were assessed at one year of age using the Spot Vision Screener. Poisson regression models were used to examine the association between ART and screening-detected REs. Results Screening-detected REs were identified in 369 infants born after ART (11.4%) and in 405 infants spontaneously conceived (11.2%). No overall association was observed between ART and the risk of REs (RR, 0.91; 95% CI 0.77–1.07). Infants born to parents with different infertility diagnoses or following specific ART procedures had similar risks of REs compared with spontaneously conceived infants. In the analyses restricted to ART-conceived infants, infants conceived using the gonadotropin-releasing hormone antagonist (GnRH-antagonist) protocol had a lower risk of REs (RR, 0.56; 95% CI 0.44–0.71) compared with those using the gonadotropin-releasing hormone agonist (GnRH-agonist) protocol. Conclusion We observed no increased risk of screening-detected REs at one year of age in ART-conceived infants compared with spontaneously conceived infants, independent of parental infertility diagnoses or specific ART procedures. Among the ART-conceived infants, the use of the GnRH-antagonist protocol may be associated with a lower risk of screening-detected REs; however, this finding should be interpreted cautiously because protocol selection was clinically guided and residual confounding cannot be excluded.