Risk factors for astigmatism in the Vision in Preschoolers Study

Prevalence and risk factors for astigmatism in 7 to 19-year-old students in Xinjiang, China: a cross-sectional study

BACKGROUND

To investigate the prevalence and risk factors for astigmatism in 7-19-year-old students in Xinjiang, China.

METHODS

A school-based, cross-sectional study was conducted on students who underwent refraction examination in Xinjiang, China, between May and December 2019. The prevalence of astigmatism was determined. Astigmatism was defined as cylinder power (C) ≤-0.75 D, undefined astigmatism as ≤-1.50 D, and high astigmatism as C ≤-3.00 D. Astigmatism types were: against-the-rule astigmatism (maximum refraction of the main meridian in 180° ± 30°), with-the-rule astigmatism (maximum refraction of the main meridian at 90°±30°), and oblique astigmatism (all other cases).

RESULTS

Of the 71,838 students examined (51.0% boys, 7 - 19 years old), 25,945 (36.1%, 95%CI: 35.52-36.68%) had astigmatism and 1267 (1.8%, 95%CI: 1.07-2.53%) had high astigmatism. The prevalence of astigmatism was greater in Han individuals (39.6%) compared with the Hui (34.0%), Kazakh (34.0%), Kyrgyz (32.1%), and Uyghur (26.4%) populations. Among the 25,945 students with astigmatism, 19,947 had with-the-rule astigmatism (76.9%), 3405 had against-the-rule astigmatism (13.1%), and 2593 had oblique astigmatism (10.0%). Multivariable logistic regression analysis showed that ethnicity (Han individuals more susceptible), male gender, age, and refractive errors (myopia and hyperopia) were independently associated with astigmatism, high astigmatism, and with-the-rule astigmatism (all P < 0.05).

CONCLUSIONS

The prevalence of astigmatism among children and adolescents in Xinjiang was 36.1%, including 1.8% of high astigmatism. In this population, astigmatism was mainly of the with-the-rule astigmatism type (76.9%). Han ethnicity, male gender, and myopia or hyperopia were independently associated with a high risk of astigmatism.

Refractive and corneal astigmatism in Chinese 4-15 years old children: prevalence and risk factors

BACKGROUND

To investigate the prevalence and risk factors of refractive astigmatism (RA) and corneal astigmatism (CA) in preschool children and school-aged children in Shanghai, China.

METHODS

In this school-based, cross-sectional study, 4-15 years old children across three learning stages of kindergarten, primary school, and junior high school underwent noncycloplegic autorefraction and completed comprehensive questionnaires involving time spent on daily homework and outdoor activities. Data from the right eyes were analysed.

RESULTS

Overall, 7084 children (mean ± standard deviation (SD) of age: 8.08 ± 3.11 years) were included, and the prevalence rates of RA/CA ( ≤ - 1.0 D) in children were 15.8%/64% in kindergartens, 16.5%/65% in primary schools, and 32.8%/76.9% in junior high schools. The magnitude and prevalence of RA and CA all increased with age or with learning stage (all P < 0.001). The presence of RA was associated with more myopic spherical power (odds ratio (OR) 0.956, P = 0.021), junior high school (OR 1.973, P < 0.001), longer homework time on weekdays (OR 1.074, P = 0.029), and shorter outdoor activity time on weekends (odds ratio 0.929, P = 0.013).

CONCLUSION

In the wide age range of 4 to 15 years, the magnitude and prevalence of RA and CA increased with the learning stage, and these increases mainly began at the primary school stage. Factors, including longer homework time and shorter outdoor time were correlated with the presence of RA.

[Influence of tropical endemic limboconjunctivitis on the distribution of astigmatism in a black pediatric population: A hospital-based case-control study]

PURPOSE

To study the influence of tropical endemic limboconjunctivitis (TELC) on the distribution of astigmatism in a population of black children.

PATIENTS AND METHODS

We matched two groups of 36 children between the ages of 3 and 15 by age and sex. Group 1 consisted of children with TELC, and group 2 was made up of controls. All underwent cycloplegic refraction. The studied variables were age, sex, type and stage of TELC, spherical equivalent, absolute cylinder value and clinical type of astigmatism. The odds ratio was used to quantify the link between TELC and astigmatism. We used the Chi2 test for the comparison of qualitative variables and the Student T test for the comparison of the means of quantitative variables. The threshold of significance of the differences was set at 0.05.

RESULTS

Astigmatism was more common in children with TELC (61.97% vs. 37.5%), (OR=1.53; 95% CI 1.08-2.15; P=0.012). The history of TELC was associated with an increased risk of with-the-rule astigmatism (OR 1.91; 95%CI (1.23-2.97).

CONCLUSION

Pediatric TELC is frequently associated with the with-the-rule astigmatism in our practice setting.

Characteristics of full compensation and its association with total astigmatism: A cross-sectional study

Objective

To evaluate the characteristics of full compensation and its association with the prevalence of total astigmatism (TA), and to analyze the effects of TA on uncorrected distance visual acuity (UDVA).

Methods

With random cluster sampling based on a school-based cross-sectional design, children aged 4 to 18 years were recruited in September 2020, Shandong Province, China. TA, anterior corneal astigmatism (ACA), and ocular residual astigmatism (ORA) were converted to vectorial components (J0, J45), followed by an assessment of the compensatory effect of ACA by ORA. Astigmatism was defined as a cylinder that was better than or equal to 0.75 diopters (D). Logistic regression analysis was used to assess the related factors for children with full compensation, and the generalized linear model was used to assess the influence of TA on UDVA.

Results

Out of 4,494 eligible children, data of 4,145 children (92.3%, 9.23 ± 3.15 years, 50.4% boys) were included in the statistical analysis. The prevalence of TA (27.9%) increased significantly with age (P_trend < 0.001). The distribution of full compensation in J0 and J45 components were similar (22.1% and 25.6%, respectively), which decreased with age (P_trend < 0.001). The closer the refractive status was to emmetropization, the higher the proportion of full compensation and the lower the prevalence of TA were. Shorter axial length (J0: Odds Ratio (OR) = 0.76, 95% confidence interval (CI): 0.61 to 0.94, P = 0.010), better UDVA (J0: OR = 0.37, 95% CI: 0.21 to 0.65, P < 0.001; J45: OR = 0.34, 95% CI: 0.20 to 0.59, P < 0.001), and longer average corneal curvature radius (J0: OR = 3.72, 95% CI: 2.18 to 6.34, P < 0.001; J45: OR = 2.82, 95% CI: 1.67 to 4.76, P < 0.001) were associated with full compensation. Higher TA was associated with a worse UDVA (β = 0.03, 95% CI: 0.02 to 0.04, P < 0.001).

Conclusions

The prevalence of TA gradually increased with age, and showed a U-shaped distribution with increased refraction. Full compensation was associated with smaller TA and better UDVA. This indicated that considering the compensatory effect of ORA is vital for astigmatism correction in clinical work, which may improve the visual quality.

Cost-effectiveness of Universal School- and Community-Based Vision Testing Strategies to Detect Amblyopia in Children in Ontario, Canada

IMPORTANCE

Screening for amblyopia in primary care visits is recommended for young children, yet screening rates are poor. Although the prevalence of amblyopia is low (3%-5%) among young children, universal screening in schools and mandatory optometric examinations may improve vision care, but the cost-effectiveness of these vision testing strategies compared with the standard in primary care is unknown.

OBJECTIVE

To evaluate the relative cost-effectiveness of universal school screening and mandated optometric examinations compared with standard care vision screening in primary care visits in Toronto, Canada, with the aim of detecting and facilitating treatment of amblyopia and amblyopia risk factors from the Ontario government's perspective.

DESIGN, SETTING, AND PARTICIPANTS

An economic evaluation was conducted from July 2019 to May 2021 using a Markov model to compare 15-year costs and quality-adjusted life-years (QALYs) between school screening and optometric examination compared with primary care screening in Toronto, Canada. Parameters were derived from published literature, the Ontario Schedule of Benefits and Fees, and the Kindergarten Vision Testing Program. A hypothetical cohort of 25 000 children aged 3 to 5 years was simulated. It was assumed that children in the cohort had irreversible vision impairment if not diagnosed by an optometrist. In addition, incremental costs and outcomes of 0 were adjusted to favor the reference strategy. Vision testing programs were designed to detect amblyopia and amblyopia risk factors.

MAIN OUTCOMES AND MEASURES

For each strategy, the mean costs per child included the costs of screening, optometric examinations, and treatment. The mean health benefits (QALYs) gained were informed by the presence of vision impairment and the benefits of treatment. Incremental cost-effectiveness ratios were calculated for each alternative strategy relative to the standard primary care screening strategy as the additional cost required to achieve an additional QALY at a willingness-to-pay threshold of $50 000 Canadian dollars (CAD) ($37 690) per QALY gained.

RESULTS

School screening relative to primary care screening yielded cost savings of CAD $84.09 (95% CI, CAD $82.22-$85.95) (US $63.38 [95% CI, US $61.97-$64.78]) per child and an incremental gain of 0.0004 (95% CI, -0.0047 to 0.0055) QALYs per child. Optometric examinations relative to primary care screening yielded cost savings of CAD $74.47 (95% CI, CAD $72.90-$76.03) (US $56.13 [95% CI, $54.95-$57.30]) per child and an incremental gain of 0.0508 (95% CI, 0.0455-0.0561) QALYs per child. At a willingness-to-pay threshold of CAD $50 000 (US $37 690) per QALY gained, school screening and optometric examinations were cost-effective relative to primary care screening in only 20% and 29% of iterations, respectively.

CONCLUSIONS AND RELEVANCE

In this study, because amblyopia prevalence is low among young children and most children in the hypothetical cohort had healthy vision, universal school screening and optometric examinations were not cost-effective relative to primary care screening for detecting amblyopia in young children in Toronto, Canada. The mean added health benefits of school screening and optometric examinations compared with primary care screening did not warrant the resources used.

Association of Maternal and Paternal Astigmatism With Child Astigmatism in the Hong Kong Children Eye Study

IMPORTANCE

Parental astigmatism is a factor associated with risk for development of child astigmatism; however, the magnitude of the association has not been determined.

OBJECTIVE

To determine the association between parental and child astigmatism.

DESIGN, SETTING, AND PARTICIPANTS

This population-based, cross-sectional study included participants from familial trios, each comprising a child aged 6 to 8 years and both parents, recruited from the Hong Kong Children Eye Study. No restriction criteria were set on the children in terms of refractive status. Data were analyzed from February to June 2022.

EXPOSURES

Cycloplegic autorefraction and autokeratometry were conducted on the children, whereas noncycloplegic autorefraction and autokeratometry were conducted on their parents. The children were categorized into 6 groups on the basis of the severity of astigmatism of both parents. Information on parental education, family income, and children's outdoor and near work time were obtained by questionnaires.

MAIN OUTCOMES AND MEASURES

The primary outcome was the odds of child astigmatism among the 6 categories of children. Associations of factors with child astigmatism were evaluated by logistic regression analyses.

RESULTS

A total of 17 124 participants from 5708 trios (2964 boys and 2754 girls) at a mean (SD) age of 7.32 (0.87) years, and 11 416 parents were examined. Astigmatism of 1.0 D or greater in both parents was associated with greater odds of refractive astigmatism (RA) (odds ratio [OR], 1.62; 95% CI, 1.15-2.26) and corneal astigmatism (CA) (OR, 1.94; 95% CI, 1.50-2.50) in the child. The respective ORs increased to 3.10 (95% CI, 1.34-7.21) and 4.31 (95% CI, 1.76-10.55) when both parents had astigmatism 2.0 D or greater. Higher parental astigmatism conferred higher risks for both RA and CA in children (P for trend <.001). Parental astigmatism was significantly associated with greater odds of corresponding child astigmatism (maternal RA: OR, 0.76; 95% CI, 0.68-0.84; paternal RA: OR, 0.82; 95% CI, 0.74-0.91; maternal CA: OR, 1.70; 95% CI, 1.51-1.93; paternal CA: OR, 1.33; 95% CI, 1.19-1.49).

CONCLUSIONS AND RELEVANCE

The findings of this cross-sectional study suggest that parental astigmatism may confer an independent and dose-dependent association with child astigmatism. Children with parents with astigmatism should have early eye examinations for timely detection of astigmatism to facilitate age-appropriate vision correction and visual development.

High Prevalence of Astigmatism in Children after School Suspension during the COVID-19 Pandemic Is Associated with Axial Elongation

During the COVID-19 pandemic, the Hong Kong Government enforced a “school from home” policy between February and September 2020. This cross-sectional epidemiological study was conducted to investigate the prevalence of astigmatism and visual habits after the home confinement period. Vision screenings were conducted at three local government-funded primary schools in Hong Kong from October 2020 to December 2020. A total of 418 ethnically Chinese primary school children completed the eye examination and returned questionnaires concerning demographic information and visual habits. It was found that 46.5% (95% CI, 41.7−61.4%) of the children aged 8 to 11 years had astigmatism ≥ 0.75 D, which was predominately With-The-Rule astigmatism. The prevalence of astigmatism reported in these children is generally higher than that of studies conducted before COVID. Compared to their non-astigmatic peers, astigmatic children had a longer axial length (p < 0.001) and engaged in fewer outdoor activities (p = 0.04). Multiple linear regression analyses also revealed significant relationships between axial length and both cylindrical error and J0 astigmatism. Due to the high astigmatism prevalence, there is a pressing need for further studies on the long-term impact of the pandemic on children’s vision.

Association of Physical Activity and Sedentary Behaviors with the Risk of Refractive Error in Chinese Urban/Rural Boys and Girls

Background: Research shows physical activity (PA) is negatively associated with refractive error, especially outdoor activity. Our study aimed to examine the association of PA levels and sedentary time (SED) with refractive error in boys and girls living in urban and rural areas. Methods: A total of 8506 urban/rural boys and girls (13.5 ± 2.8 years old) in Shaanxi Province, China participated in this study. Questions about PA, SED, outdoor exercises, and digital screen time were asked in the study survey. Non-cycloplegic refractive error was measured by an autorefractor. The differences between sex/area groups have been analyzed by one-way ANOVA. The association of PA/SED with spherical equivalent (SE) and cylinder power was analyzed by general linear regression. The association between PA/SED and the risk of refractive error was determined using the binary logistic regression model. Results: Of the 8506 participants, the prevalence of refractive error was significantly higher in girls and urban students (p < 0.05). Less SED and digital screen time, and more outdoor activity were significantly associated with SE (p < 0.05), respectively. More PA and less SED were significantly associated with lower cylinder power (p < 0.05), respectively. More PA and less SED were significantly associated with lower risks of myopia and astigmatism, respectively (p < 0.05). Conclusions: PA and SED were associated with the risk of refractive error. Maintaining a healthy lifestyle can help to reduce the risk of refractive error in boys and girls.

Effect of Parental Myopia on Change in Refraction in Shanghai Preschoolers: A 1-Year Prospective Study

Background

To investigate the risk factors for change in refraction and refractive components in preschoolers.

Methods

Preschool children aged 3-5 years old, from the junior and the middle grades of seven randomly selected kindergartens in Jia Ding District, Shanghai, were followed for 1 year. Cycloplegic autorefraction (1% cyclopentolate) and axial length (AL) were measured at baseline and at 1-year follow-up. Questionnaires about parental myopia and environmental risk factors, such as time of outdoors and near work, were collected.

Results

A total of 603 right eyes of 603 children were included. Parental myopia was not associated with a change in refraction, but two myopic parents were associated with a longer change in AL (coefficient = 0.153, p = 0.006), after adjusted for baseline spherical refraction, age, gender, change in height, change in weight, and environment risk factors. In the multivariate analyses, boys showed a more myopic refraction shift than girls in 1 year (coefficient = -0.150, p = 0.008) and a quicker AL elongation (coefficient = 0.120, p = 0.008). Time of near work, such as watching television, using computer, reading and writing, and time of outdoor activities, was not associated with a change in refraction or AL.

Conclusions

In preschool age, environmental risk factors were not strongly associated with the change in refraction or refractive components. Parental myopia influences the refractive development of children continuously from infancy to preschool age, which might be the biological basis of school myopia.

Prevalence of and factors associated with astigmatism in preschool children in Wuxi City, China

PURPOSE

To investigate the status of astigmatism in preschool children in Wuxi City, and explore the risk factors related to astigmatism. The risk factors related to astigmatism development as predictors can help us identify preschool children who need vision screening at an early stage to ensure good visual quality.

METHODS

The cross-sectional study was conducted in 10 kindergartens randomly selected in five districts of Wuxi City in November 2018. All preschool children were measured by objective refractometry under non-cycloplegic refraction. The basic information of preschool children was collected. The relevant factors of astigmatism in the questionnaire were completed by parents. Spss 26. 0 software was used for univariate and multivariate correlation analysis.

RESULTS

A total of 889 preschool children participated in the study, 864 were finally included in the study. The prevalence of astigmatism was 36.0%. The risk of astigmatism in premature children was higher than that in non-premature children (adjusted odds ratio = 1.841). The prevalence of astigmatism with parents' astigmatism history was higher, compared with preschool children without parents' astigmatism history (adjusted odds ratio = 2.037). When maternal age at childbirth was older (≥ 35 years old), the risk of astigmatism increased in preschool children (adjusted odds ratio = 2.181). Compared with bottle feeding, the risk of astigmatism for mixed feeding and breastfeeding reduced in preschool children. Compared with preschool children exposed to electronic screen for less than 2 h every day, preschool children exposed to electronic screen for more than 2 h had an increased risk of astigmatism (P = 0.004).

CONCLUSION

The prevalence of astigmatism among preschool children in Wuxi City was high. Some risk factors such as premature birth, parents' astigmatism history, maternal age at childbirth, feeding pattern, and electronic screen exposure time were closely related to the occurrence of astigmatism among preschool children. For preschool children with significant risk factors, their eyesight should be checked regularly to ensure their visual quality.

Vision Screening, Vision Disorders, and Impacts of Hyperopia in Young Children: Outcomes of the Vision in Preschoolers (VIP) and Vision in Preschoolers - Hyperopia in Preschoolers (VIP-HIP) Studies

ABSTRACT

This review summarizes clinically relevant outcomes from the Vision in Preschoolers (VIP) and VIP-Hyperopia in Preschoolers (VIP-HIP) studies. In VIP, refraction tests (retinoscopy, Retinomax, SureSight) and Lea Symbols Visual Acuity performed best in identifying children with vision disorders. For lay screeners, Lea Symbols single, crowded visual acuity (VA) testing (VIP, 5-foot) was significantly better than linear, crowded testing (10-foot). Children unable to perform the tests (<2%) were more likely to have vision disorders than children who passed and should be referred for vision evaluation. Among racial/ethnic groups, the prevalence of amblyopia and strabismus was similar while that of hyperopia, astigmatism, and anisometropia varied. The presence of strabismus and significant refractive errors were risk factors for unilateral amblyopia, while bilateral astigmatism and bilateral hyperopia were risk factors for bilateral amblyopia. A greater risk of astigmatism was associated with Hispanic, African American, and Asian race, and myopic and hyperopic refractive error. The presence and severity of hyperopia were associated with higher rates of amblyopia, strabismus, and other associated refractive error. In the VIP-HIP study, compared to emmetropes, meaningful deficits in early literacy were observed in uncorrected hyperopic 4- and 5-year-olds [≥+4.0 diopter (D) or ≥+3.0 D to ≤+6.0 D associated with reduced near visual function (near VA 20/40 or worse; stereoacuity worse than 240")]. Hyperopia with reduced near visual function also was associated with attention deficits. Compared to emmetropic children, VA (distance, near), accommodative accuracy, and stereoacuity were significantly reduced in moderate hyperopes, with the greatest risk in those with higher hyperopia. Increasing hyperopia was associated with decreasing visual function.

Effectiveness of citicoline in pediatric patients with refractive amblyopia in Surabaya, East Java, Indonesia

OBJECTIVES

Amblyopia is a decrease of visual acuity that cannot be attributed to any structural abnormality of the eye or visual system, causing a partial or complete loss of vision due to inadequate stimulation in early life. Citicoline has been reported to improve visual acuity in amblyopic eyes as adjuvant treatment. This study was aimed to determine the effectiveness of citicoline in pediatric patients with refractive amblyopia in ophthalmology daily practices.

METHODS

This was a retrospective-descriptive study with a time limited sampling method. This study was conducted at Surabaya Eye Clinic, East Java, Indonesia, by reviewing medical records for the period of January 2018 to December 2019.

RESULTS

A total of 34 eyes were included in the study with the majority aged five years (41.2%) and six years (35.3%). The severity of amblyopia varied among patients, 21 eyes (61.76%) had mild amblyopia, seven eyes (20.59%) had moderate amblyopia, and two eyes (5.88%) had severe amblyopia. The duration of given therapy also varied, 18 eyes (52.94%) were given 3 months therapy, two eyes were given 4 months therapy, 12 eyes were given 6 months therapy, and two eyes were given 8 months therapy. Citicoline was found effective in mild and moderate amblyopia and for the duration of 3 and 6 months (p<0.05). In others group who did not showed statistically significant improvement was due to inadequate samples but clinically significant improvement was noted.

CONCLUSIONS

Citicoline therapy resulted in a clinically and statistically improvement in refractive amblyopia patients.

Evidence-Based Clinical Practice Guideline: Comprehensive Pediatric Eye and Vision Examination

Republished with written permission granted from the American Optometric Association, October 2, 2020.

Feasibility of a school-based vision screening program to detect undiagnosed visual problems in kindergarten children in Ontario

BACKGROUND

Visual problems can negatively affect visual development and learning but often go undetected. We assessed the feasibility of scaling up a school-based screening program to identify and treat kindergarten children with visual problems.

METHODS

We conducted a prospective cohort study offering vision screening to junior (JK) and senior kindergarten (SK) children attending 43 schools in 15 Ontario communities. Screening comprised photoscreeners and tests of visual acuity, stereoacuity and eye alignment. Children who failed any test were referred for a comprehensive eye examination, with treatment as needed (e.g., glasses).

RESULTS

Using a passive consent model, 89% of children were screened compared with 62% using an active consent model (p < 0.001). Referral rates to an optometrist varied across schools (mean referral rate for children in JK 53%, range 25%-83%; mean referral rate for children in SK 34%, range 12%-61%). Among 4811 children who were screened, a visual problem was detected in 516 (10.7%), including 164 (3.4%) with amblyopia and 324 (6.7%) with clinically significant refractive errors. For 347 (67.2%) of the children with a visual problem, this was their first eye examination. Rescreening in Year 2 did not lead to detection of additional problems among children who passed screening in Year 1. Regardless of location (child's school or optometrist's office), 1563 (68.9%) of children attended the follow-up optometry examination. Most of the children who were surveyed (291 of 322, 90.4%) indicated that they enjoyed vision screening.

INTERPRETATION

Many children in Ontario with a visual problem were not being identified by the status quo in 2015-2017. We found that in-school vision screening with follow-up eye examinations is an effective strategy for identifying at-risk children and placing them in eye care before grade 1.

Relationship between Geography and Refractive Error from the UCLA Preschool Vision Program

PURPOSE

Using the screening data collected through the University of California, Los Angeles Preschool Vision Program (UPVP) that provides free vision screening to children 2.5 to 6 years of age attending public preschools in five Supervisory Districts in Los Angeles County, this paper explores whether geographic location of where children attended preschool affects the vision screening results.

METHODS

62,936 children were screened using a handheld device (Nikon Retinomax) between academic years 2012 and 2015. The criteria for failing the screening was set to sphere of ≤ -3.25 diopters (D), sphere ≥ +1.75 D, or cylinder of ≥1.50 D in either eye, or inter-ocular difference of >2.00 D in spherical error (>1.50D in case of antimetropia) or ≥1.00 D in cylinder error.

RESULTS

Higher fail rates were found among girls, Latino race, and those who primarily spoke Spanish at home. In addition, there was a geographical variance in screening outcomes among Supervisory Districts with District 1 having the highest fail rate and District 4 having the lowest fail rate.

CONCLUSION

This paper provides preliminary evidence of geographic factors contributing to the development of refractive errors among preschoolers which may be used in future studies to address the unmet needs of children with vision impairments in Los Angeles County.

Risk factors for astigmatic components and internal compensation: the Nanjing Eye Study

Purpose

To determine the risk factors for total astigmatism (TA), anterior corneal astigmatism (ACA), and internal compensation in Chinese preschool children.

Methods

In the population-based Nanjing Eye Study, children were measured for noncycloplegic refractive error and for biometric parameters. Data from questionnaires and measures from right eyes were analyzed for determining risk factors for TA, ACA, and internal compensation from multivariate logistic regression models.

Results

Of 1327 children (66.8 ± 3.4 months, 53.2% male), older age of the child (OR = 0.95 for per month increase; P = 0.03), older paternal age at child birth (OR = 1.04 for per year increase; P = 0.03), paternal astigmatism (OR = 1.89; P = 0.003), maternal astigmatism (OR = 1.73, P = 0.008), and second-hand smoke exposure during pregnancy (OR = 1.64; P = 0.03) were associated with higher risk of TA, while partial breastfeeding (OR = 0.49, P = 0.006) or formula feeding (OR = 0.46, P = 0.003) were associated with lower risk of TA. Larger ratio of axial length to corneal radius (OR = 16.16 for per unit increase; P = 0.001), maternal working during pregnancy (OR = 1.27; P = 0.04), and cesarean delivery (OR = 1.68, P = 0.04) were associated with higher risk of ACA, while formula feeding was associated with lower risk of ACA (OR = 0.57, P = 0.01). Paternal astigmatism (OR = 0.50, P = 0.01) and assisted reproduction (OR = 0.56, P = 0.03) were associated with lower risk of horizontal or vertical internal compensation. More outdoor activity time (OR = 1.15 for per hour increase, P = 0.01) was associated with higher risk of oblique internal compensation while more nighttime sleep on weekends (OR = 0.83 for per hour increase, P = 0.01) was associated with lower risk of oblique internal compensation.

Conclusions

Our study confirmed some previously reported risk factors and identified some novel risk factors for astigmatism including formula feeding for lower risk of both ACA and TA, and older paternal age at child birth for higher risk of TA.

Astigmatism in school students of eastern China: prevalence, type, severity and associated risk factors

BACKGROUND

China has been undergoing dramatic economic development, accompanied by increased education load on the young children. This study is to investigate the prevalence, type, severity, and associated risk factors of astigmatism in school students in eastern China.

METHOD

In this cross-sectional school-based study, students underwent refraction using NIDEK non-cycloplegic autorefractor. Astigmatism was defined as cylinder 1.5 diopter (D) or greater, and high astigmatism was defined as cylinder 3.0 D or greaterMultivariate regression models were used to determine factors associated with astigmatism.

RESULTS

Among 4801 children (55% male) with mean age (±standard deviation) 12.3 (±3.8) years, 680 (14.2, 95% confidence interval (95% CI): 13.2-15.2%) had astigmatism (85% were with-the-rule) and 103 (2.2, 95% CI: 1.8-2.6%) had high astigmatism. The prevalence rate of astigmatism was 7-8% in grades 4 or below, 15-16% in grades 6-8, 20% in grade 9, and 20-25% in grade 10 or above. In multivariate analyses, higher grade and male gender were associated with higher prevalence of astigmatism (all p < 0.0001) and high astigmatism (p = 0.04 for grade, p = 0.001 for gender). When multivariate models were further adjusted by spherical equivalent, only gender remained statistically associated with astigmatism (odds ratio (OR) = 1.65, p < 0.0001) and high astigmatism (OR = 2.21, p = 0.0004), myopic and hyperopic refractive error were significantly associated with higher risk of astigmatism and high astigmatism (all p < 0.0001).

CONCLUSION

Astigmatism is common in Chinese school-age children and increases with grade. Majority of astigmatism is with-the-rule. Male gender and myopic or hyperopic refractive error are significantly associated with higher prevalence and severity of astigmatism.

Refractive Errors and Amblyopia Among Children Screened by the UCLA Preschool Vision Program in Los Angeles County

PURPOSE

To summarize the results of 5 years of vision screening with the University of California, Los Angeles (UCLA) Preschool Vision Program (UPVP).

DESIGN

Retrospective evaluation of a screening program.

METHODS

The UPVP performed visual acuity and undilated noncycloplegic refractive screening using an autorefractor on 93,097 children between 2012 and 2017. Of these, 79,451 children, who were between 3 and 5 years old, were screened for the first time, and 14,259 were referred for full cycloplegic examination if they met specific refractive criteria for myopia, hyperopia, astigmatism, or anisometropia. UPVP performed 6779 cycloplegic examinations on this population. Data from the right eye only were included in this analysis.

RESULTS

Of the examined population, hyperopia was found in 61% (4018), myopia in 20% (1336), and astigmatism in 93% (6122) of children. Latino children had higher rates of astigmatism and worse visual acuity compared to all other races/ethnicities. An astigmatism cutoff of ≥1.50 diopters (D) in either eye correctly predicted the need for glasses 93% of the time; increasing this cutoff to ≥1.50 D in both eyes increased the positive predictive value to 96%. Refractive amblyopia was found in 780 children (1.0% of the screened population and 11.5% of the examined population), and of these, 211 (27%) were bilaterally amblyopic.

CONCLUSIONS

These data represent the largest published sample of vision screening results on preschool-aged children, provide additional insight on the proportion of common refractive errors and their association with race/ethnicity, and can inform screening criteria to more accurately identify children who need intervention to prevent permanent vision loss.

Guide de pratique clinique fondé sur des données probantes pour l'examen périodique de la vue chez les enfants de 0 à 5 ans au Canada

CONTEXTE

Étant donné que les maladies oculaires avant l'âge de 5 ans sont courantes, une certaine forme de dépistage des troubles de la vision devrait être effectuée chez les enfants avant qu'ils ne fréquentent l'école primaire. Cependant, l'absence de recommandations nationales cohérentes crée de la confusion chez les patients, les professionnels des soins oculovisuels et les gouvernements. MéTHODES: L'objectif de ce document est de fournir des recommandations quant aux types d'examens oculaires à pratiquer chez les enfants en bonne santé de 0 à 5 ans ainsi que sur le moment et la périodicité de tels examens. Une recension des écrits a produit 403 articles. Un comité d'experts multidisciplinaire (composé de deux optométristes, d'un ophtalmologiste effectuant des examens complets de la vue, d'un ophtalmologiste pratiquant en pédiatrie, d'un médecin de famille et d'un pédiatre) a établi de façon indépendante les articles jugés essentiels à la question clinique. Les articles se prêtant à un classement [n = 16] ont ensuite été soumis à une évaluation critique indépendante par un groupe externe, lequel a fourni un profil « GRADE » des articles à utiliser et leur a attribué une cote.

RECOMMANDATIONS

En plus du dépistage de routine effectué par les professionnels de première ligne, un examen complet de la vue mené par un professionnel possédant l'expertise nécessaire à la détection des facteurs de risque de l'amblyopie (comme un ophtalmologiste ou un optométriste) est requis durant la petite enfance. Les conclusions confirment l'importance de la détection précoce de l'amblyopie avant 36 mois et au plus tard 48 mois par le dépistage assorti d'au moins un examen complet de la vue avant l'âge de 5 ans.

CONCLUSIONS

Le dépistage de la vue effectué chez les bébés et les enfants par les fournisseurs de soins de première ligne au cours des consultations de routine et des vaccinations périodiques est un élément essentiel de la détection des maladies oculaires. Toutefois, le potentiel de détection précoce est limité et un examen oculovisuel complet est également recommandé avant que l'enfant n'entre à l'école. Si l'amblyopie, le strabisme ou une autre pathologie oculaire est détecté ou soupçonné, et que le problème dépasse le champ de compétences du professionnel qui examine le patient, celui-ci peut être dirigé vers le spécialiste approprié, ce qui permet d'amorcer le traitement en temps opportun.

Evidence-based clinical practice guidelines for the periodic eye examination in children aged 0-5 years in Canada

BACKGROUND

As eye disease before age 5 years is common, some form of vision screening should be performed on children before attending primary school. However, the lack of consistent national recommendations creates confusion for patients, eye care professionals, and governments alike.

METHODS

The objective of this document is to provide guidance on the recommended timing, intervals, and types of ocular assessments for healthy children aged 0-5 years. A literature search yielded 403 articles. A multidisciplinary expert committee (comprising 2 optometrists, a comprehensive ophthalmologist, a pediatric ophthalmologist, a family physician, and a pediatrician) independently determined those articles deemed to be key to the clinical question. Articles that were gradable (n = 16) were then submitted for independent critical appraisal by an external review group, which provided a Grading of Recommendations Assessment, Development and Evaluation profile of the reviewed articles to use for assigning a grade of evidence.

RECOMMENDATIONS

In addition to routine screening by a primary health care professional, a comprehensive eye examination by an individual with the expertise to detect risk factors for amblyopia-such as an ophthalmologist or optometrist-is required in early childhood. The findings support the importance of early detection of amblyopia before 36 months and no later than 48 months of age via screening with at least 1 comprehensive eye examination before age 5 years.

CONCLUSIONS

Vision screening performed by primary health care providers during routine well-baby/child visits and scheduled vaccinations is an essential part of the detection of ocular disease. However, this early detection potential is limited, and a full oculovisual assessment is also recommended before the child entering the school system. If amblyopia, strabismus, or other eye pathology is detected or suspected that is beyond the scope of the eye care professional examining the patient, a referral to the appropriate specialist can be made, allowing treatment to be initiated in a timely fashion.

Choosing appropriate tools and referral criteria for vision screening of children aged 4-5 years in Canada: a quantitative analysis

OBJECTIVES

To assess the diagnostic accuracy of five vision screening tools used in a school setting using sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV).

DESIGN

We compared the results of the five best evidence-based screening tools available in 2014 to the results of a comprehensive eye exam with cycloplegic refraction by a licenced optometrist. Screening included Cambridge Crowded Acuity Cards, Plusoptix S12 and Spot photoscreeners, Preschool Randot Stereoacuity Test and the Pediatric Vision Scanner (PVS). Referral criteria followed AAPOS (2013) guidelines and published norms.

SETTING

A large school in Toronto, Canada, with 25 split classrooms of junior kindergarten (JK: 4 year olds) and senior kindergarten (SK: 5 year olds) children.

PARTICIPANTS

Over 2 years, 1132 eligible children were enrolled at the school. After obtaining parental consent, 832 children were screened. Subsequently, 709 children had complete screening and optometry exam data.

MAIN OUTCOME MEASURES

The presence/absence of a visual problem based on optometrist's assessment: amblyopia, amblyopia risk factors (reduced stereoacuity, strabismus and clinically significant refractive errors) and any other ocular problem (eg, nystagmus).

RESULTS

Overall, 26.5% of the screened children had a visual problem, including 5.9% with amblyopia. Using all five tools, screening sensitivity=84% (95% CI 78 to 89), specificity=49% (95% CI 44 to 53), PPV=37% (95% CI 33 to 42), and NPV=90% (95% CI 86 to 93). The odds of having a correct screening result in SK (mean age=68.2 months) was 1.5 times those in JK (mean age=55.6 months; 95% CI 1.1 to 2.1), with sensitivity improved to 89% (95% CI 80 to 96) and specificity improved to 57% (95% CI 50 to 64) among SK children.

CONCLUSIONS

A school-based screening programme correctly identified 84% of those kindergarten children who were found to have a visual problem by a cyclopleged optometry exam. Additional analyses revealed how accuracy varies with different combinations of screening tools and referral criteria.

Simultaneous Changes in Astigmatism with Noncycloplegia Refraction and Ocular Biometry in Chinese Primary Schoolchildren

Purpose

To assess the changing profile of astigmatism in Chinese schoolchildren and the association between astigmatism changes and ocular biometry.

Methods

We examined and followed up 1,463 children aged 6–9 years from Wenzhou, China. We measured noncycloplegic refraction twice each year and tested axial length (AL) and corneal radius of curvature (CRC) annually for two years. We defined clinically significant astigmatism (CSA) as ≤−0.75 diopter (D) and non-CSA astigmatism as ≤0 to >−0.75 D.

Results

Prevalence of CSA at baseline was 22.4% (n = 327) and decreased to 20.3% (n = 297) at the two-year follow-up (P = 0.046). Ninety-two (8.1%) non-CSA children developed CSA. In multiple regression, after adjusting for age, gender, baseline cylinder refraction, and axis, children who had longer baseline ALs (>23.58 mm; odds ratio (OR) = 5.19, 95% confidence interval (CI): 2.72–9.90) and longer baseline AL/CRC ratio (>2.99, OR = 4.99, 95% CI: 2.37–10.51) were more likely to develop CSA after two years. Four-hundred and two (27.5%) children had increased astigmatism, 783 (53.5%) had decreased, and 278 (19.0%) had no change during the two-year follow-up. Children with increased astigmatism had longer baseline ALs (23.33 mm, P < 0.001), higher AL/CRC ratios (2.99 mm, P < 0.001), and more negative spherical equivalent refraction (SER) (−0.63 D, P < 0.001) compared with the decreased and no astigmatism change subgroups. Also, children in the increased astigmatism subgroup had more AL growth (0.68 mm, P < 0.001), higher increases in AL/CRC ratio (0.08, P < 0.001), and more negative SER change (−0.86 D, P < 0.001) compared with the decreased and no astigmatism change subgroups.

Conclusions

The prevalence of astigmatism decreased slightly over the two-year study period. Longer ALs and higher AL/CRC ratios were independent risk factors for developing CSA. Increased astigmatism was associated with AL growth, AL/CRC ratio increases, and the development of myopia. This trial is registered with ChiCTR1800019915.

Preschool Children Exhibit Evident Compensatory Role of Internal Astigmatism in Distribution of Astigmatism: The Nanjing Eye Study

Purpose

To determine the prevalence and associated risk factors for total, corneal, and residual astigmatism and to evaluate the relations between components of astigmatism in Chinese preschool children.

Methods

In the population-based, cross-sectional Nanjing Eye Study, children were measured for noncycloplegic refractive error using an autorefractor and for biometric parameters using an optical low-coherent reflectometry. Data from right eyes were analyzed to calculate the prevalence of astigmatism using various cutpoints (0.5, 1.0, and 1.5 diopters [D]) and for determining risk factors using logistic regression models. Relations between astigmatism components were assessed using Spearman correlation coefficients (ρ).

Results

Of 1817 children (mean ± SD of age: 54.8 ± 3.5 months, 54.2% male), the median (1st and 3rd quartile) of total, corneal, and residual astigmatism (vectorial difference between total and corneal astigmatism) was -0.25 (-0.50, 0), -1.06 (-1.49, -0.72), and -0.92 (-1.23, -0.62) D and their prevalence rate 1.0 D or more was 14.2%, 56.1%, and 44.2%, respectively. With-the-rule was the most common type in total astigmatism (75.2%) and in corneal astigmatism (88.2%) while against-the-rule was predominant in residual astigmatism (75.6%). A negative correlation was found between corneal J0 and internal J0 (ρ = -0.74, P < 0.001) and between corneal J45 and internal J45 (ρ = -0.87, P < 0.001). Based on compensation factor (CF), defined as the minus ratio of internal astigmatism (vectorial difference between total and anterior corneal astigmatism) and anterior corneal astigmatism, internal J0 compensated for total J0 in varying degrees (CF: 0.1-2) in 91.5% cases, while that percentage for J45 component was 77.2%. In univariate logistic regression model, older age was significantly associated with total astigmatism (odds ratio [OR] = 0.96 for per-month increase, P = 0.03), and larger axial length-corneal radius ratio was significantly associated with higher risk of residual astigmatism (OR = 2.28 for per unit increase, P = 0.03).

Conclusions

The compensatory role of internal astigmatism on reducing corneal astigmatism was prominent in preschool children. Larger axial length-corneal radius ratio was significantly associated with higher risk of residual astigmatism.

Effect of twin pregnancy chorionic properties on maternal and fetal outcomes

OBJECTIVE

This study aimed to determine the effect of twin pregnancy chorionic properties on pregnancy complications and fetal outcomes.

MATERIALS AND METHODS

A total of 559 subjects with gemellary pregnancy were included in the retrospective analysis, and clinical data, such as monitoring data during pregnancy and maternal and fetal outcomes, were recorded in detail. Based on the ultrasound results and methods of the postpartum pathologic examination of the placental membranes, the subjects were divided into the twin group with monochorionic diamnion (MCDA group, n = 198) and twin group with dichorionic diamnion (DCDA group, n = 361). The relationships of different chorionic properties and maternal and fetal outcomes were determined by comparing the maternal complications and fetal outcomes.

RESULTS

The occurrence rate of gemellary pregnancy was 2.97% and that of monochorionic twin pregnancy was 34.8%. The MCDA group showed a higher incidence of pregnancy-induced hypertension, gestational diabetes mellitus, polyhydramnios, premature rupture of membranes, and abruptio placenta and a lower incidence of severe postpartum hemorrhage than the DCDA group. However, the incidence of preterm birth was significantly different (57.6% vs. 45.7%, P < 0.05). Significant differences were also detected in the incidence of fetal loss, complicated twins, neonatal asphyxia, and perinatal death between the two groups (P < 0.05).

CONCLUSION

The incidence of maternal complication (such as pregnancy-induced hypertension, gestational diabetes mellitus, polyhydramnios, premature rupture of membranes, and abruptio placenta and severe postpartum hemorrhage) in the two groups was not significantly different; however, the fetal outcomes in the MCDA group were inferior to those in the DCDA group. The fetal outcomes may be improved by determining the chorionic properties in early pregnancy by using ultrasound and consequently planning for pregnancy monitoring and intervention.

Influence of severity and types of astigmatism on visual acuity in school-aged children in southern China

AIM

To investigate the influence of astigmatism on visual acuity in school-aged children, and to define a cutoff for clinically significant astigmatism.

METHODS

This is a population-based, cross-sectional study. Among 5053 enumerated children aged 5-15y in Guangzhou, 3729 (73.8%) children aged 7-15 with successful cycloplegic auto-refraction (1% cyclopentolate) and a reliable visual acuity measurement were included. Ocular measurement included external eye, anterior segment, media and fundus and cycloplegic auto-refraction. Primary outcome measures included the relationship between severity and subtypes of astigmatism and the prevalence of visual impairment. Three criteria for visual impairment were adopted: best-corrected visual acuity (BCVA) ≤0.7, uncorrected visual acuity (UCVA) ≤0.5 or <0.7 in the right eye.

RESULTS

Increases of cylinder power was significantly associated with worse visual acuity (UCVA: β=0.051, P<0.01; BCVA: β=0.025, P<0.001). A substantial increase in UCVI and BCVI was seen with astigmatism of 1.00 diopter (D) or more. Astigmatism ≥1.00 D had a greater BCVI prevalence than cylinder power less than 1.00 D (OR=4.20, 95%CI: 3.08-5.74), and this was also true for hyperopic, emmetropic and myopic refraction categories. Oblique astigmatism was associated with a higher risk of BCVI relative to with the rule astigmatism in myopic refractive category (OR=12.87, 95%CI: 2.20-75.38).

CONCLUSION

Both magnitude and subtypes of astigmatism influence the prevalence of visual impairment in school children. Cylinder ≥1.00 D may be useful as a cutoff for clinically significant astigmatism.

Refractive Errors and Amblyopia in the UCLA Preschool Vision Program; First Year Results

PURPOSE

To report the outcomes of full ophthalmic examination for preschool children in LA County who failed screening with the Retinomax Autorefractor.

DESIGN

Retrospective, cross-sectional study.

METHODS

Between August 2012 and May 2013, the University of California Los Angeles (UCLA) preschool vision program screened 11 260 preschool children aged 3-5 years in Los Angeles County using the Retinomax Autorefractor only. Of those, 1007 children who failed the screening were examined by an ophthalmologist on the UCLA Mobile Eye Clinic. Data from the eye examination were recorded for all children. Amblyopia was defined as unilateral if there was ≥2 line interocular difference in the best-corrected visual acuity (BCVA) and as bilateral if BCVA was <20/50 for children <4 years old and <20/40 for children ≥4 years old.

RESULTS

Glasses were prescribed for 740 (74%) of those examined. Uncorrected visual acuity for all examined children was 0.4 ± 0.2 (logMAR mean ± SD), and BCVA was 0.2 ± 0.1. Of the 88% who underwent cycloplegia, 58% had hyperopia (spherical equivalent [SE] ≥+0.50 diopter [D]), mean of +2.50 D, and 21% had myopia (SE ≤-0.50 D), mean of -1.40 D. A total of 69% had astigmatism ≥1.50 D, mean of 1.97 D (range 0-5.75). Spherical and cylindrical anisometropia ≥1.00 D were each found in 26% of those examined. Refractive amblyopia was found in 9% of those examined, or 0.8% of the original population. Of the amblyopic subjects, 77% were unilateral.

CONCLUSIONS

Screening of preschoolers with the Retinomax led to diagnosis and early treatment of uncorrected refractive errors and amblyopia. By treating children early, amblyopia may be prevented, quality of life improved, and academic achievements enhanced.

Zagreb Amblyopia Preschool Screening Study: near and distance visual acuity testing increase the diagnostic accuracy of screening for amblyopia

AIM

To present and evaluate a new screening protocol for amblyopia in preschool children.

METHODS

Zagreb Amblyopia Preschool Screening (ZAPS) study protocol performed screening for amblyopia by near and distance visual acuity (VA) testing of 15 648 children aged 48-54 months attending kindergartens in the City of Zagreb County between September 2011 and June 2014 using Lea Symbols in lines test. If VA in either eye was >0.1 logMAR, the child was re-tested, if failed at re-test, the child was referred to comprehensive eye examination at the Eye Clinic.

RESULTS

78.04% of children passed the screening test. Estimated prevalence of amblyopia was 8.08%. Testability, sensitivity, and specificity of the ZAPS study protocol were 99.19%, 100.00%, and 96.68% respectively.

CONCLUSION

The ZAPS study used the most discriminative VA test with optotypes in line as they do not underestimate amblyopia. The estimated prevalence of amblyopia was considerably higher than reported elsewhere. To the best of our knowledge, the ZAPS study protocol reached the highest sensitivity and specificity when evaluating diagnostic accuracy of VA tests for screening. The pass level defined at ≤0.1 logMAR for 4-year-old children, using Lea Symbols in lines missed no amblyopia cases, advocating that both near and distance VA testing should be performed when screening for amblyopia.

Paediatric Refractive Errors in an Eye Clinic in Osogbo, Nigeria

BACKGROUND

Paediatric ophthalmology is an emerging subspecialty in Nigeria and as such there is paucity of data on refractive errors in the country. This study set out to determine the pattern of refractive errors in children attending an eye clinic in South West Nigeria.

METHODS

A descriptive study of 180 consecutive subjects seen over a 2-year period. Presenting complaints, presenting visual acuity (PVA), age and sex were recorded. Clinical examination of the anterior and posterior segments of the eyes, extraocular muscle assessment and refraction were done. The types of refractive errors and their grades were determined. Corrected VA was obtained. Data was analysed using descriptive statistics in proportions, chi square with p value <0.05.

RESULTS

The age range of subjects was between 3 and 16 years with mean age = 11.7 and SD = 0.51; with males making up 33.9%.The commonest presenting complaint was blurring of distant vision (40%), presenting visual acuity 6/9 (33.9%), normal vision constituted >75.0%, visual impairment20% and low vision 23.3%. Low grade spherical and cylindrical errors occurred most frequently (35.6% and 59.9% respectively). Regular astigmatism was significantly more common, P <0.001. The commonest diagnosis was simple myopic astigmatism (41.1%). Four cases of strabismus were seen.

CONCLUSION

Simple spherical and cylindrical errors were the commonest types of refractive errors seen. Visual impairment and low vision occurred and could be a cause of absenteeism from school. Low-cost spectacle production or dispensing unit and health education are advocated for the prevention of visual impairment in a hospital set-up.