Prevalence and time trends of refractive error in Chinese children: A systematic review and meta-analysis

Unveiling the psychological dimensions of myopia progression: Anxiety and perceived parental rearing styles in children and adolescents

PURPOSE

This study aimed to investigate the associations among axial length elongation, anxiety, and perceived parental rearing styles across different refractive error groups in children and adolescents.

METHODS

This hospital-based retrospective study included 193 children and adolescents aged 8-16 years, with one year of follow-up. Ocular examinations included axial length measurements and noncycloplegic subjective refraction. The Screen for Child Anxiety Related Emotional Disorders and the modified version of the Egna Minnen Beträffande Uppfostran for Children were used to evaluate anxiety and perceived parental rearing styles, respectively.

RESULTS

Participants with mild to moderate myopia exhibited a higher proportion of anxiety status than those with emmetropia or hyperopia. Among myopic participants, correlation analysis indicated that anxiety scores were positively associated with axial length elongation, parental rejection, and parental overprotection, while negatively correlated with parental emotional warmth. Multivariate regression analysis revealed that greater axial length elongation and parental rejection increased the risk of higher anxiety scores after adjustment. Mediation analysis showed that parental rejection partially mediated the effect of axial length elongation on anxiety scores, accounting for 29% of the total effect. The association between axial length elongation and anxiety was not identified among participants with emmetropia or hyperopia.

CONCLUSIONS

Among children and adolescents with mild to moderate myopia, greater axial length elongation was significantly associated with higher anxiety scores, with parental rejection mediating 29% of this relationship. These findings underscore the importance of addressing the psychological health and parenting styles of myopic children and adolescents with rapid progression, though prospective studies are needed to confirm these results.

Prevalence and Severity of Astigmatism in Children After COVID-19

Importance

Astigmatism can cause blurred vision at near and distance. It is common among schoolchildren and associated with ametropia. Although the COVID-19 pandemic generated a surge in myopia prevalence in children, the association with child astigmatism remains unknown.

Objective

To report the prevalence of refractive astigmatism and corneal astigmatism in schoolchildren from 2015 to 2023 and explore the associations between the pandemic and astigmatism.

Design, Setting, and Participants

This population-based cross-sectional study stratified all the primary schools registered with Education Bureau in Hong Kong into 7 clustered regions used by Hospital Authority Services in Hong Kong. Participants were schoolchildren aged 6 to 8 years who underwent comprehensive ocular examinations at 2 academic medical centers in Hong Kong from 2015 to 2023. Astigmatism was measured with optical biometry and auto-refractor after cycloplegia.

Exposure

COVID-19 pandemic.

Main Outcomes and Measures

The annual prevalence rates of refractive astigmatism and corneal astigmatism were the primary outcome measures. Logistic regression was used to evaluate the association of the pandemic with the risks of refractive astigmatism and corneal astigmatism. Linear regression was used to explore the association of the pandemic with the magnitudes of refractive astigmatism and corneal astigmatism.

Results

The cohort consisted of 21 655 children: 11 464 boys (52.9%) and 10 191 girls (47.1%); their mean (SD) age was 7.31 (0.90) years. The prevalence rate of refractive astigmatism of at least 1.0 diopter (D) was 21.4% and corneal astigmatism of at least 1.0 D 59.8% in 2015 and increased to 34.7% (difference, 13.3%; 95% CI, 9.3%-17.3%) and 64.7% (difference, 4.9%; 95% CI, 0.5%-9.2%), respectively, in 2022-2023. The pandemic was associated with a 20% increase in the risk of refractive astigmatism (odd ratio [OR], 1.20; 95% CI, 1.09-1.33; P < .001), 26% increase in the risk of corneal astigmatism (OR, 1.26; 95% CI, 1.15-1.38; P < .001), 0.04 D in the magnitude of refractive astigmatism (95% CI, 0.02-0.07; P < .001), and 0.05 D in the magnitude of corneal astigmatism (95% CI, 0.02-0.08; P < .001), compared with the prepandemic period of 2015-2019 and after adjusting for sociodemographic factors, parental astigmatism, and child myopia.

Conclusions and Relevance

This study found an increase in both the prevalence and severity of refractive astigmatism and corneal astigmatism after the COVID-19 pandemic. Corneal changes especially along the steepest meridian may explain some of the progression of corneal astigmatism. The potential impact of higher degrees of astigmatism may warrant dedicated efforts to elucidate the relationship between environmental and/or lifestyle factors, as well as the pathophysiology of astigmatism.

Global burden of blindness and vision loss among children and adolescents: A systematic analysis for the global burden of disease study 2021

AIM

This study investigates the global burden of vision impairment caused by refraction disorders, near vision loss, and other vision loss among children and adolescents from 1990 to 2021. The analysis is categorized globally by sex, age, and socio-demographic index (SDI), with a focus on predicting trends to 2035.

METHODS

Data weas obtained from the Global Burden of Disease Study 2021. We reported the prevalence and disability-adjusted life-years (DALYs) of vision impairment due to refraction disorders, near vision loss, and other vision loss globally. Then, we described the prevalence and DALYs numbers and rates by sex, SDI and age. Next, we analyzed the relationship between rate and SDI. Finally, bayesian age-period-cohort (BAPC) analysis model was used to predict the trends from 2022 to 2035 globally by sex and age.

RESULTS

The prevalence and DALYs rates for refraction disorders had a statistically significant trend of reduction in four age groups globally and were positively associated with SDI. The prevalence and DALYs rates for near vision loss were increasing in four age groups, and were negatively associated with SDI. The BAPC model indicates that the age-specific prevalence and DALYs rates of refraction disorders and other vision loss in both men and women will remain on a downward trend until 2035, while near vision loss continues to rise.

CONCLUSIONS

The findings underscore that there are extensive variations based on the type of vision impairment, age group, sex and SDI. Policies should be tailored to specific types in order to effectively alleviate the burden.

Prevalence and temporal trends in myopia and high myopia children in China: a systematic review and meta-analysis with projections from 2020 to 2050

Background

Myopia rates have risen in the past decades in China. New strategies for the prevention and control of myopia are now available, and understanding the prevalence and future trends in myopia and high myopia in children and adolescents in China may provide insights into the impact of implementing these measures. The study aims to provide updated data on the prevalence of myopia and high myopia in children and to project temporal trends in prevalence from 2020 to 2050 in China.

Methods

A systematic review and meta-analysis searching several databases in both English and Chinese: PubMed, Web of Science, Science Direct, China National Knowledge Infrastructure (CNKI), Wanfang, China Science and Technology Journal Database (CSTJ) with date limits from 01/01/2010 to 11/23/2024 was conducted. We included population-based or school-based studies in China that determined the myopia prevalence, based on the cycloplegic refraction, in children under 20. Studies with a response rate <70% or sample size <200 were excluded. A fixed-effect meta-analysis was used, and projections were made based on three scenarios: experience-based, maximum growth (maximum near-work, minimal outdoor time), and minimum growth (2 h outdoor time daily).

Findings

From 6555 reports, 82 studies with 218,794 participants were included. The overall myopia prevalence was 36.6% (95% CI: 36.4%, 36.8%), with rates of 2.6% in ages 0-4, 22.0% in ages 5-9, 45.4% in ages 10-14, and 67.2% in ages 15-19. High myopia prevalence was 5.3% overall, with rates of 0.1% in ages 0-4, 1.1% in ages 5-9, 3.0% in ages 10-14, and 9.5% in ages 15-19. Projections for 2030 under minimum growth, experience-based, and maximum growth scenarios were 26.8%, 46.2%, 56.0%; 2040 were 19.6%, 54.4%, 65.6%; and 2050 were 14.4%, 61.3%, 71.9%, respectively.

Interpretation

China is facing a substantial and potentially worsening epidemic of childhood myopia. This information will provide data for guiding implementation and evaluating the effectiveness of existing and new nationwide myopia prevention and control programs.

Funding

The Science and Technology Innovation Program of Hunan Province, China (2023RC1079, 2024RC5002).

Prevalence of astigmatism among 99,515 children in different areas of Xi'an City, China

PURPOSE

To investigate the prevalence of astigmatism among children in different areas of Xi'an.

METHODS

A cross-sectional study was conducted in Xi'an, China, involving children from 139 primary schools, 28 junior high schools, and 10 senior high schools. Data on uncorrected visual acuity (UCVA) and non-cycloplegic spherical equivalent (SE) were collected from March 2023 to June 2023 based on a new screening model by the Department of Ophthalmology of Xi'an Central Hospital. Data from the right eye were included in the statistical analysis. Trend changes in astigmatism prevalence across different areas, educational stages, ages, and genders were analyzed using the X² test and trend test.

RESULTS

A total of 99,515 children were included in the analysis. The overall prevalence of astigmatism was 59.3% [95% CI: 59.0% to 59.6%]. The prevalence of astigmatism was higher in urban areas compared to the urban-rural fringe (61.1% [95% CI: 60.6% to 61.6%] vs. 58.3% [95% CI: 57.9% to 58.7%]) (X²trend = 73.174, P < 0.05). Boys had a higher prevalence of astigmatism than girls (59.8% [95% CI: 59.4% to 60.2%] vs. 58.8% [95% CI: 58.6% to 59.0%]) (X²trend = 11.613, P < 0.05). Compared to the primary and senior school, the overall prevalence of astigmatism is most significant during the junior school stage (X²trend = 1710.133, P < 0.05), with rates of 54.6% in primary school, 71.3% in junior high school, and 68.7% in senior high school (X²trend = 10.694-868.913, P < 0.05), among which grade 9 has the highest prevalence (X²trend = 2766.194, P < 0.05). Myopia severity increased with the degree of astigmatism (X²trend = 2547.677, P < 0.05), and boys were more likely to experience worsening myopia with increasing astigmatism compared to girls (X²trend = 36.878, P < 0.05).

CONCLUSIONS

Astigmatism was most prevalent among children in Xi'an during junior school, peaking in grade 9. Urban areas showed higher incidence rates than urban-rural ones, and boys had a consistently higher prevalence than girls, with WTR being the most common type.

The Trends in Prevalence of Blindness Caused by Refraction Disorders in China from 1990 to 2019 and Its Predictions: Findings from the Global Burden of Disease Study 2019

PURPOSE

To examine the burden of blindness caused by refraction disorders (BCRD) in China over the past 30 years by year, age, and sex, and to estimate future projections.

METHODS

Data from the Global Burden of Diseases (GBD) 2019 database were used to analyze the number of cases and age-standardized prevalence rates (ASPRs) of BCRD in China from 1990 to 2019. We focused on changes over time using estimated annual percentage changes (EAPCs). In addition, we performed the Nordpred analysis and the Bayesian Age-Period-Cohort (BAPC) model with integrated nested Laplace approximations to predict the BCRD burden from 2020 to 2034.

RESULTS

The number of prevalent cases due to BCRD increased from 750,956.7 (95% uncertainty interval [UI] 636,381.24-872,040.62) in 1990 to 1,145,881.76 (95% UI 931,966.43-1,342,338.18) in 2019. The ASPRs of BCRD showed a decreasing trend, with EAPCs of -0.58 (95% confidence interval [CI] -0.81-0.36). The older and female populations had a higher BCRD burden. The number of prevalent cases due to BCRD is projected to continue to increase from 1.33 million in 2020 to 1.86 million in 2034. The ASPR also showed an increasing trend over the next 15 years.

CONCLUSION

Over the past three decades, the prevalence of BCRD in China has improved in both sexes and will continue to increase in the next 15 years. This study highlights the importance of prevention of BCRD, especially for women and the elderly.

Refractive errors in Tianjin youth aged 6-18 years: exploring urban-rural variations and contributing factors

Purpose

Refractive errors, particularly myopia, constitute a significant global public health concern, contributing to morbidity and disability. A more comprehensive understanding of the determinants of refractive errors and the differences between urban and rural areas is essential to develop effective preventive measures for youth. This study aimed to compare the prevalence and risk factors of refractive errors among youth in urban and rural Tianjin, China.

Methods

This school-based cross-sectional study was conducted in 2022. Elementary, middle, and high school students aged 6-18 years from both urban and rural areas of Tianjin were included. All participants underwent visual acuity testing and refractive measurement and completed comprehensive questionnaires.

Results

A total of 346,146 participants (176,628 boys) were included in this investigation (50.36% for urban and 49.64% for rural, respectively). Myopia, hyperopia, astigmatism, and anisometropia were present in 56.8, 9.7, 56.64, and 21.3% of urban students, respectively. Similarly, rural students had a prevalence of 57.6, 11.5, 56.48, and 22.0% for the respective conditions. Compared to rural students, after adjusting for age, sex, and other significant variables, urban students were 1.05 times more likely to have myopia (95% CI: 1.03-1.07, p < 0.0001), 0.71 times less likely to have hyperopia (95% CI: 0.69-0.73, p < 0.0001), and 1.02 times more likely to have astigmatism (95% CI: 0.69-0.73, p < 0.0001). There was no significant association between anisometropia and residence (OR: 1.00, 95% CI: 0.98-1.02, p = 0.9850). Sociodemographic and physiological factors contribute to the disparities in the prevalence of refractive errors between urban and rural areas. Age, increased near-work activities, and Decreased outdoor time were identified as risk factors for myopia, astigmatism, and anisometropia. Conversely, the absence of a parental history of refractive errors emerged as a protective factor for myopia and astigmatism among students. Lower parental education levels were negatively correlated with the risk of myopia and anisometropia in their children. Specifically, the lower the parental education, the greater the risk of myopia in their offspring. For urban students only, lower parental education was associated with an increased risk of astigmatism.

Conclusion

Crude prevalence estimates May not accurately reflect the true burden of refractive error due to confounding factors such as age and sex. Accounting for these factors revealed that urban students were more likely to have myopia and astigmatism but less likely to have hyperopia compared to their rural counterparts. These disparities highlight the importance of considering geographical variations when implementing strategies for myopia control and prevention.

The Systemic Genotype-Phenotype Characterization of PAX6-Related Eye Disease in 164 Chinese Families

Purpose

This study aims to evaluate the genetic and phenotypic characteristics and elucidate the genotype-phenotype correlations of a large Chinese cohort with PAX6-related disorders.

Methods

Variants detected with exome sequencing were filtered through multistep bioinformatic and co-segregation analyses, and validated by Sanger sequencing. The related clinical data were collected, and cluster analysis and statistical analysis of the PAX6-related phenotypes across different variant groups were carried out. Parental mosaicism was investigated using cloning analysis and Droplet digital PCR.

Results

A total of 119 pathogenic or likely pathogenic PAX6 variants, including 74 truncation, 31 missense, and 14 others, were identified in 228 patients from 164 unrelated families. The most common phenotypes were foveal hypoplasia (97.8%), nystagmus (92.6%), aniridia (76.7%), cataract (36.8%), and iris hypoplasia (22.4%). Mosaicism ranging from 13.9% to 18.8% was identified in 3 unrelated patients' parents with relatively mild phenotypes. Missense variants in the linker region of the paired domain were associated with high myopia, whereas truncation variants in the homeodomain and proline-serine-threonine-rich domain were associated with hyperopia. Similarly, the degree of iris defects, visual acuity, and associated ocular comorbidity varied among the different types and locations of PAX6 variants.

Conclusions

Our data indicate that foveal hypoplasia but not aniridia is the most common sign of PAX6-related disorders, contributing to subtle iris changes that might easily be overlooked in clinical practice. Recognition of mosaicism in atypical cases or parents with very mild phenotypes is important in genetic counseling as their offspring are at increased risk of typical aniridia. Recognition of the genotype-phenotype relationship emphasizes involvement of PAX6 regulation in shaping complex ocular phenotypes.

Characteristics of astigmatism in school-age children aged 5 to 13 years in northeast Sichuan: a cross-sectional school-based study

Background

Astigmatism is closely associated with myopia progression, vision loss, eye fatigue and amblyopia, which seriously endangers children's eye health. This study aims to investigate the prevalence and characteristic distribution of astigmatism in children in Langzhong City, providing valuable insights for allocating resources and develop prevention and control strategies.

Methods

A cross-sectional study and random sampling survey were conducted. Between January and November 2021, 21,415 students aged 5 to 13 years from 14 primary schools in Langzhong City underwent non-cycloplegic refractive testing using autorefraction. The data on myopia were analyzed using SPSS (Statistical Package for the Social Sciences) version 23.0.

Results

The inclusion criterion was set at an absolute astigmatism value of ≥0.50D. Among the 21,415 children studied, 61.70% were found to have astigmatism. The prevalence of astigmatism varied significantly across different grades (χ2=501.414, P<0.001). The predominant types of astigmatism were mild astigmatism (0.50-1.00D) and with-the-rule astigmatism. Mixed astigmatism was primarily observed in children in grades 1 and 2, while compound myopic astigmatism was more common in children in grades 3 to 6. These differences were statistically significant. As the degree of astigmatism increased, the proportions of against-the-rule astigmatism, oblique astigmatism, compound myopic astigmatism, and simple hyperopic astigmatism decreased, whereas the proportions of with-the-rule astigmatism, mixed astigmatism, and compound hyperopic astigmatism increased.

Conclusions

The prevalence of astigmatism among school-age children aged 5 to 13 years in northeast Sichuan is notably high, with compound myopic astigmatism and with-the-rule astigmatism being the most common types. Regular refractive examinations are crucial for the early detection and management of astigmatism.

Socioeconomic disparities and green space associated with myopia among Chinese school-aged students: A population-based cohort study

Background

There is increasing evidence on the link between environmental factors and myopia in children and adolescents, yet with inconsistent conclusions. We investigated the associations between socioeconomic inequalities and green space with myopia in school-aged students participating in the Tianjin Child and Adolescent Research of Eye (TCARE) study.

Methods

We obtained data from a population-based dynamic cohort study conducted in Tianjin, China, in 2021 and followed up in 2022. We included 1 245 271 participants from 16 districts with an average age of 11.6 years (standard deviation = 3.3) in our analysis. We synthesized their area-level SES through a prediction model that combined economic, educational, and health care variables and assessed the greenness levels surrounding the school using the Normalized Difference Vegetation Index (NDVI) based on data obtained through satellite remote sensing. We performed generalised linear mixed effects analyses for each myopia outcome separately, with adjustments for students' sex, years of education completed, and the school's geographical location.

Results

We observed that students living in low SES areas had the highest prevalence of myopia (60.7%) in the last screening in 2022, as well as a higher incidence of one-year myopia (26.4%) compared to those residing in middle SES areas (22.7%). With a 0.1 increase in the 250, 500, and 1000 m buffer NDVI, the prevalence of myopia dropped by 6.3% (odds ratio (OR) = 0.937; 95% confidence interval (CI) = 0.915, 0.960), 7.7% (OR = 0.923; 95% CI = 0.900, 0.946), and 8.7% (OR = 0.913; 95% CI = 0.889, 0.937), respectively. The interaction analysis showed that low SES and low greenness exacerbate the prevalence of myopia. Findings from longitudinal analyses consistently demonstrated a correlation between higher values of NDVI and a slower progression of myopia. These findings remained robust across sensitivity analyses, including for variables on parental myopia and students' behaviors.

Conclusions

Exposure to green spaces could play a crucial role in slowing the progression of myopia among school-aged students. Myopia control policies should prioritise young populations residing in low SES areas with limited access to green spaces, as they face the highest potential risks.

Impact of ophthalmic clinical service use in mitigating myopia onset and progression in preschool children: a retrospective cohort study

BACKGROUND

Although school screenings identify children with vision problems and issue referrals for medical treatment at an ophthalmic hospital, the effectiveness of this approach remains unverified.

OBJECTIVE

To investigate the impact of ophthalmic clinical services on the onset and progression of myopia in preschool children identified with vision impairment.

METHODS

Using data from the Shanghai Child and Adolescent Large-scale Eye Study (SCALE), this retrospective cohort study evaluated the visual development of children from three districts-Jing'an, Minhang, and Pudong-which are representative of geographic diversity and economic disparity in Shanghai's 17 districts. Initially, in 2015, the study encompassed 14,572 children aged 4-6 years, of whom 5,917 needed a referral. Our cohort consisted of 5,511 children who had two or more vision screenings and complete personal information over the follow-up period from January 2015 to December 2020. We divided these children into two groups based on their initial spherical equivalent (SE): a High-risk group (SE > -0.5 D) and a Myopia group (SE ≤ -0.5 D). Within each of these groups, we further categorized children into Never, Tardily, and Timely groups based on their referral compliance to compare the differences in the occurrence and progression of myopia. Cox proportional models were applied to estimate hazard ratios (HRs) for myopia incidence per person-years of follow-up in High-risk group. Generalized additive models(GAM) was used to calculating the progression for annual spherical equivalent changes in all children.

RESULTS

Of the 5,511 preschool children (mean age, 5.25 years; 52.24% male) who received a referral recommendation, 1,327 (24.08%) sought clinical services at an ophthalmic hospital. After six years of follow-up, 65.53% of children developed myopia. The six-year cumulative incidence of myopia in the Never, Tardily, and Timely groups was 64.76%, 69.31%, and 57.14%, respectively. These percentages corresponded to hazard ratios (HRs) of 1.31 (95% CI, 1.10-1.55) for the Tardily group and 0.55 (95% CI, 0.33-0.93) for the Timely group, compared with the Never group. The HRs were adjusted for age, sex, and SE at study entry. Interestingly, the Timely group showed significantly less SE progression than the other groups (P < 0.001), and SE progression was higher in the High-risk group (-0.33 ± 0.37D/year) than in children with myopia (-0.08 ± 0.55D/year).

CONCLUSION

Timely utilization of ophthalmic clinical services among children aged 4 to 6 years who fail school vision screenings can significantly reduce the incidence of myopia and slow SE progression.

Prevalence of visual impairment and estimation of refractive errors among school children in Kakamega, Kenya

AIM

To investigate the prevalence of visual impairment (VI) and provide an estimation of uncorrected refractive errors in school-aged children, conducted by optometry students as a community service.

METHODS

The study was cross-sectional. Totally 3343 participants were included in the study. The initial examination involved assessing the uncorrected distance visual acuity (UDVA) and visual acuity (VA) while using a +2.00 D lens. The inclusion criteria for a subsequent comprehensive cycloplegic eye examination, performed by an optometrist, were as follows: a UDVA<0.6 decimal (0.20 logMAR) and/or a VA with +2.00 D ≥0.8 decimal (0.96 logMAR).

RESULTS

The sample had a mean age of 10.92±2.13y (range 4 to 17y), and 51.3% of the children were female (n=1715). The majority of the children (89.7%) fell within the age range of 8 to 14y. Among the ethnic groups, the highest representation was from the Luhya group (60.6%) followed by Luo (20.4%). Mean logMAR UDVA choosing the best eye for each student was 0.29±0.17 (range 1.70 to 0.22). Out of the total, 246 participants (7.4%) had a full eye examination. The estimated prevalence of myopia (defined as spherical equivalent ≤-0.5 D) was found to be 1.45% of the total sample. While around 0.18% of the total sample had hyperopia value exceeding +1.75 D. Refractive astigmatism (cil<-0.75 D) was found in 0.21% (7/3343) of the children. The VI prevalence was 1.26% of the total sample. Among our cases of VI, 76.2% could be attributed to uncorrected refractive error. Amblyopia was detected in 0.66% (22/3343) of the screened children. There was no statistically significant correlation observed between age or gender and refractive values.

CONCLUSION

The primary cause of VI is determined to be uncorrected refractive errors, with myopia being the most prevalent refractive error observed. These findings underscore the significance of early identification and correction of refractive errors in school-aged children as a means to alleviate the impact of VI.

The Impact of Sunshine Duration on Myopia in Central China: Insights from Populational and Spatial Analysis in Hubei

Purpose

This study aimed to analyze myopia distribution in Hubei and the impact of regional Sunshine Duration on myopia in children and adolescents.

Patients and Methods

The Cross-sectional study included students (kindergarten to grade 12) through multistage cluster stratified sampling in 17 cities (103 areas) of Hubei, China, who underwent ophthalmic examinations from September 2021 to November 2021. The association of sunshine duration with the prevalence and distribution of myopia was analyzed. Using Moran's index to quantify the distribution relationship, a spatial analysis was constructed.

Results

A total of 435,996 students (53.33% male; mean age, 12.16±3.74 years) were included in the study. A negative association was identified between myopia prevalence and sunshine duration in the region, especially in population of primary students (r=-0.316, p<0.001). Each 1-unit increment in the sunshine duration was associated with a decreased risk of myopia prevalence (OR=0.996; 95% CI, 0.995-0.998; P <0.001). Regression showed a linear relationship between sunshine duration and myopia rates of primary school students [Prevalence%= (-0.1331*sunshine duration+47.73)%, p = 0.02]. Sunshine duration influenced the distribution of myopia rates among primary (Moran's I=-0.206, p<0.001) and junior high school (Moran's I=-0.183, p=0.002). Local spatial analysis showed that areas with low sunshine duration had high myopia prevalence concentration.

Conclusion

This study revealed sunshine duration associations with myopia prevalence at the regional and population levels. The results may emphasize the significance of promptly implementing myopia control in regions with poor sunshine. The effect of sunshine on myopia is pronounced in the early years of education, especially in primary students.

Application of sentiment and word frequency analysis of physician review sites to evaluate refractive surgery care

Background

Online physician reviews increase transparency in health care, helping patients make informed decisions about their provider. Language processing techniques can quantify this data and allow providers to better understand patients' experiences, perspectives, and priorities. The objective of this study was to assess patient satisfaction and understand the aspects of care that are valued by patients seeking refractive care using sentiment and word frequency analysis.

Methods

Written reviews and Star ratings for members of the Refractive Surgery Alliance Society practicing in the United States were collected from Healthgrades, a popular physician rating website. Surgeons with at least one written review were included in the study. Reviews were scored from -1 (most negative) to +1 (most positive) using Valence Aware Dictionary sEntiment Reasoner (VADER). Reviews were stratified by demographic characteristics, namely gender, region, and years in practice. Word frequency analysis was applied to find the most common words and phrases.

Results

A total of 254 specialists and 3104 reviews were analyzed, with an average of 4.4/5 stars and mean 48 ratings each. Most physicians had positive reviews (96%, average VADER ​= ​0.69). Younger physicians (<20 years since residency) had significantly higher Stars rating than senior peers (>20 years) (P ​< ​0.001). A similar trend was observed in VADER score (0.71 vs 0.69), although not statistically significant (P ​= ​0.06). No statistical differences were observed between Stars rating and VADER score by gender (P ​= ​0.66, P ​= ​0.83) or by geographical region (P ​= ​0.74, P ​= ​0.07). "Staff" (n ​= ​1269), "professional" (n ​= ​631), "office" (n ​= ​523), "questions" (n ​= ​424), and "friendly" (n ​= ​386) were frequently used in reviews, along with phrases such as "the staff" (n ​= ​273) and "my questions" (n ​= ​174). "Surgery" (n ​= ​719), "staff" (n ​= ​576), "procedure" (n ​= ​251), "experience" (n ​= ​243), and "professional" (n ​= ​240) were the most common words in positive reviews, while "surgery" (n ​= ​147), "office" (n ​= ​86), "staff" (n ​= ​54), "time" (n ​= ​47), and "insurance" (n ​= ​28) were the most commonly used in negative reviews.

Conclusions

Both the average Stars and VADER sentiment score suggest a high satisfaction among refractive patients. Word frequency analysis revealed that patients value non-clinical aspects of care, including interactions with staff, insurance coverage, and wait-times, suggesting that improving non-clinical factors could enhance patient satisfaction with refractive surgery.

Prediction of Visual Outcome After Rhegmatogenous Retinal Detachment Surgery Using Artificial Intelligence Techniques

Purpose

This study aimed to develop artificial intelligence models for predicting postoperative functional outcomes in patients with rhegmatogenous retinal detachment (RRD).

Methods

A retrospective review and data extraction were conducted on 184 patients diagnosed with RRD who underwent pars plana vitrectomy (PPV) and gas tamponade. The primary outcome was the best-corrected visual acuity (BCVA) at three months after the surgery. Those with a BCVA of less than 6/18 Snellen acuity were classified into a vision impairment group. A deep learning model was developed using presurgical predictors, including ultra-widefield fundus images, structural optical coherence tomography (OCT) images of the macular region, age, gender, and preoperative BCVA. A fusion method was used to capture the interaction between different modalities during model construction.

Results

Among the participants, 74 (40%) still had vision impairment after the treatment. There were significant differences in age, gender, presurgical BCVA, intraocular pressure, macular detachment, and extension of retinal detachment between the vision impairment and vision non-impairment groups. The multimodal fusion model achieved a mean area under the curve (AUC) of 0.91, with a mean accuracy of 0.86, sensitivity of 0.94, and specificity of 0.80. Heatmaps revealed that the macular involvement was the most active area, as observed in both the OCT and ultra-widefield images.

Conclusions

This pilot study demonstrates that artificial intelligence techniques can achieve a high AUC for predicting functional outcomes after RRD surgery, even with a small sample size. Machine learning methods identified The macular region as the most active region.

Translational Relevance

Multimodal fusion models have the potential to assist clinicians in predicting postoperative visual outcomes prior to undergoing PPV.

The Current and Future Landscape of the Childhood Myopia Epidemic in China-A Review

Over the last two decades, the prevalence of myopia has gradually increased in China. Numerous epidemiological studies suggest that education and inadequate time spent outdoors are the major causes of the current myopia epidemic. China is one of the few countries that has begun to address the myopia epidemic with a national-level strategy, implementing nationwide education reform, cost-reduction measurements, and dissemination of information on myopia prevention and control. These "natural experiments" will provide insights into areas that may face similar or potential myopia problems.

Development and validation of predictive models for myopia onset and progression using extensive 15-year refractive data in children and adolescents

BACKGROUND

Global myopia prevalence poses a substantial public health burden with vision-threatening complications, necessitating effective prevention and control strategies. Precise prediction of spherical equivalent (SE), myopia, and high myopia onset is vital for proactive clinical interventions.

METHODS

We reviewed electronic medical records of pediatric and adolescent patients who underwent cycloplegic refraction measurements at the Eye & Ear, Nose, and Throat Hospital of Fudan University between January 2005 and December 2019. Patients aged 3-18 years who met the inclusion criteria were enrolled in this study. To predict the SE and onset of myopia and high myopia in a specific year, two distinct models, random forest (RF) and the gradient boosted tree algorithm (XGBoost), were trained and validated based on variables such as age at baseline, and SE at various intervals. Outputs included SE, the onset of myopia, and high myopia up to 15 years post-initial examination. Age-stratified analyses and feature importance assessments were conducted to augment the clinical significance of the models.

RESULTS

The study enrolled 88,250 individuals with 408,255 refraction records. The XGBoost-based SE prediction model consistently demonstrated robust and better performance than RF over 15 years, maintaining an R2 exceeding 0.729, and a Mean Absolute Error ranging from 0.078 to 1.802 in the test set. Myopia onset prediction exhibited strong area under the curve (AUC) values between 0.845 and 0.953 over 15 years, and high myopia onset prediction showed robust AUC values (0.807-0.997 over 13 years, with the 14th year at 0.765), emphasizing the models' effectiveness across age groups and temporal dimensions on the test set. Additionally, our classification models exhibited excellent calibration, as evidenced by consistently low brier score values, all falling below 0.25. Moreover, our findings underscore the importance of commencing regular examinations at an early age to predict high myopia.

CONCLUSIONS

The XGBoost predictive models exhibited high accuracy in predicting SE, onset of myopia, and high myopia among children and adolescents aged 3-18 years. Our findings emphasize the importance of early and regular examinations at a young age for predicting high myopia, thereby providing valuable insights for clinical practice.

Diagnostic performance of wide-field optical coherence tomography angiography in detecting open-angle glaucoma in high myopia

PURPOSE

To compare the diagnostic performance of the capillary density (CD) of the central 1-6 mm and peripheral 6-12 mm annular regions in detecting open-angle glaucoma in high myopia (HM) using 15 × 12 mm wide-field swept-source optical coherence tomography angiography (WF SS-OCTA).

METHODS

The study enrolled 206 and 103 eyes with HM and highly myopic open-angle glaucoma (HM-OAG), respectively. WF SS-OCTA images centred on the fovea were obtained to analyse the changes in the CD in the 1-3 mm, 3-6 mm, 6-9 mm, and 9-12 mm annular regions. CD of the superficial capillary plexus (SCP) was measured with the built-in software. The area under the receiver operating characteristic curve (AUROC) of each region was compared.

RESULTS

The diagnostic performance of the SCP CD in the central 1-6 mm annular region (AUROC = 0.849) was better than that in the peripheral 6-12 mm annular region (AUROC = 0.756, p = 0.001). The annular AUROCs of SCP CD peaked in the 3-6 mm annular region (AUROC = 0.858) and gradually decreased with increasing diameter and were lower than the corresponding AUROCs of the ganglion cell-inner plexiform layer thickness (p < 0.05 for all comparisons). SCP CD of the inferior quadrant in the 3-6 mm annular region had the best diagnostic performance (AUROC = 0.859).

CONCLUSION

The SCP CD in the central 1-6 mm annular region exhibited better diagnostic performance for the detection of HM-OAG in HM. The assessment of more peripheral regions has no added value in detecting glaucoma in HM.

Comparative Proteomic Analysis of Aqueous Humor Reveals Biochemical Disparities in the Eyes of High Myopic Patients

Myopia accounts for a significant proportion of visual lesions worldwide and has the potential to progress toward pathological myopia. This study aims to reveal the difference in protein content in aqueous humor between high myopic and nonhigh myopic patients, as well as better understand the dysregulation of proteins in myopic eyes. Aqueous humor was collected for liquid chromatograph mass spectrometer (LC/MS) analysis from 30 individual eyes that underwent phacoemulsification and intraocular lens (IOL) implantation. Results showed that a total of 190 differentially expressed proteins were identified, which revealed their involvement in cell metabolism, immune and inflammatory response, and system and anatomical structure. Further analysis focused on 15 intensively interacted hub proteins, encompassing functions related to complement cascades, lipoprotein metabolism, and fibrin biological function. Subsequent validations demonstrated elevated levels of APOE (apolipoprotein E), C3 (complement 3), and AHSG (α-2-HS-glycoprotein) in the high myopia group (31 eyes of cataracts and 45 eyes of high myopia with cataracts). AHSG had a significant positive correlation with axial length in high myopic patients, with good efficacy in distinguishing between myopic and nonmyopic groups. AHSG may be a potential indicator of the pathological severity and participator in the pathological progress of high myopia. This study depicted differential expression characteristics of aqueous humor in patients with high myopia and provided optional information for further experimental research on exploring the molecular mechanisms and potential therapeutic targets for high myopia. Data are available via ProteomeXchange with the identifier PXD047584.

Prevalence of and risk factors for myopia among urban and rural children in Northeast China: protocol for a school-based cross-sectional study

INTRODUCTION

The worldwide prevalence of myopia is high and continues to increase. In this study, a school screening programme for myopia will be implemented using the whole-process information method. The purpose of this study is to investigate the prevalence of myopia in urban and rural areas of Northeast China and to determine the factors related to myopia.

METHODS AND ANALYSIS

This is a school-based cross-sectional study. Our study population will include 6000 school-aged children from 2 urban and 2 rural schools in Jinzhou, China. The study will be conducted using our self-developed internet-based intelligent data collection, transmission, storage and analysis system. Examination parameters include uncorrected distance visual acuity, presenting distance visual acuity, non-cycloplegic autorefraction, height, weight, waist circumference, hip circumference, spinal curvature and dental caries. The examination report will be automatically sent to parents, who will complete the questionnaire, and appropriate statistical analysis will be performed. The main outcome is the prevalence of myopia, defined as an equivalent spherical degree ≤-0.5 D.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Third Affiliated Hospital of Jinzhou Medical University (number: JYDSY-KXYJ-IEC-2023-018). Findings will be published in a peer-reviewed journal. Subjects and their parents (or other authorised agents) give informed consent prior to study participation.

TRIAL REGISTRATION NUMBER

ChiCTR2300072893.

Individual-level socioeconomic status and cataract-induced visual disability among older adults in China: the overview and urban-rural difference

Objective

To investigate the prevalence of cataract-induced visual disability and its association with individual-level socioeconomic status (SES) among older adults in China.

Methods

Using the data of 354,743 older adults (60 years and older) from the Second China National Sample Survey on Disability in 2006. Cross-sectional study design was applied. The differences in visual disability prevalence of cataracts among sociodemographic subgroups were analyzed by the chi-square test, and the association between individual-level SES and cataract-induced visual disability was investigated by the multivariate logistic regression model.

Results

The weighted visual disability prevalence of cataracts was 4.84% in 2006. Older people with a higher household income per capita (OR = 0.83, 95% CI: 0.81-0.85), higher education level (primary school vs. illiteracy: OR = 0.80, 95% CI: 0.76-0.83; ≥undergraduate college vs. illiteracy: OR = 0.31, 95% CI: 0.25-0.39), and occupation (OR = 0.53, 95% CI: 0.50-0.56) were less likely to suffer from cataract-induced visual disability. Household income per capita and education level increase played a greater role in decreasing the risk of visual disability caused by cataracts in urban areas, while having occupation contributed more to reducing the risk of disability in rural areas.

Conclusion

The gap in individual-level SES is closely related to the visual health inequities among older Chinese people and there are two distinct mechanisms in rural and urban areas. Strategies to promote collaborative healthcare development regionally, strengthen safeguards for disadvantaged groups, and increase public awareness of visual disability prevention are warranted.

Prevalence and associated factors of myopia among school students in Shenyang, China: a cross-sectional study

Background

In recent years, the prevalence of myopia has increased significantly and caused great concern. Nevertheless, an estimate of myopia in the student population in Shenyang, Liaoning Province, China is still lacking. This study aims to determine the prevalence of myopia among students in Shenyang and investigate the associated factors affecting myopia development.

Methods

Standard logarithmic visual acuity chart and automatic computerized optometry under non-ciliary muscle paralysis were used to test the students' naked visual acuity of their right and left eyes. The included students were organized to fill in questionnaires on WeChat to collect the factors affecting myopia.

Results

A total of 34,644 students with a median age of 11.9 years were examined, including 17,563 males and 17,081 females. The overall prevalence of myopia was 60%, with a prevalence of 45% for mild myopia, 13% for moderate myopia, and 1.9% for high myopia. The sex, high educational stage, family history of myopia, doing homework after school or reading and writing for more than 2 h were associated with a higher risk of myopia, while doing eye exercises twice a day or more, going outdoors during recess, reading and writing with eyes more than one foot from books, and sleeping more than 8 h a day were associated factors for preventing myopia. The associated factors influencing myopia vary among different subgroups.

Conclusion

The prevalence of myopia in Shenyang is at a high level. In addition to sex, high educational stage and genetic factors, environmental factors including length of eye usage, eye exercises, outdoor activities, eye working distance, and sleep duration are associated with myopia prevalence. Therefore, it is recommended that the occurrence and development of myopia can be prevented by controlling the above environmental factors.

Determinants of Health Care Needs in Relation to Vision Correction among Adolescents in the United Arab Emirates: A Cross-Sectional Study

BACKGROUND

Uncorrected refractive error has been suggested to affect children's development, educational performance, and socialization. Sociodemographic and environmental differences among individuals may impact their accessibility to utilizing appropriate services, impacting their vision-dependent activities.

METHODS

Guided by the population health framework, this retrospective study assessed the prevalence of self-reported vision correction needs and its determinants for a sample of adolescents (n = 6363) from the United Arab Emirates (UAE) aged 13 to 20 years between 2007 to 2009.

RESULTS

The findings suggest a relatively high prevalence of self-reported vision correction needs (26.8%), with among 24.8% males and 31.7% among females. Factors that were significantly associated with vision correction needs included age, biological sex, location of residence (emirate), nationality, parental education and employment level, household financial status, screen time use, visiting an eye specialist in the past year, and daily functional capacity.

CONCLUSION

Reporting the vision correction needs of the adolescent population and identifying its determinants may help identify and resolve modifiable barriers to accessing the appropriate vision care resources. Further research in assessing the type of refractive error, potential genetic and environmental factors, and vision care services in each emirate may help decision-makers set appropriate policies to improve the overall quality of eye health.

IMI 2023 Digest

Myopia is a dynamic and rapidly moving field, with ongoing research providing a better understanding of the etiology leading to novel myopia control strategies. In 2019, the International Myopia Institute (IMI) assembled and published a series of white papers across relevant topics and updated the evidence with a digest in 2021. Here, we summarize findings across key topics from the previous 2 years. Studies in animal models have continued to explore how wavelength and intensity of light influence eye growth and have examined new pharmacologic agents and scleral cross-linking as potential strategies for slowing myopia. In children, the term premyopia is gaining interest with increased attention to early implementation of myopia control. Most studies use the IMI definitions of ≤-0.5 diopters (D) for myopia and ≤-6.0 D for high myopia, although categorization and definitions for structural consequences of high myopia remain an issue. Clinical trials have demonstrated that newer spectacle lens designs incorporating multiple segments, lenslets, or diffusion optics exhibit good efficacy. Clinical considerations and factors influencing efficacy for soft multifocal contact lenses and orthokeratology are discussed. Topical atropine remains the only widely accessible pharmacologic treatment. Rebound observed with higher concentration of atropine is not evident with lower concentrations or optical interventions. Overall, myopia control treatments show little adverse effect on visual function and appear generally safe, with longer wear times and combination therapies maximizing outcomes. An emerging category of light-based therapies for children requires comprehensive safety data to enable risk versus benefit analysis. Given the success of myopia control strategies, the ethics of including a control arm in clinical trials is heavily debated. IMI recommendations for clinical trial protocols are discussed.

Prevalence of refractive errors in Nepalese children and adults: a systematic review with meta-analysis

CLINICAL RELEVANCE

Country-specific estimates of the prevalence of refractive errors are important to formulate national eye health policies for refractive care services.

BACKGROUND

The purpose of this study was to systematically synthesise available literature and estimate the prevalence of refractive errors in the Nepalese population.

METHODS

PubMed, Scopus, and Web of Science databases were systematically searched for articles on refractive errors and presbyopia published in English language until 27 September 2022. Population and school-based quantitative, cross-sectional prevalence studies and Rapid Assessment of Avoidable Blindness survey repository data were included. The quality of the included studies was assessed using the Newcastle Ottawa scale adapted for cross-sectional studies. Data extraction was performed with consensus among the reviewers. Meta-analysis of the prevalence was performed using the Random effects model to estimate the pooled proportions.

RESULTS

A total of 38 studies with 101 701 participants were included: 18 studies in children (n = 31 596) and 20 in adults (n = 70 105). In children, the estimated pooled prevalence of overall refractive errors was 8.4% (95% CI: 4.8 to 12.9) with myopia, hypermetropia and astigmatism prevalent in 7.1% (95% CI: 3.7 to 11.4), 1.0% (95% CI: 0.7 to 1.3) and 2.2% (95% CI: 0.9 to 3.9), respectively. In adults, the prevalence of refractive errors, uncorrected refractive errors, and uncorrected presbyopia were 11.2% (95% CI: 8.0 to 14.9), 7.3% (95% CI: 5.4 to 9.5) and 78.9% (95% CI: 69.1 to 87.3), respectively.

CONCLUSIONS

The pooled prevalence of refractive errors is relatively low while uncorrected refractive errors and presbyopia are high in Nepalese population suggesting a need for better access to refractive care services in the country. The paucity of quality evidence on prevalence of refractive errors, particularly in children, indicates a need for a well-designed population-based study to accurately estimate the current prevalence of refractive errors.

Comparison of the accuracy of three intraocular lens power calculation formulas in cataract patients with prior radial keratotomy

PURPOSE

To compare the accuracy of three intraocular lens (IOL) formulas in Chinese cataract patients with prior radial keratotomy (RK).

METHODS

Medical records of cataract patients with prior RK at Beijing Tongren Hospital were retrospectively analysed. The absolute error (AE) was calculated as the absolute difference between the actual postoperative spherical equivalent and the predicted spherical equivalent. The AE and percentages of eyes with AE within 0.5D, 1.0D, and 2.0D for three formulas [Barrett True-K, Holladay 1 (D-K), Haigis] were calculated and compared.

RESULTS

Forty-seven eyes of 28 cataract patients were included. The Median AE (MedAE) was significantly different among the three formulas (P < 0.001). The MedAE was lowest for the Barrett True-K formula (0.62), followed by the Haigis (0.76), and Holladay 1 (D-K) (1.16). The percentages of eyes with AE within 0.5D, and 1.0D were significantly different among the 3 formulas (P = 0.009, and P < 0.001). The Barrett True-K formula achieved the highest percentages (46.8%) of eyes with AE within 0.5D. Haigis achieved the highest percentages (70.21%) of eyes with AE within 1.0 D.

CONCLUSIONS

Barrett True-K is the most accurate IOL power calculation formula among the 3 formulas and Haigis is an alternative choice. Considering the relatively lower accuracy of IOL formulas in cataract patients with prior RK, newer and more accurate IOL formulas are desirable.

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.

Regional variations and temporal trends of childhood myopia prevalence in Africa: A systematic review and meta-analysis

PURPOSE

To provide contemporary and future estimates of childhood myopia prevalence in Africa.

METHODS

A systematic online literature search was conducted for articles on childhood (≤18 years) myopia (spherical equivalent [SE] ≤ -0.50D; high myopia: SE ≤ -6.00D) in Africa. Population- or school-based cross-sectional studies published from 1 Jan 2000 to 30 May 2021 were included. Meta-analysis using Freeman-Tukey double arcsine transformation was performed to estimate the prevalence of childhood myopia and high myopia. Myopia prevalence from subgroup analyses for age groups and settings were used as baseline for generating a prediction model using linear regression.

RESULTS

Forty-two studies from 19 (of 54) African countries were included in the meta-analysis (N = 737,859). Overall prevalence of childhood myopia and high myopia were 4.7% (95% CI: 3.3%-6.5%) and 0.6% (95% CI: 0.2%-1.1%), respectively. Estimated prevalence across the African regions was highest in the North (6.8% [95% CI: 4.0%-10.2%]), followed by Southern (6.3% [95% CI: 3.9%-9.1%]), East (4.7% [95% CI: 3.1%-6.7%]) and West (3.5% [95% CI: 1.9%-6.3%]) Africa. Prevalence from 2011 to 2021 was approximately double that from 2000 to 2010 for all studies combined, and between 1.5 and 2.5 times higher for ages 5-11 and 12-18 years, for boys and girls and for urban and rural settings, separately. Childhood myopia prevalence is projected to increase in urban settings and older children to 11.1% and 10.8% by 2030, 14.4% and 14.1% by 2040 and 17.7% and 17.4% by 2050, respectively; marginally higher than projected in the overall population (16.4% by 2050).

CONCLUSIONS

Childhood myopia prevalence has approximately doubled since 2010, with a further threefold increase predicted by 2050. Given this trajectory and the specific public health challenges in Africa, it is imperative to implement basic myopia prevention programmes, enhance spectacle coverage and ophthalmic services and generate more data to understand the changing myopia epidemiology to mitigate the expanding risk of the African population.

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.

Orthokeratology Lens Wear for 2 Years in Children Did Not Alter Tear Film Lipid Thickness by Non-Invasive Interferometry

Purpose

Previous studies suggest that overnight orthokeratology (OOK) may be detrimental to tear function. We aimed to investigate the effect of OOK on lipid layer thickness (LLT), blink pattern, and meibomian gland and elucidate the relationship of these variables.

Methods

Thirty-seven participants who wore OOK lenses every night for at least 2 years and twenty-four healthy non-contact lens wearers (controls) were enrolled in this retrospective study. LipiView interferometry, blink pattern analysis, the ocular surface status, and morphology and function of the meibomian gland were determined.

Results

The OOK group and healthy controls had similar LLT, blink patterns, ocular surface status, and the function of the meibomian gland. OOK participants demonstrated higher meiboscore in the lower eyelids (p < 0.05) but not in the upper eyelids. Within the OOK group, LLT was significantly impacted by the partial blink rate (p < 0.05) and the total score of the upper meibomian gland (p = 0.10).

Conclusions

Wearing OOK for 2 or more years increased lower eyelid meibomian gland dropout but did not have a reduction of LLT.

Prevalence of refractive errors among school students in Ethiopia: A systematic review and meta-analysis

Objective:

Refractive errors are most common ocular disorders among children and adolescents. They remain as secondary causes of avoidable blindness in impoverished areas in Africa, most notably in Ethiopia. The problem worsens if it is not managed and addressed early. The aim of this systematic review and meta-analysis was to determine the prevalence of refractive errors among school students in Ethiopia.

Methods:

We searched international databases such as PubMed/Medline, Web of Science, CINAHL, Embase, Scopus, Cochrane Library, Google Scholar, and Science Direct for relevant articles. Data were extracted using Microsoft Excel and exported to Stata version 14.0 software for analysis. The Cochrane Q and I2 tests were used to assess heterogeneity. Funnel plot, Egger’s, and Begg’s tests were used to assess reporting bias. Random effect meta-analysis model was employed to estimate pooled prevalence of refractive errors. A regional subgroup analysis was carried out.

Results:

We reviewed 22 qualified studies with 23,355 study participants. The overall prevalence of refractive errors among school students was 7.36% (95% confidence interval = 6.05, 8.67). The prevalence of myopia, hyperopia, and astigmatism was 5.10% (95% confidence interval = 3.79, 6.40), 0.95% (95% confidence interval = 0.59, 1.31), and 0.01% (95% confidence interval = 0.01, 0.04), respectively. From subgroup analysis, the highest prevalence of refractive errors was reported in Amhara Region (9.18%, 95% confidence interval = 6.63, 11.74), followed by Southern Nations, Nationalities, and Peoples’ region (6.78%, 95% confidence interval = 4.65, 8.92) while the lowest prevalence of refractive errors was reported in Addis Ababa (3.93%, 95% confidence interval = 3.30, 4.56).

Conclusion:

In Ethiopia, the prevalence of refractive errors among school students is higher (7.36%) compared to what it was 5 years (7.05%) ago. Amhara Region has the highest prevalence of refractive errors among school students in Ethiopia with myopia being the most common type of refractive error.

Effect of Sunshine Duration on Myopia in Primary School Students from Northern and Southern China

Background

To assess the current myopia prevalence rate and evaluate the effect of sunshine duration on myopia among primary school students in the north and south of China.

Methods

This prospective cross-sectional study pooled data from 9171 primary school students (grades from 1 to 6) from four cities in the north and south of China. National Geomatics Center of China (NGCC) and China Meteorological Administration provided data about altitude, latitude, longitude, average annual temperature, and average annual sunshine duration. Non-cycloplegic refraction was recorded, and prevalence rates in primary school students and factors associated with myopia were analyzed. Univariate and multivariate logistic regression models were used to determine the independent association of risk factors of myopia.

Results

The overall myopia prevalence was 28.0%, from 7.5% to 50.6% for first and sixth grades, respectively. Low, moderate and high myopia significantly increased with school grades from 7.30% to 35.0%, 0.3% to 13.60% and 0.00% to 1.9%, respectively. Multiple regression analysis revealed that longer average cumulative daylight hours were connected to lower myopia prevalence in primary school students (OR, 0.721; 95% CI, [0.593–0.877]; P=0.001), whereas girls and higher grade was independently associated with higher myopia prevalence (girls: β=0.189; OR, 1.208; 95% CI, [1.052–1.387]; P=0.007; higher grade: β=0.502; OR, 1.652; 95% CI, [1.580–1.726]; P<0.001).

Conclusion

This study demonstrated that myopia was highly prevalent in southern Chinese cities over northern ones, linked to shorter light exposure, higher education level, and female gender. Such findings reinforced the beneficial impact of daylight exposure with a protective role against myopia development.