Myopia progression varies with age and severity of myopia

Retinoscopes: Past and present

BACKGROUND

Retinoscopy is arguably the most important method in the eye clinic for diagnosing and managing refractive errors. Advantages of retinoscopy include its non-invasive nature, ability to assess patients of all ages, and usefulness in patients with limited cooperation or communication skills.

AIM

To discuss the history of retinoscopes and examine current literature on the subject.

METHODS

A search was conducted on the PubMed and with the reference citation analysis (https://www.referencecitationanalysis.com) database using the term “Retinoscopy,” with a range restricted to the last 10 years (2013-2023). The search string algorithm was: "Retinoscopy" (MeSH Terms) OR "Retinoscopy" (All Fields) OR "Retinoscopes" (All Fields) AND [(All Fields) AND 2013: 2023 (pdat)].

RESULTS

This systematic review included a total of 286 records. Publications reviewed iterations of the retinoscope into autorefractors, infrared photo retinoscope, television retinoscopy, and the Wifi enabled digital retinoscope.

CONCLUSION

The retinoscope has evolved significantly since its discovery, with a significant improvement in its diagnostic capabilities. While it has advantages such as non-invasiveness and broad applicability, limitations exist, and the need for skilled interpretation remains. With ongoing research, including the integration of artificial intelligence, retinoscopy is expected to continue advancing and playing a vital role in eye care.

Incidence of myopia in Swedish schoolchildren: A longitudinal study

PURPOSE

The prevalence of myopia in Scandinavia tends to be lower than in other parts of the world. This study aimed to investigate the incidence of myopia and its predictors in Swedish children to characterise this trend.

METHODS

A 2-year longitudinal study was conducted following a cohort of schoolchildren aged 8-16 years. Myopia was defined as a spherical equivalent refraction (SER) ≤ -0.50 D. The study enrolled 128 participants, 70 (55%) females with a mean age of 12.0 years (SD = 2.4).

RESULTS

The cumulative incidence of myopia during the follow-up period was 5.5%, and the incidence rate of myopia was 3.2 cases per 100 person-years. Participants with myopia at baseline exhibited a faster increase in refractive error during the follow-up period. Likewise, participants with two myopic parents exhibited a more marked change towards myopia, regardless of their initial refractive error.

CONCLUSION

In the current study, similar to prevalence, the incidence of myopia was low when compared with other parts of the world. These results lead us to formulate a new hypothesis that the normal emmetropisation process may be protected by low educational pressure practised in Sweden during early childhood. Further research is necessary to test this new hypothesis.

A review of mechanism of action of outdoor exposure in preventing myopia incidence and progression

Various studies have suggested several environmental, pharmacological, medical, and optical interventions and some are in use but their efficacy in myopia control may be transient, and the cellular, molecular, and biochemical mechanisms involved unclear. Daylight exposure is currently regarded as an effective and enduring strategy in the control of myopia development and progression. However, the mechanism behind the effect of outdoor exposure and its association with genetic predisposition and other relatively more significant environmental factors on myopia is still a conundrum. This review focuses on survey-based and intervention-based studies carried out to propose a mechanism that accounts for myopia development and important for its control.

Association Between Serum Vitamin D Levels and Myopia in the National Health and Nutrition Examination Survey (2001-2006)

PURPOSE

To assess the relationship between serum vitamin D levels and myopia in people aged 12-50 years using the National Health and Nutrition Examination Survey (NHANES) database.

METHODS

Demographics, vision, and serum vitamin D levels from NHANES (2001-2006) were analyzed. Multivariate analyses were performed to examine the relationship between serum vitamin D levels and myopia while controlling for sex, age, ethnicity, education level, serum vitamin A, and poverty status. The main outcome was presence or absence of myopia, defined as a spherical equivalent of -1 diopters or more.

RESULTS

Of the 11669 participants, 5,310 (45.5%) had myopia. The average serum vitamin D concentration was 61.6 ± 0.9 nmol/L for the myopic group and 63.1 ± 0.8 nmol/L for the non-myopic group (p = .01). After adjusting for all covariates, having higher serum vitamin D was associated with lower odds of having myopia (odds ratio 0.82 [0.74-0.92], p = .0007). In linear regression modeling that excluded hyperopes (spherical equivalent > +1 diopters), there was a positive relationship between spherical equivalent and serum vitamin D levels. Specifically, as serum vitamin D doubled, spherical equivalent increased by 0.17 (p = .02) indicating a positive dose-response relationship between vitamin D and myopia.

CONCLUSIONS

Participants with myopia, on average, had lower serum concentrations of vitamin D compared to those without myopia. While further studies are needed to determine the mechanism, this study suggests that higher vitamin D levels are associated with lower incidence of myopia.

The CroMyop study: myopia progression in Croatian children and adolescents-a 15-year retrospective analysis

Purpose

Myopia is a major global health issue, especially among children and adolescents. Understanding its traits and progression is vital for proper management and prevention. This study aimed to fill a gap in research by analyzing demographic and refractive data concerning myopia among children and adolescents in Croatia, with the goal of providing insights into myopia prevalence, progression rates, and associated risk factors within the Croatian population.

Design

This retrospective study utilized a comprehensive dataset from pediatric ophthalmology clinics at the University Eye Department, University Hospital "Sveti Duh," Zagreb, Croatia. The dataset included electronic medical records spanning from January 2008 to July 2023, encompassing demographic and refractive data.

Methods

Data analysis focused on individuals aged 4 to 18 years who were diagnosed with primary myopia and/or compound myopic astigmatism. Ophthalmic examinations, including visual acuity tests, cycloplegic refraction, and assessments for eye comorbidities, were conducted by experienced pediatric ophthalmologists. Statistical analysis, including t-tests, survival analysis, and logistic regression, was performed to assess myopia prevalence, progression rates, and associated factors. These analyses were adjusted for covariates such as age, parental myopia, and gender.

Results

The study included 895 individuals, 51 premyopes, 813 low myopes, and 31 high myopes. The average age of diagnosis was 11.37 ± 3.59 years for premyopes, 11.18 ± 3.53 years for low myopes, and 11.44 ± 4.35 years for high myopes. The fastest progression occurred in 2021 and 2022, -0.5 ± 0.12 D/y for premyopes and - 0.45 ± 0.1 D/y for low myopes. Premyopic progression to low myopia was associated with age 7-9 years (HR 2.42, 1.53 to 3.21) and both parents being myopic (HR 920.27. 850.16 to 950.53). Low myopic individuals with both myopic parents displayed the fastest 11-24 months after first visit progression rates, -0.69 (-0.52 to -0.87) D/y, while the 7-9 age group demonstrated -0.36 (-0.24 to -0.45) D/y. Low myopes aged 7-9 years with baseline SE between -6 D and -4 D were more strongly associated with ≤ - 0.5 D progression (OR = 2.0, 95% CI -1.00 to 2.39).

Conclusion

This study highlights the importance of environmental factors, genetics, and age in addressing myopia progression among Croatian youth, urging further research for effective local intervention strategies.

Light exposure profiles differ between myopes and non-myopes outside school hours

PURPOSE

Considering the putative role of light in myopia, and variations in socioeconomic, lifestyle, educational and environmental factors across ethnicities, we objectively investigated light exposure patterns in Indian school children.

METHODS

The light exposure profile of 143 school children (9-15 years, 50 myopes) recorded using a validated wearable light tracker for six continuous days was analysed. Additional data for non-school days were available for 87 children (26 myopes). The illuminance exposure levels, time spent outdoors and epoch (number of times participant is exposed to a predefined range of lux level per day) were compared between myopes and non-myopes across different light conditions: ≥1000, ≥3000, ≥5000 and ≥10 000 lux. For school days, light exposure profiles during (1) before school, school and after school hours; and (2) class, break and transition (when a student travels to and from school) time were analysed.

RESULTS

The overall median (IQR) daily illuminance exposure level, time spent outdoors and epochs at outdoors (≥1000 lux) were 807 (507-1079) lux/day, 46 (30-64) min/day and 9 (6-12) times/day, respectively. The daily illuminance exposure on non-school days was significantly higher in non-myopes than myopes (6369 (4508-9112) vs 5623 (2616-6929) lux/day, p=0.04). During transition time (school days), non-myopes had significantly higher illuminance exposure (910 (388-1479) vs 550 (263-1098) lux/day, p=0.04), spent more time outdoors (25 (10-43) vs 14 (4-29) min/day, p=0.01) and had higher outdoor epochs (6 (4-11) vs 5 (2-8) times/day, p=0.01) than myopes.

CONCLUSIONS

A small but significant difference in illuminance exposure, time spent outdoors and epoch was noted between myopes and non-myopes during transition time, which may have implications in myopia control.

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.

Randomised clinical trial of extended depth of focus lenses for controlling myopia progression: Outcomes from SEED LVPEI Indian Myopia Study

PURPOSE

To determine the efficacy of extended depth of focus (EDOF) contact lenses for controlling myopia progression in children through a 1-year randomised clinical trial.

METHODS

A total of 104 children aged 7-15 years, with spherical equivalent refraction ≤-0.50 D, were randomly assigned to wear SEED 1 dayPure EDOF Mid contact lenses (n=48) or single vision spectacle lenses (n=56). Cycloplegic refraction with Shin-Nippon open field autorefractor and axial length with Lenstar LS 900 was determined at the baseline and 12-month visits. The compliance, visual discomfort and dryness questionnaires were administered during the final visit.

RESULTS

Sixty-nine children (control: n=38; treatment: 31) completed the 12-month follow-up visit, with no difference in baseline characteristics between the groups. Mean (SEM) myopia progression in the 12th month was -0.48±0.07D in the control group and -0.20±0.08D in the treatment group. Mean axial elongation was 0.22±0.03 mm and 0.11±0.03 mm in the control and treatment groups, respectively. SEED 1 dayPure EDOF Mid contact lenses slowed myopia progression by 59% (-0.28D; p=0.01) based on spherical equivalent refraction and controlled axial length by 49% (0.11 mm; p=0.007) in comparison to single vision spectacle lenses. None of the participants reported any adverse effects. While most of the participants (82%) were comfortable with the contact lenses, 11% reported occasional dryness and 14% experienced mild fluctuations in visual acuity after immediate lens wear.

CONCLUSION

Daily wear of SEED 1 dayPure EDOF Mid contact lenses in Indian children showed a significant effect in controlling myopia progression and axial elongation.

A retrospective study of cumulative absolute reduction in axial length after photobiomodulation therapy

BACKGROUND

To assess the age and timeline distribution of ocular axial length shortening among myopic children treated with photobiomodulation therapy in the real world situations.

METHODS

Retrospective study of photobiomodulation therapy in Chinese children aged 4 to 13 years old where axial length measurements were recorded and assessed to determine effectiveness at two age groups (4 ∼ 8 years old group and 9 ∼ 13 years old group). Data was collected from myopic children who received photobiomodulation therapy for 6 ∼ 12 months. Effectiveness of myopia control was defined as any follow-up axial length ≤ baseline axial length, confirming a reduction in axial length. Independent t-test was used to compare the effectiveness of the younger group and the older group with SPSS 22.0.

RESULTS

342 myopic children were included with mean age 8.64 ± 2.20 years and baseline mean axial length of 24.41 ± 1.17 mm. There were 85.40%, 46.30%, 71.20% and 58.30% children with axial length shortening recorded at follow-up for 1 month, 3 months, 6 months and 12 months, respectively. With respect to the axial length shortened eyes, the mean axial length difference (standard deviation) was - 0.039 (0.11) mm, -0.032 (0.11) mm, -0.037 (0.12) mm, -0.028 (0.57) mm at 1, 3, 6, and 12-month follow-up, respectively. Greater AL shortening was observed among the older group who had longer baseline axial lengths than the younger group (P < 0.001).

CONCLUSIONS

Overall myopia control effectiveness using photobiomodulation therapy was shown to be age and time related, with the maximum absolute reduction in axial elongation being cumulative.

Astigmatism and maternal myopia as important factors affecting success rate of DIMS lens treatment

OBJECTIVE

To assess the efficacy of myopia control spectacle lenses (defocus incorporated multiple segments/DIMS) in slowing myopia progression among a diverse Central European paediatric population and investigate the contribution of baseline parameters on treatment outcomes.

METHODS AND ANALYSIS

This retrospective observational study included 62 individuals aged 4-17 years (mean±SD: 10.21±2.70) with progressing myopia but without ocular pathology with a range of -0.88 to -8.25 D spherical equivalent refraction (SER) (-3.73±1.56), coupled with astigmatism up to -3.25 D cylindrical. All participants were prescribed DIMS (Hoya MiyoSmart) spectacles. Key outcome variables were cycloplegic SER, measured for all participants and axial length (AL), assessed in a subset of patients, recorded at baseline, 6 months and 12 months. Quality of life assessments were conducted at baseline, at 2 weeks, and 3, 6, 9 and 12 months. Additionally, parental myopic dioptre was recorded when applicable.

RESULTS

At the 12-month mark, myopia progression in patients (mean±SE: -0.40±0.05) mirrored findings from prior European DIMS studies, but with 50% of patients showing no progression. A multivariate analysis of covariance model revealed that baseline astigmatism and younger age adversely affected therapy outcomes in both SER and AL, while severe maternal myopia led to greater SER progression. In contrast, only young age but not astigmatism was associated with AL increase in a comparable group of children with myopia, part of the LIFE Child Study, wearing single-vision spectacles. Patients reported consistent satisfaction with treatment, with minimal side effects, which diminished over the year.

CONCLUSION

In the European population, astigmatism, young age and severe maternal myopia are risk factors for suboptimal outcomes following DIMS therapy. Further research is necessary to elucidate the impact of astigmatism on myopic defocus therapy.

Myopia progression patterns among paediatric patients in a clinical setting

PURPOSE

This retrospective analysis of electronic medical record (EMR) data investigated the natural history of myopic progression in children from optometric practices in Ireland.

METHODS

The analysis was of myopic patients aged 7-17 with multiple visits and not prescribed myopia control treatment. Sex- and age-specific population centiles for annual myopic progression were derived by fitting a weighted cubic spline to empirical quantiles. These were compared to progression rates derived from control group data obtained from 17 randomised clinical trials (RCTs) for myopia. Linear mixed models (LMMs) were used to allow comparison of myopia progression rates against outputs from a predictive online calculator. Survival analysis was performed to determine the intervals at which a significant level of myopic progression was predicted to occur.

RESULTS

Myopia progression was highest in children aged 7 years (median: -0.67 D/year) and progressively slowed with increasing age (median: -0.18 D/year at age 17). Female sex (p < 0.001), a more myopic SER at baseline (p < 0.001) and younger age (p < 0.001) were all found to be predictive of faster myopic progression. Every RCT exhibited a mean progression higher than the median centile observed in the EMR data, while clinic-based studies more closely matched the median progression rates. The LMM predicted faster myopia progression for patients with higher baseline myopia levels, in keeping with previous studies, which was in contrast to an online calculator that predicted slower myopia progression for patients with higher baseline myopia. Survival analysis indicated that at a recall period of 12 months, myopia will have progressed in between 10% and 70% of children, depending upon age.

CONCLUSIONS

This study produced progression centiles of untreated myopic children, helping to define the natural history of untreated myopia. This will enable clinicians to better predict both refractive outcomes without treatment and monitor treatment efficacy, particularly in the absence of axial length data.

Study of myopia progression and risk factors in Hubei children aged 7-10 years using machine learning: a longitudinal cohort

BACKGROUND

To investigate the trend of refractive error among elementary school students in grades 1 to 3 in Hubei Province, analyze the relevant factors affecting myopia progression, and develop a model to predict myopia progression and the risk of developing high myopia in children.

METHODS

Longitudinal study. Using a cluster-stratified sampling method, elementary school students in grades 1 to 3 (15,512 in total) from 17 cities in Hubei Province were included as study subjects. Visual acuity, cycloplegic autorefraction, and height and weight measurements were performed for three consecutive years from 2019 to 2021. Basic information about the students, parental myopia and education level, and the students' behavioral habits of using the eyes were collected through questionnaires.

RESULTS

The baseline refractive errors of children in grades 1 ~ 3 in Hubei Province in 2019 were 0.20 (0.11, 0.27)D, -0.14 (-0.21, 0.06)D, and - 0.29 (-0.37, -0.22)D, respectively, and the annual myopia progression was - 0.65 (-0.74, -0.63)D, -0.61 (-0.73, -0.59)D and - 0.59 (-0.64, -0.51)D, with the prevalence of myopia increasing from 17.56%, 20.9%, and 34.08% in 2019 to 24.16%, 32.24%, and 40.37% in 2021 (Χ2 = 63.29, P < 0.001). With growth, children's refractive error moved toward myopia, and the quantity of myopic progression gradually diminished. (F = 291.04, P = 0.027). The myopia progression in boys was less than that in girls in the same grade (P < 0.001). The change in spherical equivalent refraction in myopic children was smaller than that in hyperopic and emmetropic children (F = 59.28, P < 0.001), in which the refractive change in mild myopia, moderate myopia, and high myopia children gradually increased (F = 73.12, P < 0.001). Large baseline refractive error, large body mass index, and high frequency of eating sweets were risk factors for myopia progression, while parental intervention and strong eye-care awareness were protective factors for delaying myopia progression. The nomogram graph predicted the probability of developing high myopia in children and found that baseline refraction had the greatest predictive value.

CONCLUSION

Myopia progression varies by age, sex, and myopia severity. Baseline refraction is the most important factor in predicting high myopia in childhood. we should focus on children with large baseline refraction or young age of onset of myopia in clinical myopia prevention and control.

Lifestyle Factors in Myopic Spanish Children

BACKGROUND

Childhood myopia represents a global concern with increasing prevalence in recent decades. Lifestyle factors significantly impact myopia.

AIM

To evaluate lifestyle factors in myopic children from a metropolitan area in Europe.

METHODS

This was a descriptive study including myopic subjects aged 4-18 years. Patient demographic and clinical data were collected, including cycloplegic refraction in spherical equivalent refraction (SER) and axial length (AL). In addition, a questionnaire on lifestyle factors was conducted between September 2022 and April 2023.

RESULTS

A total of 321 myopic children were included, aged 10.72 ± 3.05 years, of whom 51.4% were boys, with SER -2.25 ± 1.9 D and AL 24.54 ± 0.98 mm. The mean age of myopia onset was 7.69 ± 3.05 years. A total of 59.8% had family history of myopia. Those children who had <2 h/day of screen time (on weekdays) presented SER -2 ± 1.91 D, compared to those who had >2 h/day, SER: -2.50 ±1.88 D (p = 0.009). Children who spent <2 h/day doing near work after school were less myopic compared to those who spent >2 h/day (SER: -1.75 ± 1.83 vs. SER: -2.75 ± 1.82, respectively, p = 0.03). However, no significant association was observed between SER and AL and time spent outdoors nor between SER and AL and academic performance (p > 0.05).

CONCLUSIONS

Screen time and near-work time appear to be lifestyle factors related to myopia.

Correction Method for Optical Scaling of Fundoscopy Images: Development, Validation, and First Implementation

Purpose

Although fundus photography is extensively used in ophthalmology, refraction prevents accurate distance measurement on fundus images, as the resulting scaling differs between subjects due to varying ocular anatomy. We propose a PARaxial Optical fundus Scaling (PAROS) method to correct for this variation using commonly available clinical data.

Methods

The complete optics of the eye and fundus camera were modeled using ray transfer matrix formalism to obtain fundus image magnification. The subject's ocular geometry was personalized using biometry, spherical equivalent of refraction (RSE), keratometry, and/or corneal topography data. The PAROS method was validated using 41 different eye phantoms and subsequently evaluated in 44 healthy phakic subjects (of whom 11 had phakic intraocular lenses [pIOLs]), 29 pseudophakic subjects, and 21 patients with uveal melanoma.

Results

Validation of the PAROS method showed small differences between model and actual image magnification (maximum 3.3%). Relative to the average eye, large differences in fundus magnification were observed, ranging from 0.79 to 1.48. Magnification was strongly inversely related to RSE (R2 = 0.67). In phakic subjects, magnification was directly proportional to axial length (R2 = 0.34). The inverse relation was seen in pIOL (R2 = 0.79) and pseudophakic (R2 = 0.12) subjects. RSE was a strong contributor to magnification differences (1%-83%). As this effect is not considered in the commonly used Bennett-Littmann method, statistically significant differences up to 40% (mean absolute 9%) were observed compared to the PAROS method (P < 0.001).

Conclusions

The significant differences in fundus image scaling observed among subjects can be accurately accounted for with the PAROS method, enabling more accurate quantitative assessment of fundus photography.

Evaluating the Effect of a Myopia Control Spectacle Lens Among Children in Israel: 12-Month Results

PURPOSE

To investigate the effectiveness of a novel spectacle lens designed to slow the progression of myopia in children.

DESIGN

A prospective, randomized, double blind clinical trial.

METHODS

One hundred twenty-six Israeli children aged 6-13 years with spherical equivalent (SER) refractive errors of -0.5 to -6.25 diopters (D) were randomized into either the Shamir Myopia Control (SMC) lens design group or the conventional single-vision spectacle lenses (SVL), the control group. Outcomes measured were changes in axial length and cycloplegic refraction as well as subjective rating of visual experience over a period of 12 months.

RESULTS

At 12 months, AL and SER progression were slowed by 0.11 mm (35%, P < .05) and 0.16 D (25%, P = .122), respectively. In the subgroup of 6-10-year-olds, AL and SER progression were slowed by 0.17 mm (41%, P < .05) and 0.31 D (43%, P < .05), respectively. Similarly, for the subgroup of children with 2 myopic parents AL and SER progression were slowed by 0.15 mm (45% P < .05) and 0.36 D (42%, P < .05), respectively. Subjective visual experience reported in the 12-month questionnaire revealed no difference between the SMC and SVL groups, and average daily wearing hours were also not different between the groups: 14 (±1.4) and 13.8 (±2.3) hours, respectively. The study continues to its second year.

CONCLUSIONS

SMC lenses were effective in slowing the progression of SER and AL, especially for younger children and those having 2 myopic parents. The subjective rating of visual experience and the daily duration of use reported by the SMC group at 12 months were similar to the control group, indicating good lens tolerability.

Refractive Error among Children Visiting the Department of Paediatric Opthalmology of a Tertiary Eye Care Center

Introduction

Refractive error is the inability of eyes to focus clearly on images. Visual impairment due to refractive error has a major impact on children's education and daily activities. The hospital has no documentation of the ocular morbidity related to refractive errors in children. The aim of this study was to find out the prevalence of refractive error in children visiting the Department of Paediatric Ophthalmology of a tertiary care centre.

Methods

A descriptive cross-sectional study was done in the Outpatient Department of Paediatric Ophthalmology in a tertiary care centre from 8 September 2022 to 7 March 2023 after obtaining ethical approval from the Institutional Review Committee. A convenience sampling method was used. The point estimate was calculated at 95% Confidence Interval.

Results

Among 3600 children, the prevalence of refractive error was seen in 668 children (18.56%) (15.61-21.51, 95% Confidence Interval). Refractive error was seen in 363 (54.34%) boys and 305 (45.66%) girls. Myopia was found in 340 (50.90%), astigmatism in 207 (30.99%), and hyperopia in 121 (18.11%).

Conclusions

The prevalence of refractive error among children attending a tertiary care centre was found to be higher than studies done in similar settings. Regular screening of refractive error for visual impairment is recommended among school going children.

Keywords

astigmatism; hyperopia; myopia; refractive error; visual impairment.

The biology of aging in a social world: Insights from free-ranging rhesus macaques

Social adversity can increase the age-associated risk of disease and death, yet the biological mechanisms that link social adversities to aging remain poorly understood. Long-term naturalistic studies of nonhuman animals are crucial for integrating observations of social behavior throughout an individual's life with detailed anatomical, physiological, and molecular measurements. Here, we synthesize the body of research from one such naturalistic study system, Cayo Santiago, which is home to the world's longest continuously monitored free-ranging population of rhesus macaques (Macaca mulatta). We review recent studies of age-related variation in morphology, gene regulation, microbiome composition, and immune function. We also discuss ecological and social modifiers of age-markers in this population. In particular, we summarize how a major natural disaster, Hurricane Maria, affected rhesus macaque physiology and social structure and highlight the context-dependent and domain-specific nature of aging modifiers. Finally, we conclude by providing directions for future study, on Cayo Santiago and elsewhere, that will further our understanding of aging across different domains and how social adversity modifies aging processes.

Cost-Effectiveness Analysis of Myopia Progression Interventions in Children

Importance

Several interventions exist for treating myopia progression in children. While these interventions' efficacy has been studied, their cost-effectiveness remains unknown and has not been compared.

Objective

To determine cost-effective options for controlling myopia progression in children.

Design, Setting, and Participants

In this cost-effectiveness analysis, a Markov model was designed to compare the cost-effectiveness of interventions for controlling myopia progression over 5 years from a societal perspective in a simulated hypothetical cohort of patients aged 10 years with myopia. Myopia interventions considered included atropine eye drops, 0.05% and 0.01%, defocus incorporated multiple segment spectacles, outdoor activity, soft contact lenses (daily disposable and multifocal), rigid gas-permeable contact lenses, progressive addition lenses, bifocal spectacle lenses, orthokeratology, highly aspherical lenslets (HALs), and red light therapy; all interventions were compared with single-vision lenses. Deterministic and probabilistic sensitivity analysis determined the association of model uncertainties with the cost-effectiveness. Costs were obtained from the charges of the Hospital Authority of Hong Kong and The Chinese University of Hong Kong Eye Center.

Main Outcome and Measures

The mean costs (in US dollars) per child included the cost of hospital visits, medications, and optical lenses. The outcomes of effectiveness were the annual spherical equivalent refraction (SER) and axial length (AL) reductions. Incremental cost-effectiveness ratios (ICERs) were calculated for each strategy relative to single-vision lenses over a time horizon of 5 years.

Results

Outdoor activity, atropine (0.05%), red light therapy, HALs, and orthokeratology were cost-effective. The ICER of atropine, 0.05%, was US $220/SER reduction; red light therapy, US $846/SER reduction; and HALs, US $448/SER reduction. Outdoor activity yielded a savings of US $5/SER reduction and US $8/AL reduction. Orthokeratology resulted in an ICER of US $2376/AL reduction.

Conclusions and Relevance

These findings suggest that atropine eye drops, 0.05%, and outdoor activity are cost-effective for controlling myopia progression in children. Though more expensive, red light therapy, HALs, and orthokeratology may also be cost-effective. The use of these interventions may help to control myopia in a cost-effective way.

Real-world outcomes of low-dose atropine therapy on myopia progression in an Australian cohort during the COVID-19 pandemic

BACKGROUND

To report the outcomes of low-dose atropine (0.01% and 0.05%) for preventing myopia progression in a real-world Australian cohort during the COVID-19 pandemic.

METHODS

Records of children presenting with myopia, from January 2016 to 2022, were retrospectively reviewed at a comprehensive ophthalmic practice. Children who discontinued treatment, ages >18, and cases with hereditary conditions were excluded. The rate of progression of myopia after treatment with atropine was compared with historical data to evaluate the effectiveness of the regime.

RESULTS

One hundred and one children (mean baseline spherical equivalent [SphE] [-3.70 +/- 2.09 D] and axial length [AL] [24.59 +/- 1.00 mm]) were analysed. The mean age of the children was 10.4 +/- 2.89 years and 61% were females. The average follow-up time was 17.9 +/- 12.5 months. The mean rate of progression of AL and SphE on 0.01% atropine eyedrops was 0.219 +/- 0.35 mm and - 0.250 +/- 0.86 D/year, respectively. 68.1% of the children treated with 0.01% atropine were mild progressors (<0.5 D change/year). Non-responders when commenced on a higher dose of atropine (0.05%) experienced a 93% (p = 0.012) and 30% reduction in SphE and AL growth rate, respectively. Family history, higher myopia or younger age at baseline and shorter duration of treatment were associated with steeper progression (p < 0.01). Both doses were well tolerated.

CONCLUSIONS

Low-dose atropine was shown to be beneficial in a real-world clinical setting, despite interruptions to follow-ups secondary to COVID-19 pandemic. A 0.05% dose of atropine may be effective in cases where 0.01% was ineffective.

Safety and efficacy of 0.01% and 0.1% low-dose atropine eye drop regimens for reduction of myopia progression in Danish children: a randomized clinical trial examining one-year effect and safety

BACKGROUND

To investigate the efficacy and safety of 0.1% and 0.01% low-dose atropine eye drops in reducing myopia progression in Danish children.

METHODS

Investigator-initiated, placebo-controlled, double-masked, randomized clinical trial. Ninety-seven six- to twelve-year old myopic participants were randomized to 0.1% loading dose for six months followed by 0.01% for six months (loading dose group, Number (N) = 33), 0.01% for twelve months (0.01% group, N = 32) or vehicle for twelve months (placebo, N = 32). Primary outcomes were axial length and spherical equivalent refraction. Secondary outcomes included adverse events and reactions, choroidal thickness and ocular biometry. Outcomes were measured at baseline and three-month intervals. Data was analyzed with linear-mixed model analysis according to intention-to-treat.

RESULTS

Mean axial elongation was 0.10 mm less (95% confidence interval (CI): 0.17; 0.02, adjusted-p = 0.06) in the 0.1% loading dose and 0.07 mm less (95% CI: 0.15; 0.00, adjusted-p = 0.16) in the 0.01% group at twelve months compared to placebo. Mean spherical equivalent refraction progression was 0.24 D (95% CI: 0.05; 0.42) less in the loading dose and 0.19 D (95% CI: 0.00; 0.38) less in the 0.01% groups at twelve months, compared to placebo (adjusted-p = 0.06 and 0.14, respectively). A total of 108 adverse events were reported during the initial six-month loading dose period, primarily in the loading dose group, and 14 were reported in the six months following dose switching, all deemed mild except two serious adverse events, unrelated to the intervention.

CONCLUSIONS

Low-dose atropine eye drops are safe over twelve months in otherwise healthy children. There may be a modest but clinically relevant reduction in myopia progression in Danish children after twelve months treatment, but the effect was statistically non-significant after multiple comparisons adjustment. After dose-switching at six months the loading dose group approached the 0.01% group, potentially indicating an early "rebound-effect".

TRIAL REGISTRATION

this study was registered in the European Clinical Trials Database (EudraCT, number: 2018-001286-16) 05/11/2018 and first posted at www.

CLINICALTRIALS

gov (NCT03911271) 11/04/2019, prior to initiation.

The rate of orthokeratology lens use and associated factors in 33,280 children and adolescents with myopia: a cross-sectional study from Shanghai

OBJECTIVES

To investigate the rate of orthokeratology lens (ortho-k lens) use and its associated factors in children and adolescents with myopia.

METHODS

Cross-sectional study. Children from 104 primary and middle schools in Shanghai were enrolled by cluster sampling. Ophthalmic examinations were conducted and information was obtained using questionnaires for associated factors analysis.

RESULTS

A total of 72,920 children and adolescents were included, among which 32,259 were the potential population for ortho-k lens use. A total of 1021 participants used ortho-k lenses, equating to a use rate of 1.4% in the total population and 3.1% in the potential population. Age (OR 0.91, 95% CI: 0.88-0.95, p < 0.001), BMI (≥95th percentile: OR 0.48, 95% CI: 0.35-0.66, p < 0.001), age at initiation of refractive correction (≤12 years: OR 1.75, 95% CI: 1.31-2.33, p < 0.001), and parental myopia (either: OR 2.09, 95% CI: 1.58-2.75, p < 0.001; both: OR 3.94, 95% CI: 3.04-5.11, p < 0.001) were independently associated with ortho-k lens use. Of the ortho-k lenses users, 12.4% had a logMAR CVA of ≥0.3. A correction target (SE) of ≤-3.0 D (OR 2.05, 95% CI: 1.38-3.05, p < 0.001) and a sleeping duration of ≤6 h (OR 4.19, 95% CI: 2.03-8.64, p < 0.001) were factors independently associated with CVA ≥ 0.3.

CONCLUSIONS

A certain proportion of children and adolescents in Shanghai chose to wear ortho-k lenses, related to the situation of parents and children themselves. Health education and follow-ups should be strengthened to ensure orthokeratology application quality.

Progression pattern of non-amblyopic Anisomyopic eyes compared to Isomyopic eyes

This study aimed to determine the progression pattern of non-amblyopic anisomyopic children from ages 6 to 16 years. This retrospective study analyzed the electronic medical records of 8680 myopic children who visited Sankara Nethralaya, Chennai, India over eight years (2009 to 2017). A total of 711 records were retrieved based on inclusion criteria. In addition, 423 records out of 711 had consecutive follow-up for three years (baseline plus three follow-up visits) and were considered to determine the progression pattern. The cycloplegic sphero-cylindrical refraction was taken for analysis and converted to vector notation of M (SE), J0, and J45. Anisomyopia referred to the interocular difference of myopic SE of ≥ 1 D whereas isomyopia referred to the interocular difference of myopic SE of < 1 D. Based on the refraction of the less ametropic eye, anisomyopes were further categorized into bilateral anisometropic myopia (BAM) and unilateral anisometropic myopia (UAM). The isomyopic cohort showed a mean annual progression of -0.49 ± 0.54 D (median [IQR] -0.38 D [{-0.75}-0.00]). In BAM, the mean annual progression of the more myopic eye was -0.45 ± 0.55 D (median [IQR] -0.38 D [{-0.75}-0.00]), and the less myopic eye was -0.37 ± 0.55 D (median [IQR] -0.25 D [{-0.63}-0.00]). This difference was significant (t (212) = -2.14, p < 0.05). In UAM, the myopic eyes (-0.39 ± 0.51 D; median [IQR] -0.25 D [{-0.75}-0.00]) showed a statistically significant higher mean annual progression compared to emmetropic eyes (-0.22 ± 0.36 D; median [IQR] 0.00 D [{-0.44}-0.00]; t (96) = -3.30, p < 0.001). In terms of progression trend, in the BAM group, the rate of change of mean SE between the more myopic and the less myopic eyes were similar (-1.12 ± 1.20 D; median [IQR] -1.13 D [{-2.00}-{-0.38}] vs. -1.05 ± 1.25 D; median [IQR] -0.88 D [{-1.75}-{-0.13}]; t (138) = -0.64, p > 0.05). However, the more myopic eyes of UAM showed a higher myopic trend compared to the emmetropic eyes (-1.37 ± 1.06 D; median [IQR] -1.32 D [{-2.13}-{-0.50}] vs. -0.96 ± 1.11 D; median [IQR] -0.75 D [{-1.56}-{-0.25}]; t (61) = -2.74, p < 0.05).   Conclusion: Children with BAM and UAM eyes exhibit different progression patterns from each other. While the rate of the refractive shift in myopic eyes of UAM is similar to isomyopic eyes, BAM eyes present a slower rate of progression than isomyopic eyes. What is Known: • The rate of change of refraction in anisomyopes is higher compared to isomyopic children. • Less myopic eyes tend to shift towards more myopia while more myopic eyes show stable refraction. What is New: • The progression pattern of bilateral anisometropic myopia and unilateral anisometropic myopia differ from one another. • While the rate of the refractive shift in myopic eyes of unilateral anisometropic myopia is similar to isomyopic eyes, bilateral anisometropic myopia eyes present a slower rate of progression than isomyopic eyes. • The pattern of change in the interocular difference of anisometropia depends on the laterality (bilateral or unilateral ametropia), and degree of spherical equivalent in the more ametropic eye.

Establishment and validation of a risk assessment model for myopia among Chinese primary school students during the COVID-19 pandemic: A lasso regression approach

Purpose

To construct a risk assessment model for forecasting the likelihood of myopia in elementary school students.

Design

A cross-sectional study.

Methods

This study utilized convenient sampling and questionnaire survey to collect data from eligible elementary students and their parents during the coronavirus disease 2019 (COVID-19) pandemic period from March to December 2020. The data were divided into training and testing sets in a 7:3 ratio. Lasso regression was employed to screen variables for inclusion in the model to establish a generalized linear model, with a nomogram model as the final result.

Results

The study included 1139 elementary students, comprising 54.5 % male and 45.5 % female participants. A total of 37 variables were obtained, which were analyzed using lasso regression. Cross-validation revealed that the best lambda value was 0.04201788. Five variables affecting myopia were identified: three risk and two protective factors. The three risk factors were student age (OR = 1.32), family location (urban vs. rural, OR = 2.33), and parents' occupation (compared with farmer: worker, OR = 2.03; teacher, OR = 1.62; medical worker, OR = 5.64; self-employed, OR = 1.78; civil servant, OR = 1.65; company employee, OR = 1.45; service industries, OR = 3.38; and others, OR = 3.20). The two protective factors were eye distance score (OR = 0.83) and eye health exercise score (OR = 0.95). The model was verified and showed good accuracy with an AUC of 0.778 and Brier score of 0.122 in addition to satisfactory clinical effects.

Conclusions

The model effectively predicted the risk of myopia in elementary school students during the COVID-19 pandemic. Using this model, high-risk groups can be identified to provide a foundation for early intervention and follow-up, thereby reducing the incidence of myopia in this population.

Investigation of Choroidal Blood Flow and Thickness Changes Induced by Near Work in Young Adults

PURPOSE

This research aimed to determine the effects of near work on macular choroidal blood flow and thickness in young adults.

METHODS

A total of 109 participants (19-28 years old) were recruited from Capital Medical University in China. The participants spent 40 min reading a book text at a distance of 33 cm. Swept-source optical coherence tomography/optical coherence tomography angiography (SS-OCT/OCTA) was performed to measure the changes in choriocapillaris perfusion area (CCPA) and choroidal thickness (ChT) after 40 min of near work. The SS-OCT/OCTA data covered an area of 6 mm × 6 mm, which centered on the fovea.

RESULTS

The baseline ChT and CCPA before near work were negatively correlated with AL, while positively correlated with the magnitude of spherical equivalent (p < .001). Total CCPA decreased significantly by 6 mm × 6 mm macular area after near work compared to that before near work (24.26 ± 1.96 vs. 24.63 ± 1.61 mm2, p<.001). The macular ChT was lower after 40 min of reading than that before 40 min of reading, but no significant difference was observed (302.25 ± 77.69 vs. 304.92 ± 79.73 μm, p = .078). The extent of choroidal thinning was significantly positively correlated with the magnitude of CCPA reduction (p < .001). The decline in CCPA after near work was significantly positively correlated with axial length (AL; p < .001).

CONCLUSION

This study demonstrated that near work significantly decreased CCPA. The extent of CCPA reduction after near work was associated with higher severity of myopia and choroidal thinning. The baseline CCPA and ChT decreased gradually with AL.

Longitudinal Changes in Axial Length and Spherical Equivalent in Children and Adolescents With High Myopia

Purpose

To investigate longitudinal changes in axial length (AL) and spherical equivalent (SE) in children and adolescents with high myopia and to explore associated risk factors.

Methods

This was a longitudinal, observational cohort study of highly myopic participants (aged 7-17 years) to evaluate the mean rates of change in AL and SE. Mixed effects regression models were used to explore the risk factors.

Results

The sample consisted of 293 participants (mean age at the baseline, 13.63 ± 2.66 years; mean AL, 27.03 ± 1.30 mm diopters; mean SE, -8.99 ± 2.30 diopters) who were followed for 7.09 ± 1.64 years. Pathological myopia (PM) was present in 11.95% of the participants at the baseline. Over the follow-up period, the mean AL and SE progression rates were 0.13 mm/y (95% CI, 0.12-0.14) and -0.36 diopters/y (95% CI, -0.39 to -0.34). The multivariate analysis showed that the AL elongation and myopic SE progression decreased significantly after age 11 (β = -0.080, P < 0.001; β = 0.146, P < 0.001), increased with a greater baseline SE (β = -0.006, P = 0.014; β = 0.017, P = 0.005), and accelerated in children and adolescents who had PM at the baseline (β = 0.043, P = 0.011; β = -0.097, P = 0.025).

Conclusions

A significant association was found between acceleration of AL elongation and myopic SE progression among the children and adolescents with age, especially those younger than 11 years, and the presence of PM.

Distribution of Axial Length in Australians of Different Age Groups, Ethnicities, and Refractive Errors

Purpose

Treatments are available to slow myopic axial elongation. Understanding normal axial length (AL) distributions will assist clinicians in choosing appropriate treatment for myopia. We report the distribution of AL in Australians of different age groups and refractive errors.

Methods

Retrospectively collected spherical equivalent refraction (SER) and AL data of 5938 individuals aged 5 to 89 years from 8 Australian studies were included. Based on the SER, participants were classified as emmetropes, myopes, and hyperopes. Two regression model parameterizations (piece-wise and restricted cubic splines [RCS]) were applied to the cross-sectional data to analyze the association between age and AL. These results were compared with longitudinal data from the Raine Study where the AL was measured at age 20 (baseline) and 28 years.

Results

A piece-wise regression model (with 1 knot) showed that myopes had a greater increase in AL before 18 years by 0.119 mm/year (P < 0.001) and after 18 years by 0.011 mm/year (P < 0.001) compared to emmetropes and hyperopes, with the RCS model (with 3 knots) showing similar results. The longitudinal data from the Raine Study revealed that, when compared to emmetropes, only myopes showed a significant change in the AL in young adulthood (by 0.016 mm/year, P < 0.001).

Conclusions

The AL of myopic eyes increases more rapidly in childhood and slightly in early adulthood. Further studies of longitudinal changes in AL, particularly in childhood, are required to guide myopia interventions.

Translational Relevance

The axial length of myopic eyes increases rapidly in childhood, and there is a minimal increase in the axial length in non-myopic eyes after 18 years of age.

Prevention and management of childhood progressive myopia: National consensus guidelines

Myopia is a major public health problem worldwide, including India, with the global prevalence of myopia increasing rapidly over decades. The clinical and socioeconomic impact of myopia is also expected to rise with rising prevalence. Therefore, the focus has now been shifted to prevent the incidence and progression of myopia. However, there is lack of any standardized guidelines for myopia management. This document aims to generate a national-level expert consensus statement on the management of childhood myopia in the Indian scenario. The expert panel of pediatric ophthalmologists consisted of 63 members who met in a hybrid meeting. A list of topics deliberating discussion in the meeting was provided to the experts in advance and they were instructed to provide their opinions on the matter during the meet. The panel of experts then gave their views on each of the items presented, deliberated on different aspects of childhood myopia, and reached a consensus regarding the practice patterns in the Indian scenario. In case of opposing views or lack of a clear consensus, we undertook further discussion and evaluated literature to help arrive at a consensus. A written document is prepared based on recommendations explaining definition of myopia, refraction techniques, components and methods of workup, initiation of anti-myopia treatment, type and timing of interventions, follow-up schedule, and indications for revised or combination treatment. This article formulates evidence-based guidelines for progressing myopes and pre-myopes and also establishes uniformity in the management of childhood myopia in the country.

Myopia progression risk assessment score (MPRAS): a promising new tool for risk stratification

Timely identification of individuals "at-risk" for myopia progression is the leading requisite for myopia practice as it aids in the decision of appropriate management. This study aimed to develop 'myopia progression risk assessment score' (MPRAS) based on multiple risk factors (10) to determine whether a myope is "at-risk" or "low-risk" for myopia progression. Two risk-score models (model-1: non-weightage, model-2: weightage) were developed. Ability of MPRAS to diagnose individual "at-risk" for myopia progression was compared against decision of five clinicians in 149 myopes, aged 6-29 years. Using model-1 (no-weightage), further 7 sub-models were created with varying number of risk factors in decreasing step-wise manner (1a: 10 factors to 1g: 4 factors). In random eye analysis for model-1, the highest Youden's J-index (0.63-0.65) led to the MPRAS cut-off score of 41.50-43.50 for 5 clinicians with a sensitivity ranging from 78 to 85% and specificity ranging from 79 to 87%. For this cut-off score, the mean area under the curve (AUC) between clinicians and the MPRAS model ranged from 0.89 to 0.90. Model-2 (weighted for few risk-factors) provided similar sensitivity, specificity, and AUC. Sub-model analysis revealed greater AUC with high sensitivity (89%) and specificity (94%) in model-1g that has 4 risk factors compared to other sub-models (1a-1f). All the MPRAS models showed good agreement with the clinician's decision in identifying individuals "at-risk" for myopia progression.

Effectiveness of 0.01% atropine in anisomyopic children

Purpose

To investigate the change in ocular parameters of anisomyopic children treated with 0.01% atropine.

Methods

This retrospective study analyzed the data of anisomyopic children who underwent comprehensive examination at a tertiary eye center in India. Anisomyopic subjects (difference of ≥1.00 D) of age 6-12 years who were treated with 0.01% atropine or prescribed regular single vision spectacle and had follow-ups of more than 1 year were included.

Results

Data from 52 subjects were included. No difference was observed in the mean rate of change of spherical equivalent (SE) of more myopic eyes between 0.01% atropine (-0.56 D; 95% confidence interval [CI]: -0.82, -0.30) and single vision lens wearers (-0.59 D; 95% CI: -0.80, -0.37; P = 0.88). Similarly, insignificant change in the mean SE of less myopic eyes was noted between the groups (0.01% atropine group, -0.62 D; 95% CI: -0.88, -0.36 vs. single vision spectacle wearer group, -0.76 D; 95% CI: -1.00, -0.52; P = 0.43). None of the ocular biometric parameters showed any difference between the two groups. Though anisomyopic cohort treated with 0.01% atropine revealed a significant correlation between the rate of change of mean SE and axial length in both eyes (more myopic eyes, r = -0.58; P = 0.001 and less myopic eyes, r = -0.82; P < 0.001) compared to single vision spectacle wearer group, the change was not significant.

Conclusion

Administration of 0.01% atropine had minimal effect on reducing the rate of myopia progression in anisomyopic eyes.

IMI-Management and Investigation of High Myopia in Infants and Young Children

Purpose

The purpose of this study was to evaluate the epidemiology, etiology, clinical assessment, investigation, management, and visual consequences of high myopia (≤-6 diopters [D]) in infants and young children.

Findings

High myopia is rare in pre-school children with a prevalence less than 1%. The etiology of myopia in such children is different than in older children, with a high rate of secondary myopia associated with prematurity or genetic causes. The priority following the diagnosis of high myopia in childhood is to determine whether there is an associated medical diagnosis that may be of greater overall importance to the health of the child through a clinical evaluation that targets the commonest features associated with syndromic forms of myopia. Biometric evaluation (including axial length and corneal curvature) is important to distinguishing axial myopia from refractive myopia associated with abnormal development of the anterior segment. Additional investigation includes ocular imaging, electrophysiological tests, genetic testing, and involvement of pediatricians and clinical geneticists is often warranted. Following investigation, optical correction is essential, but this may be more challenging and complex than in older children. Application of myopia control interventions in this group of children requires a case-by-case approach due to the lack of evidence of efficacy and clinical heterogeneity of high myopia in young children.

Conclusions

High myopia in infants and young children is a rare condition with a different pattern of etiology to that seen in older children. The clinical management of such children, in terms of investigation, optical correction, and use of myopia control treatments, is a complex and often multidisciplinary process.

IMI-Onset and Progression of Myopia in Young Adults

Myopia typically starts and progresses during childhood, but onset and progression can occur during adulthood. The goals of this review are to summarize published data on myopia onset and progression in young adults, aged 18 to 40 years, to characterize myopia in this age group, to assess what is currently known, and to highlight the gaps in the current understanding. Specifically, the peer-reviewed literature was reviewed to: characterize the timeline and age of stabilization of juvenile-onset myopia; estimate the frequency of adult-onset myopia; evaluate the rate of myopia progression in adults, regardless of age of onset, both during the college years and later; describe the rate of axial elongation in myopic adults; identify risk factors for adult onset and progression; report myopia progression and axial elongation in adults who have undergone refractive surgery; and discuss myopia management and research study design. Adult-onset myopia is common, representing a third or more of all myopia in western populations, but less in East Asia, where onset during childhood is high. Clinically meaningful myopia progression continues in early adulthood and may average 1.00 diopters (D) between 20 and 30 years. Higher levels of myopia are associated with greater absolute risk of myopia-related ocular disease and visual impairment, and thus myopia in this age group requires ongoing management. Modalities established for myopia control in children would be options for adults, but it is difficult to predict their efficacy. The feasibility of studies of myopia control in adults is limited by the long duration required.

The Incidence and Severity of Myopia in the Population of Medical Students and Its Dependence on Various Demographic Factors and Vision Hygiene Habits

(1) Background: Myopia is one of the leading causes of visual impairment. Visual work and usage of electronic devices are known risk factors of myopia. Many education systems were forced to apply online and hybrid teaching methods, to reduce the number of new cases of COVID-19. Medical students are a population well-known for intense visual work in the form of learning; (2) Methods: Visual acuity and refractive error were measured in the population of medical students. Participants also filled out the survey that included their population characteristic and their habits related to the hygiene of vision; (3) Results: We found a correlation between the age of the first diagnosis of myopia and current values of refractive error. The majority of participants believe that the COVID-19 pandemic had an impact on the health of their vision. Among methods of studying, usage of the computer screen was less preferred by myopic students; (4) Conclusions: In the population of medical school students in Eastern Poland, visual acuity was lower than 1.0 in 232 (52.97%) in the right eye and 234 (53.42%) in the left eye. Early recognition of refractive error has influenced its current values. Among methods of studying, usage of the computer screen was less preferred by myopic students. More population-based studies should focus on the impact of the COVID-19 pandemic on the health of vision.

Progression of myopia among undergraduate students in central China

AIM

To investigate the progression of myopia and risk factors among university students in central China.

METHODS

A total of 7359 first-year undergraduate students at Huazhong University of Science and Technology in central China were recruited to the study and invited to a centralized clinic for medical examination, including optometry, and re-examined after one year. Correlation analyses were performed to assess the associations between one-year myopia progression and various parameters.

RESULTS

The spherical equivalent refraction for the overall population was -3.14±2.28 D at baseline. The rate of myopia progression over 0.50 D after one year was 41.9%, and the 1-year progression of myopia was -0.47±0.58 D. There was no difference of mean 1-year myopia progression between male and female or difference among age group. The myopia progression of original myopia was severer than progression of new-onset myopia. There was also difference of mean myopia progression among different degrees of myopia at baseline. The under corrected eyes had a higher percentage of myopia progression than well corrected eyes (χ ²=7.90, P<0.01). There was no correlation between myopia progression and height, weight, body mass index, hemoglobin (Spearman correlation, ρ=-0.078, -0.152, -0.170, -0.096, respectively, all P>0.05).

CONCLUSION

Myopes still progress in undergraduate students, especially in high myopes.

Myopic tilted disc: Mechanism, clinical significance, and public health implication

Myopic tilted disc is a common structural change of myopic eyes. With advancing ocular imaging technology, the associated structural changes of the eye, particularly the optic nerve head, have been extensively studied. These structural changes may increase patients' susceptibility to axonal damage and the risk of developing serious optic neuropathies including glaucoma. They also lead to diagnostic difficulties of disease suspects and treatment dilemmas of patients, which implicate clinical practice and subsequently the health care system. In the context of the mounting prevalence of myopia worldwide and its implications to irreversible visual impairment and blindness, it is essential to gain a thorough understanding of the structural changes of myopia. Myopic tilted disc has been extensively investigated by different study groups. However, generalizing the knowledge could be difficult because of the variable definitions of myopic tilted disc utilized in these studies and the complexities of the changes. The current review aimed to clarify the concepts and discuss various aspects of myopic tilted disc, including the definitions, association with other myopia-related changes, mechanism of tilted disc development, structural and functional changes, and clinical implications.

The biology of aging in a social world:insights from free-ranging rhesus macaques

Social adversity can increase the age-associated risk of disease and death, yet the biological mechanisms that link social adversities to aging remain poorly understood. Long-term naturalistic studies of nonhuman animals are crucial for integrating observations of social behavior throughout an individual's life with detailed anatomical, physiological, and molecular measurements. Here, we synthesize the body of research from one such naturalistic study system, Cayo Santiago Island, which is home to the world's longest continuously monitored free-ranging population of rhesus macaques. We review recent studies of age-related variation in morphology, gene regulation, microbiome composition, and immune function. We also discuss ecological and social modifiers of age-markers in this population. In particular, we summarize how a major natural disaster, Hurricane Maria, affected rhesus macaque physiology and social structure and highlight the context-dependent and domain-specific nature of aging modifiers. Finally, we conclude by providing directions for future study, on Cayo Santiago and elsewhere, that will further our understanding of aging across different domains and how social adversity modifies aging processes.

Cost-effectiveness analysis of myopia management: A systematic review

The rising prevalence of myopia is a major global public health concern. Economic evaluation of myopia interventions is critical for maximizing the benefits of treatment and the healthcare system. This systematic review aimed to evaluate the cost-effectiveness of interventions for treating myopia. Five databases were searched - Embase, Emcare, PubMed, Web of Science, and ProQuest - from inception to July 2022 and a total of 2,099 articles were identified. After careful assessments, 6 studies met the eligibility criteria. The primary outcomes of this systematic review were costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER). The secondary outcomes included utility values and net monetary benefits (NMB). One study determined the cost-effectiveness of photorefractive screening plus treatment with 0.01% atropine, 2 studies examined cost-effectiveness of corneal refractive surgery, and 3 studies evaluated cost-effectiveness of commonly used therapies for pathologic myopia. Corneal refractive surgeries included laser in situ keratomileusis (LASIK), femtosecond laser-assisted in situ keratomileusis (FS-LASIK), photorefractive keratectomy (PRK), and small-incision lenticule extraction (SMILE). Interventions for pathologic myopia included ranibizumab, conbercept, and photodynamic therapy (PDT). At an incremental cost of NZ$ 18 (95% CI 15, 20) (US$ 11) per person, photorefractive screening plus 0.01% atropine resulted in an ICER of NZ$ 1,590/QALY (US$ 1,001/QALY) (95% CI NZ$ 1,390, 1,791) for an incremental QALY of 0.0129 (95% CI 0.0127, 0.0131). The cost of refractive surgery in Europe ranged from €3,075 to €3,123 ([US$4,046 to $4,109 - adjusted to 2021 inflation). QALYs associated with these procedures were 23 (FS-LASIK) and 24 (SMILE and PRK) with utility values of 0.8 and ICERs ranging from approximately €14 (US$17)/QALY to €19 (US$23)/QALY. The ICER of LASIK was US$683/diopter gained (inflation-adjusted). The ICER of ranibizumab and PDT were £8,778 (US$12,032)/QALY and US$322,460/QALY respectively, with conbercept yielding a saving of 541,974 RMB (US$80,163)/QALY, respectively. The use of 0.01% atropine and corneal refractive surgery were cost-effective for treating myopia. Treating pathologic myopia with ranibizumab and conbercept were more cost-effective than PDT. Prevention of myopia progression is more cost-effective than treating pathologic myopia.

Myopia: An ounce of prevention is worth a pound of cure

PURPOSE

Myopia severity has a profound impact on visual impairment in later life. A patient's final level of myopia may be lowered by myopia control, but also by delaying onset. Here, we evaluate the influence of the age of onset on the final recorded level of myopia.

METHODS

Data were extracted from: (1) Three prospective cohort studies of myopia progression in East Asia and the United States where the final recorded level of myopia is presented as a function of the established age of onset. (2) Four retrospective studies of myopia progression in Finland, India, the Netherlands and China and two cross-sectional studies in Argentina and the UK where the age of onset was based on self-report of age at first spectacle prescription. (3) A cohort study of Finnish subjects originally recruited for a clinical trial and followed into adulthood. Subjects were divided into five groups according to age at recruitment that was used as a surrogate for the age of onset.

RESULTS

Final recorded level of myopia was plotted as a function of age of onset for all studies. Among the three East Asian studies, the slopes are between 0.68 and 0.97 D/year, meaning that each later year of onset is associated with between 0.68 and 0.97 less myopia at the final recorded refraction. For six of the seven non-East Asian studies, the slopes are substantially flatter, with slopes between 0.23 and 0.50 D/year. By contrast, the slope for the Finnish study was 0.87 D/year. Increasing age of final recorded refraction tended to be associated with higher levels of myopia.

CONCLUSION

Among East Asians, delaying the onset of myopia by 1 year has the potential to lower the final myopia level by 0.75 D or more-equivalent to 2-3 years of myopia control with existing modalities. The benefit is lower, but meaningful, among non-East Asians.

Effect of the combined application of orthokeratology and single-vision spectacles on slowing the progression of high myopia: A systematic review and meta-analysis

PURPOSE

The purpose of the study was to conduct a meta-analysis about the effect of the combined application of orthokeratology and single-vision spectacles on slowing the progression of high myopia.

METHODS

The literature was searched in PubMed, EMBASE, the Cochrane Library, Wang Fang Data, CNKI and sinoMed. The Cochrane Handbook was used to evaluate the quality of the included randomized clinical trials, and the Newcastle-Ottawa Scale was used to evaluate the included case-control or cohort studies. The results were analyzed by Revman 5.3.

RESULTS

Five studies (2 randomized clinical trials, 2 case-controls, and 1 cohort study) with a total of 360 patients were included in this meta-analysis. The follow-up time was at least 1 year. Combined application of orthokeratology and single-vision spectacles were used in the experimental group. The control group used single-vision spectacles only. The pooled estimates indicated that the standardized mean difference between the 2 groups was -1.46 mm (95% confidence interval: -1.88 to -1.05; P < .05) for axial length elongation and -1.85D (95% confidence interval: -2.40 to -1.31; P < .05) for change in spherical equivalent refraction. No serious adverse events were reported in all studies.

CONCLUSION

The combined application of orthokeratology and single-vision spectacles is more effective than single-vision spectacles only on slowing the progression of high myopia.

Myopia progression and stabilization in school-aged children with single-vision lenses

PURPOSE

To investigate the longitudinal changes in myopia from onset to stabilization in school-aged children with single-vison lenses (SVLs).

METHODS

The medical records of patients wearing SVLs with long-term follow-up data between 2006 and 2016 were retrospectively reviewed. The patients who were 6-10 years old at the initial visit and 16 years old at the last assessment were included and analysed. The periods of progression and stabilization of myopia were evaluated by plotting fitted curves of the changes in spherical equivalent (SE).

RESULTS

Seven hundred and seventy-three patients (median initial age 9 years) were accessed over an average of 7 years (IQR, 6-7 years). The initial mean SE was -1.92 ± 1.57 D and increased to -6.05 ± 2.14 D at 16 years old. The average age at myopia stabilization was 14.6 years, and girls slightly stabilized earlier than boys. 73.7% of the 6-year-olds and 85.7% of the 7-year-olds had high myopia at 16 years old, and the risk decreased each year from 7 to 10 years old. Children who had SE greater than -4 D up to 10 years had 89.0% risk of high myopia at 16 years old. Children with SE between -0.5 D and -2 D still had 34% risk of developing high myopia at 16 years old.

CONCLUSION

This study provides a comprehensive picture of myopia progression from onset to stabilization in school-aged children with SVLs in China. All children who have myopia onset below 10 years of age were at risk for high myopia, and children who have myopia onset below 8 years of age require more attention.

Refractive development in individuals with ocular and oculocutaneous albinism

PURPOSE

Albinism is known to disrupt emmetropisation in animal models. However, it is not clear if the same effect is seen in humans. This study aimed to investigate the refractive profile in individuals diagnosed with ocular albinism (OA) and oculocutaneous albinism (OCA) based on a large dataset.

METHODS

Required data from 618 individuals (61% males and 39% females) diagnosed with albinism were exported from the eyeSmart electronic medical records of L V Prasad Eye Institute. Overall, there were 112 (18%) individuals diagnosed with OA and 506 (82%) with OCA. Based on the spherical equivalent refraction (SER), individuals were classified as emmetropes, myopes, and hyperopes.

RESULTS

The overall spherical equivalent refraction of the individuals ranged from -25.00D to + 12.00D with a median + 0.25D (-2.00 to + 2.25 D). The proportion of individuals with albinism (combined OA, OCA) having hyperopia and myopia (overall: N = 282;45.6% vs. N = 245;39.6%) were similar (p = 0.18), and the least were with emmetropia (overall: N = 91;14.7%). Across all the age groups (0-10, 11-20, 21-30, > 30 years), the frequency of hyperopes and myopes was significantly higher (p < 0.05) compared to emmetropes. Both high degrees of hyperopia and myopia were found in individuals diagnosed with OA and OCA. Irrespective of the albinism type, with-the-rule (70%) astigmatism was the most prevalent compared to other types of astigmatism. The frequency of with-the-rule astigmatism was significantly high in the presence of nystagmus compared to individuals with no nystagmus in both OA (75% vs 25%, p = 0.01) and OCA (77% vs 23%, p = 0.014) groups.

CONCLUSION

The presence of both high hyperopia and high myopia and very few numbers with emmetropia across all age groups indicates disrupted normal refractive development in individuals with albinism. With-the-rule astigmatism and nystagmus may result in meridional degradation of the retinal image leading to impairment of normal emmetropisation process in individuals with albinism.

Comparing the natural progression and clinical features of keratoconus between pediatric and adult patients

To present the natural course of keratoconus (KC) and compare pediatric and adult patients. Design A retrospective cohort study. Setting Hospital-based. Patient Population In total, 152 patients (288 eyes) diagnosed with KC at Chang Gung Memorial Hospital, Taiwan, were included. Previously managed patients and those with missing optical data were excluded. Observation Procedures Patients were divided into pediatric (≤ 18 years) and adult (> 18 years) groups. Demographics, clinical data, and optical variables were collected, including corrected distance visual acuity (CDVA), refractive error, and keratometric readings (K). Main Outcome Measure Optical variables at the final follow-up before aggressive treatment. Results In total, 20 pediatric (37 eyes) and 132 adults (251 eyes) patients were eligible for this study. The mean follow-up time was 2.98 years. Male predominance was observed in both groups. Both groups had similar clinical characteristics and optical variables at the initial diagnosis. Pediatric patients progressed significantly more rapidly in refractive errors, including spheres and cylinders, spherical equivalence, steep K, and flat K during the follow-up. However, significant change between the two study groups was only seen in sphere refractive error spherical equivalence. Conclusion Pediatric patients had more rapidly progressive KC than adult patients, so early detection and frequent follow-up for prompt interventions are necessary for these patients.

Genetic susceptibility to high myopia in Han Chinese population

High myopia is a common ocular genetic disease in the world. The study sought to investigate the effect of the Insulin-like growth factor-1 (IGF-1) and Matrix metalloproteinase-9 (MMP-9) genes polymorphisms on high myopia in a Han population of China. This study recruited 216 unrelated Han Chinese subjects, including 103 cases with high myopia and 113 controls. Four tagging single nucleotide polymorphisms (SNPs) of IGF-1 and MMP-9 genes were genotyped using the Sequenom MassARRAY method. The chi-square test showed that the family history was significantly correlated with myopia. The SNP genotypes were all in Hardy–Weinberg equilibrium (P > 0.05). Among the four SNPs, there were statistically significant differences in the genotype and allele frequencies of rs2236416 between the groups (P = 0.024). The significant associations of rs2236416 between cases and controls also appeared after Bonferroni multiple correction (P = 0.024). Then, there were significant differences in the genotypes dominant model and codominant model of rs2236416 between groups (P = 0.007 and P = 0.004, respectively). rs5742632 showed a significant difference between the cases and the controls in the recessive model (P = 0.037). Our findings indicated that rs2236416 of MMP-9 was associated with myopia in the population. The result suggested MMP-9 gene locus may play a role in myopia.

Development pattern of ocular biometric parameters and refractive error in young Chinese adults: a longitudinal study of first-year university students

Background

The increase in the prevalence of myopia has become a matter of serious public health concern, and few studies to date have examined the ocular biometric parameters of myopia in young Chinese adults. This study aimed to investigate the longitudinal ocular biometric and refractive development of first-year university students and the influence of near work.

Methods

This study included 526 first-year university students from Tianjin Medical University (mean age, 18.34 years; 313 females and 213 males). From 2016 to 2018, participants underwent ocular biometry measurements and subjective refraction annually. Near-work activities such as the use of electronic devices, online games, reading, and writing as well as demographic data were recorded by questionnaires.

Results

The prevalence of myopia in this population from 2016 to 2018 was 92.40%, 92.59%, and 92.97%, respectively. Importantly, the prevalence of high myopia increased significantly from 20.91% to 28.33% (P < .001). The spherical equivalent refraction was significantly more myopic by approximately − 0.38 D (from − 4.18 ± 2.44 to − 4.56 ± 2.57 D; P < .001) during the period. The axial length, central corneal thickness, and lens thickness became significantly different (all P < .05), and the axial length significantly increased by 0.12 mm during 2 years (P < .001). Using binary logistic regression analysis, the data indicated that spending more time on online games (odds ratio, 2.09; 95% confidence interval, 1.33–3.29) could speed up the progression of myopia (P < .05).

Conclusions

This study showed that the prevalence of high myopia continued to increase in undergraduate students over 2 years. Baseline myopia correlated with myopic shift, the time spent on online games, and parental myopia were significantly associated with an increase in myopia in these young adult populations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-022-02440-9.

Retinal and Choroidal Thickness in Myopic Young Adults

The retinal and the choroidal thickness were measured at four locations along the horizontal direction (foveola, one nasal to the fovea and two temporal) in a group of 43 young adults (mean age: 27.1 ± 3.9 years), with ocular refraction ranging from emmetropia to high myopia (0 to −10D). Thickness values were obtained from OCT images centered at the foveal depression. The retinal thickness exhibited a correlation with refraction at all eccentricities but not at the fovea. When different subgroups of refraction were considered, the analysis of such correlations indicated that only the retinal thickness in the group of high myopia (refraction ≤ −6D) was statistically different from the other two groups (emmetropes: [−0.5, 0] D, and myopes: (−6, −0.5) D). No significant differences were found between emmetropic and myopic groups. In contrast to the retina, the choroidal thickness exhibited a significant correlation with refraction at the fovea, although such dependency only stood for high myopes (the choroid of myopes and emmetropes exhibited similar thickness). Correlation with refraction was also found at the nasal location, arising between emmetropic and high myopia groups. Other choroidal locations among groups did not exhibit relationship with the refraction. It is concluded that the differences in the choroid and retina thickness along the horizontal meridian as a function of refraction do not characterize the onset and progression of myopia at early stages, since they only manifest in the group of high myopia.

Next-Generation Sequencing Screening of 43 Families with Non-Syndromic Early-Onset High Myopia: A Clinical and Genetic Study

Early-onset high myopia (EoHM) is a disease that causes a spherical refraction error of ≥-6 diopters before 10 years of age, with potential multiple ocular complications. In this article, we report a clinical and genetic study of 43 families with EoHM recruited in our center. A complete ophthalmological evaluation was performed, and a sample of peripheral blood was obtained from proband and family members. DNA was analyzed using a customized next-generation sequencing panel that included 419 genes related to ophthalmological disorders with a suspected genetic cause, and genes related to EoHM pathogenesis. We detected pathogenic and likely pathogenic variants in 23.9% of the families and detected variants of unknown significance in 76.1%. Of these, 5.7% were found in genes related to non-syndromic EoHM, 48.6% in genes associated with inherited retinal dystrophies that can include a syndromic phenotype, and 45.7% in genes that are not directly related to EoHM or retinal dystrophy. We found no candidate genes in 23% of the patients, which suggests that further studies are needed. We propose a systematic genetic analysis for patients with EoHM because it helps with follow-up, prognosis and genetic counseling.

Comparison of Two Main Orthokeratology Lens Designs in Efficacy and Safety for Myopia Control

Purpose

This study aimed to compare the efficacy and safety of corneal refractive therapy (CRT) lenses and vision shaping treatment (VST) lenses for myopia control in children.

Methods

Medical records of 1,001 children (2,002 eyes) who had been fitted with orthokeratology lenses for over 1.5 years were retrospectively reviewed. We collected the clinical data of four types of orthokeratology (OK) lenses available: one CRT lens (brand: CRT) and three VST lenses (brands: Euclid, Alpha, and Hiline) over 1.5 years. Results were compared and analyzed using a one-way ANOVA and Pearson's chi-square test.

Results

Axial length elongation in the CRT lens group was 0.13 ± 0.02 mm faster than that in the Euclid lens, 0.1 ± 0.02 mm faster in the Alpha lens, and 0.08 ± 0.02 mm faster in the Hiline lens over the 1.5-year period (all P < 0.05). Among the subjects, 37.3% of them using the CRT lens experienced more than 1 D of refractive growth, compared with 20.2–30.8% of subjects wearing the three groups of VST lenses (all P < 0.05). A lower incidence of total adverse events was found with the CRT lenses compared with the VST lenses (P < 0.05), especially corneal staining. No difference was found in axial length elongation, refraction growth, and incidence of adverse events among the three types of VST lenses (all P > 0.05).

Conclusions

Compared with the VST lenses, CRT lenses demonstrated a weaker effect on myopia control but with a better safety profile. Different types of VST lenses had similar efficacy and safety in the context of controlling myopia progression.

Coronavirus disease 2019 outbreak and associated public health measures increase the progression of myopia among children and adolescents: Evidence synthesis

Purpose

Although studies have suggested that the coronavirus disease 2019 (COVID‐19) outbreak increased myopia progression, they had different settings and analysis methods. This study compared myopia progression before and during the COVID‐19 outbreak using meta‐analysis.

Methods

Relevant literature was searched on EMBASE, PubMed, ClinEpiDB and Web of Science and reviewed until 8 October 2021. The Newcastle–Ottawa Scale was used to evaluate the quality of the original studies. The mean difference of change in spherical equivalent refraction (SER) was used for evaluation before and during the COVID‐19 pandemic.

Results

The meta‐analysis included eight studies with 773, 797 individuals aged 5–18 years. Pooled analysis indicated that the mean difference of annual myopia progression during the pandemic was 0.41 D higher (95% confidence interval [CI]: 0.35–0.48, p < 0.01) than before the pandemic. Subgroup analysis using cycloplegic (mean difference, 0.30 D; 95% CI, 0.22–0.38; p < 0.01) or noncycloplegic refraction (mean difference, 0.60 D; 95% CI, 0.27–0.93; p < 0.01) indicated that the mean difference of annual myopia progression during COVID‐19 significantly increased in both refractive measurements.

Conclusion

Our findings demonstrated that the COVID‐19 pandemic accelerated myopic progression compared to the past. Government policies are urgently required to prevent and control myopia progression.

Longitudinal analysis of 5-year refractive changes in a large Japanese population

Refractive changes are reportedly affected by age, sex, and current refractive error. To clarify the pattern of refractive changes in a Japanese population, we conducted a 5-year follow-up longitudinal analysis of spherical equivalent (SE) refractive changes with stratification by sex, age, and SE in 593,273 eyes from Japanese individuals ages 3–91 years. The 5-year SE change with myopic shift dramatically increased over time after age 4 years, and the largest change was observed in both males and females who were age 8 years at baseline [males: − 2.654 ± 0.048 diopters (D); females: − 3.110 ± 0.038 D]. During school age, the 5-year myopic change was greater in females than in males, and emmetropic and low-to-moderate myopic eyes underwent larger myopic changes than hyperopic and high-to-severe myopic eyes. After the peak at age 8 years, the 5-year myopic change gradually declined with age and fell below − 0.25 D at age 27 in males and age 26 years in females. The 5-year SE changes transitioned from a myopic to a hyperopic shift at age 51 in both sexes, and hyperopization advanced more quickly in hyperopic eyes. Our findings highlight the importance of myopia prevention in school-aged children.

Efficacy of long-term orthokeratology treatment in children with anisometropic myopia

AIM

To explore the efficacy of the orthokeratology lens for anisometropic myopia progression.

METHODS

A retrospective study was performed. Cycloplegic refraction and axial length (AL) were collected from 50 children (10.52±1.72y) who visited Peking University Third Hospital from July 2015 to August 2020. These children's one eyes (Group A) received monocular orthokeratology lenses at first, after different durations (12.20±6.94mo), their contralateral eyes (Group B) developed myopia and receive orthokeratology as well. The data in 1-year of binocular period were recorded. AL growth rate (difference of follow-up and baseline per month) were compared between two groups by paired t test. Interocular differences of AL were compared by Wilcoxon test.

RESULTS

During monocular period, the AL growth rate of the Group A (0.008±0.022 mm/mo) was significantly slower than that of the Group B (0.038±0.018 mm/mo; P<0.0001). However, during binocular period, the AL growth rate of the Group A (0.026±0.014 mm/mo) was significantly faster than that of the Group B (0.016±0.015 mm/mo; P<0.0001). The AL difference between both eyes was 0.6 (0.46) mm, then significantly decreased to 0.22 (0.39) mm when started binocular treatment (P<0.0001). However, it was significantly increased to 0.30 (0.32) mm after a year (P<0.0001), but still significantly lower than baseline (P<0.0001).

CONCLUSION

The orthokeratology lens is efficient for control the AL elongation of monocular myopia eyes and reduce anisometropia. For the condition that the contralateral eyes develop myopia and receive orthokeratology lens later, there is no efficiency observed on control interocular difference of AL during binocular treatment.