Myopia Growth Chart Based on a Population-Based Survey (KNHANES IV-V): A Novel Prediction Model of Myopic Progression in Childhood

Verification of a nationwide population-based myopia growth chart in a large longitudinal cohort of 1155 Korean children

OBJECTIVE

To evaluate predictive value of the myopia growth chart based on population-based health survey data using longitudinal cohorts.

METHODS

Patients aged from 5 to 18 years and underwent two or more cycloplegic refraction (CR) exams with at least one year of interval were included. Percentile deviation was calculated by subtracting percentile at final exam from the percentile at initial exam based on the chart. Spherical equivalent (SE) deviation was calculated by SE at final CR subtracted from predicted SE based on initial CR using the chart.

RESULTS

2310 eyes from 1155 subjects were included. There were 1344 eyes (58.2%) categorized as inliers, where both initial and final CR were within the 2nd to 99th percentile. Mean percentile and SE deviations were + 11.0 ± 22.9 percentiles and -0.60 ± 1.33 diopters, each. Outliers, those except the inliers, were 966 eyes (41.8%). Most outliers (709 eyes, 73.4%) were outside the chart for both initial and final exam. The rest of the outliers (257 eyes, 26.2%) were within the 2 to 99 percentile range on the chart at least once, either at initial or final exams; most of those (202 eyes, 78.6%) progressed toward myopia more than predicted.

CONCLUSIONS

In our large cohorts, both inliers and outliers tended to progress toward more myopia than predicted from the chart. This suggests the chart predicts childhood myopia rather conservatively. The myopia growth chart may be useful as a screening tool in detecting children at high risk of developing high myopia.

Juvenile-onset myopia-who to treat and how to evaluate success

The risk of eye diseases such as myopic macular degeneration increases with the level of myopia, but there is no safe level of myopia and the burden of lower degrees of myopia remains considerable. Effective treatments are available that slow progression and thus limit the final degree of myopia. In this review, the rationale for slowing progression is summarized, and a case made for treating all myopic children. Measurement of refractive error and axial length is reviewed, stressing the precision of optical biometry, but also the need for cycloplegic autorefraction. The factors influencing progression are considered and the available tools for interpretation of progression rate are discussed. Finally, the need to set attainable treatment goals is emphasized.

Longitudinal analysis of refraction and ocular biometrics in preschool children with early-onset high myopia

We investigated changes in refraction and ocular biometrics in preschool children with early-onset high myopia. Sixty eyes of 60 children with a mean follow-up time of 58.5 months were included in this study. At baseline, mean age of children was 55.6 ± 13.1 months, mean spherical equivalent (SE) was - 8.59 ± 2.66 D, and 25.64 ± 1.16 mm for axial length (AL). The total annual rate of myopic progression and axial elongation were - 0.37 ± 0.39 D/year and 0.33 ± 0.18 mm/year, respectively. During follow-up period, there was a trend toward less myopic progression and axial elongation over time. Of the total participants, 24 children (40%) were in the myopia progression group and the remaining 36 children (60%) were in the myopia stability group. In multiple linear regression analysis, baseline SE and AL were independently associated with myopic progression, while age, sex, and baseline AL-to-CR ratio were not related to myopic progression. According to the model, more myopic SE (β = - 0.186, P = 0.035) and longer AL (β = - 0.391, P = 0.008) at baseline were significantly associated with myopic progression. Myopia progression in preschoolers with high myopia tended to be relatively modest, with 60% of subjects exhibited myopic stability. Higher myopic SE, and longer AL at baseline were associated with myopic progression in preschool children with high myopia.

Percentile curves of refractive errors in a Spanish paediatric population

OBJECTIVE

The main objective of this study was to obtain percentile curves of refractive errors in a Spanish paediatric population aged between 3 and 12 years.

MATERIALS AND METHOD

A descriptive, observational and cross-sectional study was conducted, including children aged between 3 and 12 years who did not present with any known ocular and/or systemic diseases. The convenience sampling method was used to select the sample from three schools and one hospital in the Community of Madrid. The refractive error was obtained using a Retinomax K-plus 3 autorefractometer (RTX; Right Mfg. Co. Ltd., Tokyo, Japan). The 5th, 10th, 25th, 50th, 75th, 90th and 95th percentiles were calculated using the IBM SPSS Statistics v.24 statistical software (IBM Corporation, Armonk, NY, United States).

RESULTS

A total of 688 children with a mean age of 7.68 ± 2.17 years were analysed. In the 50th percentile curve, spherical equivalent values started to become myopic at 3 years (SE < -0.50 D) and the 75th percentile curve also turned myopic at 4 years. As a result, it was observed that the spherical equivalent value became more negative with time, starting from the ages indicated above. Therefore, the 90th percentile curve was negative at 11 years.

CONCLUSION

Percentile curves of refractive errors in a Spanish paediatric population have been presented for the first time in order to help eyecare professionals detect children with refractive errors at an early age.

Myopia prediction: a systematic review

Myopia is a leading cause of visual impairment and has raised significant international concern in recent decades with rapidly increasing prevalence and incidence worldwide. Accurate prediction of future myopia risk could help identify high-risk children for early targeted intervention to delay myopia onset or slow myopia progression. Researchers have built and assessed various myopia prediction models based on different datasets, including baseline refraction or biometric data, lifestyle data, genetic data, and data integration. Here, we summarize all related work published in the past 30 years and provide a comprehensive review of myopia prediction methods, datasets, and performance, which could serve as a useful reference and valuable guideline for future research.

Ocular biometric features of pediatric patients with fibroblast growth factor receptor-related syndromic craniosynostosis

Ametropia is reported as a common ophthalmic manifestation in craniosynostosis. We retrospectively compared childhood refractive error and ocular biometric features of fibroblast growth factor receptor (FGFR)-related syndromic craniosynostosis patients with those of non-syndromic craniosynostosis and control subjects. Thirty-six eyes (18 patients) with FGFR-related syndromic craniosynostosis, 76 eyes (38 patients) with non-syndromic craniosynostosis, and 114 eyes (57 patients) of intermittent exotropes were included in the analysis. Mean age at examination was 7.82 ± 2.51 (range, 4–16) years and mean spherical equivalent was -0.09 ± 1.46 Diopter. Mean age and refractive error were not different between groups, but syndromic craniosynostosis patients had significantly longer axial length, lower corneal power, and lower lens power than other groups (p < 0.01, p < 0.01, and p < 0.01, respectively). Axial length was positively correlated and keratometry and lens power were negatively correlated with age in non-syndromic craniosynostosis and controls, while these correlations between age and ocular biometric parameters were not present in the FGFR-related syndromic craniosynostosis. In conclusion, ocular biometric parameters in FGFR-related syndromic craniosynostosis differed from those of non-syndromic craniosynostosis and age-matched controls, and did not show the relations with age, suggesting this cohort may have abnormal refractive growth.

Axial growth and refractive change in white European children and young adults: predictive factors for myopia

This report describes development of spherical equivalent refraction (SER) and axial length (AL) in two population-based cohorts of white, European children. Predictive factors for myopic growth were explored. Participants were aged 6-7- (n = 390) and 12-13-years (n = 657) at baseline. SER and AL were assessed at baseline and 3, 6 and 9 years prospectively. Between 6 and 16 years: latent growth mixture modelling identified four SER classes (Persistent Emmetropes-PEMM, Persistent Moderate Hyperopes-PMHYP, Persistent High Hyperopes-PHHYP and Emerging Myopes-EMYO) as optimal to characterise refractive progression and two classes to characterise AL. Between 12 and 22-years: five SER classes (PHHYP, PMHYP, PEMM, Low Progressing Myopes-LPMYO and High Progressing Myopes-HPMYO) and four AL classes were identified. EMYO had significantly longer baseline AL (≥ 23.19 mm) (OR 2.5, CI 1.05-5.97) and at least one myopic parent (OR 6.28, CI 1.01-38.93). More myopic SER at 6-7 years (≤ + 0.19D) signalled risk for earlier myopia onset by 10-years in comparison to baseline SER of those who became myopic by 13 or 16 years (p ≤ 0.02). SER and AL progressed more slowly in myopes aged 12-22-years (- 0.16D, 0.15 mm) compared to 6-16-years (- 0.41D, 0.30 mm). These growth trajectories and risk criteria allow prediction of abnormal myopigenic growth and constitute an important resource for developing and testing anti-myopia interventions.

Reference curves for refraction in a German cohort of healthy children and adolescents

PURPOSE

Percentile curves of refractive development for German children were generated. We hypothesize that refraction in children in central Europe might differ from data in central Asia.

METHODS

Non-cycloplegic refraction was measured using the ZEISS i.Profiler plus (Carl Zeiss Vision GmbH, Germany) in 1999 children, of which were 1046 male and 953 female, aged 3 to 18 years. Reference curves were calculated with the R-package GAMLSS as continuous function of age.

RESULTS

There were only little differences for all centiles between the genders at 3 years and a general trend towards more myopia with increasing age. For the 97th centile and the 3rd centile, girls showed higher myopia/ less hyperopia than boys. Between the age of 3 and 18, the median refraction became -0.68 D and -0.74 D more myopic for boys and girls, respectively. At the same time, the 97th centile for boys changed +0.29 D towards hyperopia and in girls -0.52 D towards myopia. A general myopic trend was seen in the 3rd centile, which was -2.46 D for boys and -2.98 D for girls. For both genders, the median became less than zero at the age of 10 years but did not become myopic (less than -0.5 D) up to the age of 18.

CONCLUSION

Our analysis presents the first reference curve for refraction in central Europe. In comparison to data from China and Korea, there is only little difference at the age of 5 years in all centiles which then increases continuously. For all ethnicities, a trend towards myopia with increasing age could be observed, but myopia progression is much higher in China and Korea than in Germany. The most marked differences can be seen in the lower centiles. Further investigations should clarify whether commencement of preschool activities with prolonged near-work initiates the divergence in refractive development.

Association between myopia and peripapillary hyperreflective ovoid mass-like structures in children

We investigated the characteristics of children with peripapillary hyperreflective ovoid mass-like structures (PHOMS) and evaluated the associated risk factors. This cross-sectional study included 132 eyes of 66 children with PHOMS and 92 eyes of 46 children without PHOMS (controls) who were assessed by disc enhanced-depth image spectral-domain (SD) optical coherence tomography (OCT). Univariable and multivariable logistic analyses were performed to evaluate risk factors associated with presence of PHOMS. Among the 66 children with PHOMS, 53 (80.3%) had bilateral and 13 (19.7%) had unilateral PHOMS. The mean age of the PHOMS group was 11.7 ± 2.6 years, and that of the control group was 11.4 ± 3.1 years. The mean spherical equivalent (SE) as determined by cycloplegic refraction was −3.13 ± 1.87 diopters (D) in the PHOMS group and −0.95 ± 2.65 D in the control group. Additionally, mean astigmatism was 0.67 ± 0.89 D and 0.88 ± 1.02 D in the PHOMS group and the control group, respectively. Mean disc size was 1,735 ± 153 µm in the PHOMS group and 1,741 ± 190 µm in the control group, while mean optic nerve head (ONH) tilt angle was 9.84 ± 5.38 degrees in the PHOMS group and 3.71 ± 4.41 degrees in the control group. SE and ONH tilt angle were significantly associated with PHOMS according to both univariable [odds ratio (OR): 1.59; p < 0.001 and OR: 1.35; p < 0.001, respectively] and multivariable (OR: 1.71; p = 0.001 and OR: 1.29; p = 0.001, respectively) logistic regression analyses. There was a significant correlation between SE and ONH tilt (r = −0.46; p < 0.001). In conclusion, PHOMS is associated with myopic shift in children, and optic disc tilt may be a mediator between myopia and PHOMS.

Factors associated with myopia in Korean children: Korea National Health and nutrition examination survey 2016-2017 (KNHANES VII)

BACKGROUND

To evaluate the prevalence and risk factors associated with myopia and high myopia in children in South Korea.

METHODS

A total of 983 children 5-18 years of age who participated in the Korean National Health and Nutrition Examination Survey 2016-2017 (KNHANES VII), a nationwide population-based cross-sectional study, were evaluated. Myopia and high myopia were defined as a spherical equivalent (SE) ≤ - 0.5 diopters (D) and SE ≤ --6.0 D. The association between refractive errors and potential risk factors for myopia was analyzed.

RESULTS

The prevalence of myopia and high myopia was 65.4 and 6.9%, respectively. Older age and parental myopia were significantly associated with both myopia and high myopia, while higher body mass index (BMI) was associated with high myopia only. Although the proportion of subjects who spent more time on near work activities (≥4 h/day) was sequentially increased with increased refractive error, this tendency was not statistically significant by multivariable logistic regression.

CONCLUSIONS

Korean children had a high prevalence of myopia and high myopia. In this age group, the risk of myopia increased with aging and parental myopia. Higher BMI may be associated with high myopia.

Refractive, biometric and corneal topographic parameter changes during 12 months of orthokeratology

BACKGROUND

The aim of this study was to monitor refractive, topographic and biometric changes in Singaporean myopic children fitted with orthokeratology over a period of 12 months.

METHODS

Data from 62 myopic eyes from an Asian population corrected with orthokeratology were retrospectively collected from an optometric clinic in Singapore. Anterior segment parameters were analysed with a Pentacam. Axial length was measured using the IOLMaster and refraction was assessed by subjective examination before the treatment and after one night, one week, and one, three, six and 12 months. A logistic regression model was built to evaluate the probability of slower (< 0.10 mm/year) or faster eye growth (≥ 0.10 mm/year).

RESULTS

Subjects had a mean age of 12.2 ± 3.9 years (range 5-19 years), and 71 per cent were female. Baseline myopia was -3.95 ± 1.59 D (range -1.50 and -8.75 D). Statistically significant differences were found after 12 months of treatment for refractive error, parameters of the central anterior corneal surface (curvature and elevation) and central corneal thickness. Topographic and thickness changes stabilised after one week of treatment. During 12 months of orthokeratology treatment there was a significant increase of axial length (difference = 0.11 ± 0.18 mm, p < 0.001) while refraction remained stable. Changes in axial length of subjects above 11 years were not statistically significantly independent of the baseline myopia, and in subjects with baseline myopia greater than 4.00 D. Logistic regression showed that each additional year of age and each additional dioptre of baseline myopia decreased the probability of faster axial elongation (odds ratio [OR] = 1.23, 2.19 95% CI; OR = 1.08, 3.47 95% CI, respectively).

CONCLUSION

Corneal parameters in orthokeratology treatment were stable after one week, particularly for myopes under 4.00 D. Axial length did not change significantly in children older than 11 years of age or in subjects with myopia above 4.00 D undergoing orthokeratology treatment.