Link between parental myopia and early-onset high myopia: Insights from a clinical retrospective analysis.

INTRODUCTION: Genetic aetiology is suspected in the development of early-onset high myopia (spherical equivalent refractive error [SER] ≤-6.00 D at ≤6 years of age), considering that the role of environmental factors in inducing high myopia is improbable at an early age. Therefore, we aimed to understand if early-onset high myopia is associated with parental myopia in a clinical setting. METHODS: A retrospective study was conducted in which information about demographics, age of apparent onset of myopia, refractive error, axial length, number of myopic parents, time spent outdoors and time spent on near-work was obtained from electronic medical records (EMR). It included 195 myopic individuals categorised into (1) Early-onset high myopes (EOHM): SER ≤ -6.00 D with age of presentation ≤6 years, (2) Early-onset low myopes (EOLM): SER > -6.00 D with age of apparent onset ≤6 years, (3) Late-onset high myopes (LOHM): SER ≤ -6.00 D with age of presentation and age of apparent onset >6 years and (4) Late-onset low myopes (LOLM): SER > -6.00 D with age of apparent onset >6 years. RESULTS: Overall, 63% of individuals were found to have parental myopia. The proportion of individuals with EOHM, EOLM, LOHM and LOLM with parental myopia was 57%, 74%, 53% and 64%, respectively. After adjustment for age, gender and environmental factors, the odds of development of EOHM (Odds ratio: 0.78, 95% confidence interval: 0.25-2.48), EOLM (1.54, 0.65-3.67) or LOHM (0.70, 0.30-1.65) were similar in the presence of myopic parents, when compared with LOLM. The SER and axial length did not differ based on the number of myopic parents in any of these categories. CONCLUSION: This retrospective analysis reveals that the presence of parental myopia, which was self-reported, did not induce additional risk for early-onset high myopia.

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.

Peripheral Refraction Using Ancillary Retinoscope Component (P-ARC).

Purpose: To assess the agreement of retinoscope-based peripheral refraction techniques with the criterion standard open-field autorefractor. Methods: Fifty young adults (mean age, 24 ± 3 years) participated in this study. Two masked, experienced senior examiners carried out central refraction and peripheral refraction at the temporal 22° (T22°) and nasal 22° (N22°) eccentricities. Peripheral refraction techniques were (a) peripheral refraction using ancillary retinoscope component (P-ARC), (b) retinoscopy with eye rotation, and (c) open-field autorefractor. Peripheral refraction with retinoscopy values was compared with an open-field autorefractor (Shinn Nippon NVision-K) to assess the agreement. All measurements were taken from the right eye under noncycloplegic conditions. Results: The mean difference ±95% limits of agreement of peripheral refraction values obtained using P-ARC from T22° (+0.11 diopters [D] ± 1.20 D; P = 0.20) or N22° (+0.13 D ± 1.16 D; P = 0.13) were comparable with open-field autorefractor. The eye rotation technique compared to autorefractor showed a significant difference for T22° (+0.30 D ± 1.26 D; P = 0.002); however, there was an agreement for N22° (+0.14 D ± 1.16 D; P = 0.10). With respect to the identification of peripheral refraction patterns, examiners were able to identify relative peripheral hyperopia in most of the participants (77%). Conclusions: Peripheral refraction with P-ARC was comparable with open-field autorefractor at T22° and N22° eccentricities. Peripheral retinoscopy techniques can be another approache for estimating and identifying peripheral refraction and its patterns in a regular clinical setting. Translational Relevance: Retinoscope with P-ARC has high potential to guide and enable eye care practitioners to perform peripheral refraction and identify peripheral refraction patterns for effective myopia management.

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.

Biometry-Based Technique for Determining the Anterior Scleral Thickness: Validation Using Optical Coherence Tomography Landmarks.

Purpose: Considering the potential role of anterior scleral thickness (AST) in myopia and the ubiquitous use of optical biometers, we applied and validated a biometry-based technique for estimating AST using optical coherence tomography (OCT) landmarks. Methods: The AST was determined across four meridians in 62 participants (aged 20-37 years) with a swept-source OCT and a noncontact optical biometer at a mean ± SD distance of 3.13 ± 0.88 mm from the limbus. The biometer's graticule was focused and aligned with the anterior scleral reflex, which led to the generation of four prominent A-scan peaks: P1 (anterior bulbar conjunctiva), P2 (anterior episclera), P3 (anterior margin of anterior sclera), and P4 (posterior margin of anterior sclera), which were analyzed and compared with the corresponding OCT landmarks to determine tissue thickness. Results: The AST measurements between biometer and OCT correlated for all meridians (r ≥ 0.70, overall r = 0.82; coefficient of variation [CV], 9%-12%; P < 0.01). The mean difference ± SD between two instruments for overall AST measures was 3 ± 2.8 µm (range, -18 to +16 µm; lower limits of agreement, -89 to +83 µm; P = 0.23) across all meridians. The mean ± SE AST with both instruments was found to be thickest at the inferior (562 ± 7 µm and 578 ± 7 µm) and thinnest at the superior (451 ± 7 µm and 433 ± 6 µm) meridian. The biometer demonstrated good intrasession (CV, 8.4%-9.6%) and intersession (CV, 7.9%-13.3%) repeatability for AST measurements across all meridians. Conclusions: The noncontact optical biometer, which is typically used to determine axial length, is capable of accurately estimating AST based on OCT landmarks. Translational Relevance: The high-resolution optical biometers can demonstrate wider application in the field of myopia research and practice to determine AST.

Accuracy and Precision of New Optical Biometer Designed for Myopia Management in Measurement of Ocular Biometry.

SIGNIFICANCE: This study provides information about the repeatability of Myopia Master (Oculus, Wetzlar, Germany) and its agreement with Lenstar LS900, which might be useful for the practitioners involved in myopia management. PURPOSE: Myopia Master is a new optical biometer that measures ocular biometry and refractive error. The purpose of this study was to assess its repeatability (intrasession and short-term intersession) and its agreement with Lenstar LS900 for the measurement of axial length and corneal curvature. METHODS: A total of 304 participants including 254 children (mean ± standard deviation age, 13.7 ± 1.6 years) and 50 adults (24 ± 2.9 years) underwent measurements on Myopia Master and Lenstar LS900 to obtain axial length, flat K, and steep K. On a subset of 30 participants, measurements were obtained with Myopia Master in two sessions that were spread over 10 minutes to assess the short-term intersession repeatability. RESULTS: The mean standard deviation of Myopia Master in the measurement of axial length in the total sample was 0.01 mm for intrasession, when the best three measurements were considered. The short-term intersession mean standard deviation for axial length, flat K, and steep K was 0.06 mm, 0.15 D, and 0.21 D, respectively. There were statistically significant differences in mean values of axial length (-0.04 ± 0.06 mm), flat K (-0.07 ± 0.15 D), and steep K (-0.24 ± 0.29 D) between Lenstar LS900 and Myopia Master, with the Lenstar providing slightly longer axial length and steeper K values. Adults showed better repeatability with Myopia Master and better agreement between the biometers for axial length measurement than children. Neither axial length nor refractive error influenced the repeatability or agreement. CONCLUSIONS: Myopia Master is repeatable for the measurement of axial length and corneal curvature. Considering the differences in axial length between the Myopia Master and Lenstar LS900, caution must be applied when these biometers are used interchangeably.

Is There Any Association between Nutrition and Myopia? A Systematic Review.

SIGNIFICANCE: This systematic review highlights the possible role of nutrition in myopia based on qualitative analysis of vast and diverse literature that investigated this association. PURPOSE: We systematically reviewed the outcomes of the studies that previously investigated the association between nutrition and myopia. METHODS: EMBASE, MEDLINE, and PubMed were searched by two independent authors to identify cross-sectional, cohort, retrospective, or interventional studies that assessed the association of nutrition with myopia from inception to the year 2021. Furthermore, the reference list of the included articles was screened. The data from the included studies were extracted, and qualitative analysis was performed. Quality assessment for noninterventional studies and interventional trials was performed using the Newcastle-Ottawa Scale and Cochrane RoB 2, respectively. RESULTS: Twenty-seven articles were included in the review. Most of the nutrients and dietary elements investigated in noninterventional studies showed inconsistencies in their association with myopia, with the majority indicating no association. Nine studies showed a significant association of diverse nutrients and dietary elements with either an increase (odds ratio, 1.07) or a decrease (odds ratio, 0.5 to 0.96) in the risk of myopia development. However, a majority of these studies have minimal odds ratios with wider or overlapping confidence intervals, implicating weaker associations. All three nutrients and dietary elements assessed in the interventional trial had implications for myopia control, with two trials indicating a clinically minimal effect. CONCLUSIONS: This review implies that there is some evidence to indicate a potential influence of specific nutrients and dietary elements in myopia development, which are supported by several theories. However, given the vast, diverse, and complex nature of nutrition, more systematic investigation is warranted to comprehend the extent to which these specific nutrients and dietary elements are associated with myopia through longitudinal studies by subduing the limitations in the existing literature.

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.

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.

Association between relative peripheral refraction and corresponding electro-retinal signals.

PURPOSE: Considering the potential role of the peripheral retina in refractive development and given that peripheral refraction varies significantly with increasing eccentricity from the fovea, we investigated the association between relative peripheral refraction (RPR) and corresponding relative peripheral multifocal electroretinogram (mfERG) responses (electro-retinal signals) from the central to the peripheral retina in young adults. METHODS: Central and peripheral refraction using an open-field autorefractor and mfERG responses using an electrophysiology stimulator were recorded from the right eyes of 17 non-myopes and 24 myopes aged 20-27 years. The relative mfERG N1, P1 and N2 components (amplitude density and implicit time) of a mfERG waveform were compared with the corresponding RPR measurements at the best-matched eccentricities along the principal meridians, that is at the fovea (0°), horizontal (±5°, ±10° and ± 25°) and vertical meridians (±10° and ± 15°). RESULTS: The mean absolute mfERG N1, P1 and N2 amplitude densities (nV/deg2 ) were maximum at the fovea in both non-myopes (N1: 57.29 ± 14.70 nV/deg2 , P1: 106.29 ± 24.46 nV/deg2 , N2: 116.41 ± 27.96 nV/deg2 ) and myopes (N1: 56.25 ± 15.79 nV/deg2 , P1: 100.79 ± 30.81 nV/deg2 , N2: 105.75 ± 37.91 nV/deg2 ), which significantly reduced with increasing retinal eccentricity (p < 0.01). No significant association was reported between the RPR and corresponding relative mfERG amplitudes at each retinal eccentricity (overall Pearson's correlation, r = -0.25 to 0.26, p ≥ 0.09). In addition, the presence of relative peripheral myopia or hyperopia at extreme peripheral retinal eccentricities did not differentially influence the corresponding relative peripheral mfERG amplitudes (p ≥ 0.24). CONCLUSIONS: Relative peripheral mfERG signals are not associated with corresponding RPR in young adults. It is plausible that the electro-retinal signals may respond to the presence of absolute hyperopia (and not relative peripheral hyperopia), which requires further investigation.

Near work, light levels and dioptric profile - Which factor dominates and influences the short-term changes in axial length?

PURPOSE: Given the agonistic nature of near work to promote axial elongation and the antagonistic nature of time outdoors to prevent myopia, we aimed to investigate the following: (a) how the short-term effect of near work performed outdoors (Experiment 1) influences axial length and (b) how near work performed in two different dioptric profiles (uncluttered and cluttered) alters the changes in central axial length (Experiment 2). METHODS: Forty-six adults (age range: 19-32 years) participated in the study. In Experiment 1, 22 participants completed a 15-min distance task and a reading task in both the outdoor (~30,000 lux) and indoor (~70 lux) locations. In Experiment 2, 24 participants performed the same reading task at a study desk in uncluttered and cluttered reading environments. Pre- and post-task ocular biometry measurements were performed for each session using a non-contact biometer. RESULTS: In Experiment 1, a significant increase in axial length from baseline was found after performing reading tasks in both outdoor (mean ± SEM: +12.3 ± 3.4 µm, p = 0.001) and indoor locations (+11.9 ± 3.1 µm, p = 0.001). In Experiment 2, axial length increased significantly from baseline to post reading task, in both uncluttered (+17.9 ± 3.5 µm, p < 0.001) and cluttered reading environments (+19.2 ± 2.9 µm, p < 0.001). No significant changes in axial length were observed either between outdoor and indoor locations (p = 0.92) or between the uncluttered and cluttered reading environment (p = 0.75). CONCLUSION: Independent of light intensity (outdoor or indoor location) and dioptric profile of the near-work environment (uncluttered or cluttered), a 15-min reading task led to a significant increase in axial length. While the long-term effects of these findings need to be evaluated, practitioners should emphasise how near work can reduce the beneficial effects of time outdoors, while providing recommendations related to time outdoors for myopia control.

Interventions for myopia control in children: a living systematic review and network meta-analysis.

BACKGROUND: Myopia is a common refractive error, where elongation of the eyeball causes distant objects to appear blurred. The increasing prevalence of myopia is a growing global public health problem, in terms of rates of uncorrected refractive error and significantly, an increased risk of visual impairment due to myopia-related ocular morbidity. Since myopia is usually detected in children before 10 years of age and can progress rapidly, interventions to slow its progression need to be delivered in childhood. OBJECTIVES: To assess the comparative efficacy of optical, pharmacological and environmental interventions for slowing myopia progression in children using network meta-analysis (NMA). To generate a relative ranking of myopia control interventions according to their efficacy. To produce a brief economic commentary, summarising the economic evaluations assessing myopia control interventions in children. To maintain the currency of the evidence using a living systematic review approach.  SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register), MEDLINE; Embase; and three trials registers. The search date was 26 February 2022.  SELECTION CRITERIA: We included randomised controlled trials (RCTs) of optical, pharmacological and environmental interventions for slowing myopia progression in children aged 18 years or younger. Critical outcomes were progression of myopia (defined as the difference in the change in spherical equivalent refraction (SER, dioptres (D)) and axial length (mm) in the intervention and control groups at one year or longer) and difference in the change in SER and axial length following cessation of treatment ('rebound').  DATA COLLECTION AND ANALYSIS: We followed standard Cochrane methods. We assessed bias using RoB 2 for parallel RCTs. We rated the certainty of evidence using the GRADE approach for the outcomes: change in SER and axial length at one and two years. Most comparisons were with inactive controls. MAIN RESULTS: We included 64 studies that randomised 11,617 children, aged 4 to 18 years. Studies were mostly conducted in China or other Asian countries (39 studies, 60.9%) and North America (13 studies, 20.3%). Fifty-seven studies (89%) compared myopia control interventions (multifocal spectacles, peripheral plus spectacles (PPSL), undercorrected single vision spectacles (SVLs), multifocal soft contact lenses (MFSCL), orthokeratology, rigid gas-permeable contact lenses (RGP); or pharmacological interventions (including high- (HDA), moderate- (MDA) and low-dose (LDA) atropine, pirenzipine or 7-methylxanthine) against an inactive control. Study duration was 12 to 36 months. The overall certainty of the evidence ranged from very low to moderate. Since the networks in the NMA were poorly connected, most estimates versus control were as, or more, imprecise than the corresponding direct estimates. Consequently, we mostly report estimates based on direct (pairwise) comparisons below. At one year, in 38 studies (6525 participants analysed), the median change in SER for controls was -0.65 D. The following interventions may reduce SER progression compared to controls: HDA (mean difference (MD) 0.90 D, 95% confidence interval (CI) 0.62 to 1.18), MDA (MD 0.65 D, 95% CI 0.27 to 1.03), LDA (MD 0.38 D, 95% CI 0.10 to 0.66), pirenzipine (MD 0.32 D, 95% CI 0.15 to 0.49), MFSCL (MD 0.26 D, 95% CI 0.17 to 0.35), PPSLs (MD 0.51 D, 95% CI 0.19 to 0.82), and multifocal spectacles (MD 0.14 D, 95% CI 0.08 to 0.21). By contrast, there was little or no evidence that RGP (MD 0.02 D, 95% CI -0.05 to 0.10), 7-methylxanthine (MD 0.07 D, 95% CI -0.09 to 0.24) or undercorrected SVLs (MD -0.15 D, 95% CI -0.29 to 0.00) reduce progression.  At two years, in 26 studies (4949 participants), the median change in SER for controls was -1.02 D. The following interventions may reduce SER progression compared to controls: HDA (MD 1.26 D, 95% CI 1.17 to 1.36), MDA (MD 0.45 D, 95% CI 0.08 to 0.83), LDA (MD 0.24 D, 95% CI 0.17 to 0.31), pirenzipine (MD 0.41 D, 95% CI 0.13 to 0.69), MFSCL (MD 0.30 D, 95% CI 0.19 to 0.41), and multifocal spectacles  (MD 0.19 D, 95% CI 0.08 to 0.30). PPSLs (MD 0.34 D, 95% CI -0.08 to 0.76) may also reduce progression, but the results were inconsistent. For RGP, one study found a benefit and another found no difference with control. We found no difference in SER change for undercorrected SVLs (MD 0.02 D, 95% CI -0.05 to 0.09). At one year, in 36 studies (6263 participants), the median change in axial length for controls was 0.31 mm. The following interventions may reduce axial elongation compared to controls: HDA (MD -0.33 mm, 95% CI -0.35 to 0.30), MDA (MD -0.28 mm, 95% CI -0.38 to -0.17), LDA (MD -0.13 mm, 95% CI -0.21 to -0.05), orthokeratology (MD -0.19 mm, 95% CI -0.23 to -0.15), MFSCL (MD -0.11 mm, 95% CI -0.13 to -0.09), pirenzipine (MD -0.10 mm, 95% CI -0.18 to -0.02), PPSLs (MD -0.13 mm, 95% CI -0.24 to -0.03), and multifocal spectacles (MD -0.06 mm, 95% CI -0.09 to -0.04). We found little or no evidence that RGP (MD 0.02 mm, 95% CI -0.05 to 0.10), 7-methylxanthine (MD 0.03 mm, 95% CI -0.10 to 0.03) or undercorrected SVLs (MD 0.05 mm, 95% CI -0.01 to 0.11) reduce axial length. At two years, in 21 studies (4169 participants), the median change in axial length for controls was 0.56 mm. The following interventions may reduce axial elongation compared to controls: HDA (MD -0.47mm, 95% CI -0.61 to -0.34), MDA (MD -0.33 mm, 95% CI -0.46 to -0.20), orthokeratology (MD -0.28 mm, (95% CI -0.38 to -0.19), LDA (MD -0.16 mm, 95% CI -0.20 to  -0.12), MFSCL (MD -0.15 mm, 95% CI -0.19 to -0.12), and multifocal spectacles (MD -0.07 mm, 95% CI -0.12 to -0.03). PPSL may reduce progression (MD -0.20 mm, 95% CI -0.45 to 0.05) but results were inconsistent. We found little or no evidence that undercorrected SVLs (MD -0.01 mm, 95% CI -0.06 to 0.03) or RGP (MD 0.03 mm, 95% CI -0.05 to 0.12) reduce axial length. There was inconclusive evidence on whether treatment cessation increases myopia progression. Adverse events and treatment adherence were not consistently reported, and only one study reported quality of life. No studies reported environmental interventions reporting progression in children with myopia, and no economic evaluations assessed interventions for myopia control in children. AUTHORS' CONCLUSIONS: Studies mostly compared pharmacological and optical treatments to slow the progression of myopia with an inactive comparator. Effects at one year provided evidence that these interventions may slow refractive change and reduce axial elongation, although results were often heterogeneous. A smaller body of evidence is available at two or three years, and uncertainty remains about the sustained effect of these interventions. Longer-term and better-quality studies comparing myopia control interventions used alone or in combination are needed, and improved methods for monitoring and reporting adverse effects.

ANTECEDENTES: La miopía es un defecto de refracción frecuente, en el que el alargamiento del globo ocular hace que los objetos lejanos aparezcan borrosos. La creciente prevalencia de la miopía es un problema de salud pública mundial cada vez mayor, en cuanto a tasas de defectos de refracción no corregidos y un significativamente mayor riesgo de discapacidad visual debido a la morbilidad ocular relacionada con la miopía. Dado que la miopía se suele detectar en niños antes de los 10 años y puede evolucionar rápidamente, las intervenciones para frenar su avance se deben realizar en la infancia. OBJETIVOS: Evaluar la eficacia comparativa de las intervenciones ópticas, farmacológicas y ambientales para frenar la progresión de la miopía en niños mediante un metanálisis en red (MAR). Generar una clasificación relativa de las intervenciones de control de la miopía en función de su eficacia. Elaborar un breve comentario económico que resuma las evaluaciones económicas de las intervenciones de control de la miopía en niños. Mantener la vigencia de la evidencia mediante un enfoque de revisión sistemática continua. MÉTODOS DE BÚSQUEDA: Se realizaron búsquedas en CENTRAL (que contiene el Registro de ensayos del Grupo Cochrane de Salud ocular y de la visión [Cochrane Eyes and Vision]), MEDLINE; Embase; y en tres registros de ensayos. La fecha de búsqueda fue el 26 de febrero de 2022. CRITERIOS DE SELECCIÓN: Se incluyeron ensayos controlados aleatorizados (ECA) de intervenciones ópticas, farmacológicas y ambientales para retrasar la progresión de la miopía en niños de hasta 18 años. Los desenlaces fundamentales fueron la progresión de la miopía (definida como la diferencia en el cambio del equivalente esférico de la refracción [EER, dioptrías (D)] y la longitud axial [mm] en los grupos de intervención y control al año o más) y la diferencia en el cambio del EER y la longitud axial tras el cese del tratamiento ("rebote"). OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Se utilizaron los métodos Cochrane estándar. El sesgo se evaluó mediante la herramienta RoB 2 en el caso de los ECA paralelos. La certeza de la evidencia se calificó mediante el método GRADE para los desenlaces: cambio del EER y la longitud axial al año y a los dos años. La mayoría de las comparaciones se realizaron con controles inactivos. RESULTADOS PRINCIPALES: Se incluyeron 64 estudios que asignaron al azar a 11 617 niños de cuatro a 18 años de edad. Los estudios se realizaron principalmente en China u otros países asiáticos (39 estudios; 60,9%) y Norteamérica (13 estudios; 20,3%). Cincuenta y siete estudios (89%) compararon intervenciones de control de la miopía (gafas multifocales, gafas periféricas plus [PPSL por sus siglas en inglés], gafas monofocales [SVL por sus siglas en inglés] subcorregidas, lentes de contacto multifocales blandas [MFSCL por sus siglas en inglés], ortoqueratología, lentes de contacto rígidas permeables al gas [RGP por sus siglas en inglés]); o intervenciones farmacológicas (incluidas atropina a dosis alta, media y baja, pirenzipina o 7­metilxantina) contra un control inactivo. La duración de los estudios fue de 12 a 36 meses. La certeza global de la evidencia varió entre muy baja y moderada. Debido a que las redes del MAR estaban mal conectadas, la mayoría de las estimaciones versus control fueron tan imprecisas o más que las correspondientes estimaciones directas. En consecuencia, a continuación se presentan principalmente estimaciones basadas en comparaciones directas (por pares). Al año, en 38 estudios (6525 participantes analizados), la mediana del cambio del EER para los controles fue de ­0,65 D. Las siguientes intervenciones podrían reducir la progresión del EER en comparación con los controles: atropina a dosis alta (diferencia de medias [DM] 0,90 D; intervalo de confianza [IC] del 95%: 0,62 a 1,18), atropina a dosis media (DM 0,65 D; IC del 95%: 0,27 a 1,03), atropina a dosis baja (DM 0,38 D; IC del 95%: 0,10 a 0,66), pirenzipina (DM 0,32 D; IC del 95%: 0,15 a 0,49), MFSCL (DM 0,26 D; IC del 95%: 0,17 a 0,35), PPSL (DM 0,51 D; IC del 95%: 0,19 a 0,82) y gafas multifocales (DM 0,14 D; IC del 95%: 0,08 a 0,21). Por el contrario, hubo poca o ninguna evidencia de que las RGP (DM 0,02 D; IC del 95%: ­0,05 a 0,10), la 7­metilxantina (DM 0,07 D; IC del 95%: ­0,09 a 0,24) o las SVL subcorregidas (DM ­0,15 D; IC del 95%: ­0,29 a 0,00) redujeran la progresión. A los dos años, en 26 estudios (4949 participantes), el cambio medio del EER para los controles fue de ­1,02 D. Las siguientes intervenciones podrían reducir la progresión del EER en comparación con los controles: atropina a dosis alta (DM 1,26 D; IC del 95%: 1,17 a 1,36), atropina a dosis media (DM 0,45 D; IC del 95%: 0,08 a 0,83), atropina a dosis baja (DM 0,24 D; IC del 95%: 0,17 a 0,31), pirenzipina (DM 0,41 D; IC del 95%: 0,13 a 0,69), MFSCL (DM 0,30 D; IC del 95%: 0,19 a 0,41) y gafas multifocales (DM 0,19 D; IC del 95%: 0,08 a 0,30). Las PPSL (DM 0,34 D; IC del 95%: ­0,08 a 0,76) también podrían reducir la progresión, pero los resultados no fueron consistentes. Para las RGP, un estudio encontró un efecto beneficioso y otro no encontró diferencias con el control. No se observaron diferencias en el cambio del EER para las SVL subcorregidas (DM 0,02 D; IC del 95%: ­0,05 a 0,09). Al año, en 36 estudios (6.263 participantes), el cambio medio en la longitud axial de los controles fue de 0,31 mm. Las siguientes intervenciones podrían reducir la elongación axial en comparación con los controles: atropina a dosis alta (DM ­0,33 mm; IC 95%: ­0,35 a 0,30), atropina a dosis media (DM ­0,28 mm; IC 95%: ­0,38 a ­0,17), atropina a dosis baja (DM ­0,13 mm; IC 95%: ­0,21 a ­0,05), ortoqueratología (DM ­0,19 mm; IC 95%: ­0,23 a ­0,15), MFSCL (DM ­0,11 mm; IC del 95%: ­0,13 a ­0,09), pirenzipina (DM ­0,10 mm; IC del 95%: ­0,18 a ­0,02), PPSL (DM ­0,13 mm; IC del 95%: ­0,24 a ­0,03) y gafas multifocales (DM ­0,06 mm; IC del 95%: ­0,09 a ­0,04). Se encontró poca o ninguna evidencia de que las RGP (DM 0,02 mm; IC del 95%: ­0,05 a 0,10), la 7­metilxantina (DM 0,03 mm; IC del 95%: ­0,10 a 0,03) o las SVL subcorregidas (DM 0,05 mm; IC del 95%: ­0,01 a 0,11) reduzcan la longitud axial. A los dos años, en 21 estudios (4169 participantes), la mediana del cambio en la longitud axial de los controles fue de 0,56 mm. Las siguientes intervenciones podrían reducir la elongación axial en comparación con los controles: atropina a dosis alta (DM ­0,47 mm; IC del 95%: ­0,61 a ­0,34), atropina a dosis media (DM ­0,33 mm; IC del 95%: ­0,46 a ­0,20), ortoqueratología (DM ­0,28 mm; IC del 95%: ­0,38 a ­0,19), atropina a dosis baja (DM ­0,16 mm; IC del 95%: ­0,20 a ­0,12), MFSCL (DM ­0,15 mm; IC del 95%: ­0,19 a ­0,12) y gafas multifocales (DM ­0,07 mm; IC del 95%: ­0,12 a ­0,03). Las PPSL podrían reducir la progresión (DM ­0,20 mm; IC del 95%: ­0,45 a 0,05), pero los resultados no fueron consistentes. Se encontró poca o ninguna evidencia de que las SVL subcorregidas (DM ­0,01 mm; IC del 95%: ­0,06 a 0,03) o las RGP (DM 0,03 mm; IC del 95%: ­0,05 a 0,12) reduzcan la longitud axial. No hubo evidencia concluyente sobre si el abandono del tratamiento aumenta la progresión de la miopía. Los eventos adversos y la adherencia al tratamiento no se comunicaron de forma consistente, y solo un estudio informó sobre la calidad de vida. Ningún estudio proporcionó información sobre intervenciones ambientales que informaran sobre la progresión en niños con miopía y ninguna evaluación económica analizó intervenciones para el control de la miopía en niños. CONCLUSIONES DE LOS AUTORES: La mayoría de los estudios compararon tratamientos farmacológicos y ópticos para enlentecer la progresión de la miopía con un comparador inactivo. Los efectos al año demostraron que estas intervenciones podrían ralentizar el cambio refractivo y reducir el alargamiento axial, aunque a menudo los resultados fueron heterogéneos. El conjunto de evidencia disponible a los dos o tres años fue más escaso, y persiste la incertidumbre sobre el efecto sostenido de estas intervenciones. Se necesitan estudios a más largo plazo y de mejor calidad que comparen las intervenciones para el control de la miopía utilizadas solas o en combinación, así como métodos mejorados de seguimiento y notificación de los efectos adversos.

Influence of location, season and time of day on the spectral composition of ambient light: Investigation for application in myopia.

PURPOSE: Given the possible role of spectral composition of light and myopia, this study aimed at investigating the variation in the spectral composition of ambient light in different (a) outdoor/indoor locations, (b) time of a day and (c) seasons. METHODS: The spectral power distribution (SPD), categorised into short (380-500 nm), middle (505-565 nm) and long wavelengths (625-780 nm), was recorded using a handheld spectrometer at three outdoor locations ('open playground', 'under shade of tree' and 'canopy') and three indoor locations ('room with multiple windows', 'closed room' and 'closed corridor'). Readings were taken at five different time points (3-h intervals between 6:30 and 18:00 hours) on two days, each during the summer and monsoon seasons. RESULTS: The overall median SPD (IQR [25th-75th percentile] W/nm/m2 ) across the three outdoor locations (0.11 [0.09, 0.12]) was 157 times higher than that of the indoor locations (0.0007 [0.0001, 0.001]). Considerable locational, diurnal and seasonal variation was observed in the distribution of the median SPD value, with the highest value being recorded in the 'open playground' (0.27 [0.21, 0.28]) followed by 'under shade of tree' (0.083 [0.074, 0.09]), 'canopy' (0.014 [0.012, 0.015]) and 'room with multiple windows' (0.023 [0.015, 0.028]). The relative percentage composition of short, middle and long wavelengths was similar in both the outdoor and indoor locations, with the proportion of middle wavelengths significantly higher (p < 0.01) than short and long wavelengths in all the locations, except 'canopy'. CONCLUSION: Irrespective of variation in SPD values with location, time, day and season, outdoor locations always exhibited significantly higher spectral power than indoor locations. The relative percentage composition of short, middle and long wavelengths of light was similar across all locations. These findings establish a foundation for future research to understand the relationship between spectral power and the development of myopia.

Do Anisometropic Eyes Have Steeper Retinas Than Their Isometropic Counterparts?

SIGNIFICANCE: Our findings suggest that retinal shapes of the eyes of anisometropes are not different from that of the eyes of isometropes with the same refractions. PURPOSE: We investigated ( a ) intereye differences in relative peripheral eye lengths between isometropes and anisometropes and ( b ) if the retinal shape is different between isometropic and anisometropic eyes with the same central refraction. METHODS: Central and peripheral eye lengths were determined along the horizontal meridian in 10° intervals out to ±30° using a noncontact biometer in 28 isometropes and 16 anisometropes. Retinal coordinates were estimated using these eye lengths and ray tracing. Retinal shape was determined in terms of vertex radius of curvature ( Rv ), asphericity ( Q ), and equivalent radius of curvature ( REq ). Linear regression was determined for the REq as functions of central refraction in a subset of isometropic and anisometropic eyes having the same refraction. RESULTS: The differences in relative peripheral eye lengths between the two eyes of anisometropes were significantly greater than for isometropes at ±30° eccentricities. Higher myopic eyes of anisometropes had smaller Rv , more negative Q , and smaller REq than the lower myopic eyes for both isometropes and anisometropes (mean ± standard error of the mean: Rv , 9.8 ± 0.5 vs. 11.7 ± 0.4 mm [ P = .002]; Q , -1.1 ± 0.2 vs. -0.5 ± 0.2 [ P = .03]; REq , 11.5 ± 0.3 vs. 12.4 ± 0.2 mm [ P = .01]). Intercepts and slopes of the linear regressions of REq in anisometropes and their isometropic counterparts with the same refraction were not significantly different from each other ( P > .05). CONCLUSIONS: Higher myopic eyes of anisometropes had similar retina shapes along the horizontal meridian to those of isometropic eyes with the same refraction.

Development and validation of a 'MyLyt' wearable light tracking device.

PURPOSE: We developed a clip-on light tracker (MyLyt) for estimating light exposure in real time. This study aimed at validating and investigating the feasibility of using MyLyt in children and adults. METHOD: The study was conducted in two phases. Phase 1 involved validation against a factory-calibrated digital lux meter in three separate conditions: controlled environmental set-up, outdoors and indoors where intra-test (two measurements by the same tracker), inter-test (measurements among trackers) and inter-device (MyLyt tracker and lux meter) validations were conducted. Phase 2 involved a feasibility study where MyLyt was used in a real-world setting by 21 adults and 8 children. Participants were asked to log their real-time movements in an 'activity diary', which were correlated with the lux levels measured by the tracker. RESULTS: A strong positive correlation and non-significant difference in the recorded mean illuminance levels were observed during intra-test (inter-class correlation: 1.00, p = 0.99), inter-test (0.91-1.00, p > 0.15) and inter-device (0.91-1.00, p > 0.56) validation in all three testing conditions (p > 0.49), except the indoor location. While the lux level measured by MyLyt was significantly higher than that of the lux meter (p < 0.01) in the indoor locations, differences were minimal and clinically insignificant. A Bland-Altman plot showed a minimal mean difference (95% limits of agreement) between the MyLyt tracker and lux meter in all three conditions (controlled environmental set-up: 641 [-949, 2230], outdoor: 74 [-2772, 2920] and indoor: -35 [-151, 80] lux). Phase 2 validation showed an expected illuminance level against the corresponding location with high sensitivity (97.8%) and specificity (99%) to accurately differentiate between outdoor and indoor locations. CONCLUSION: The MyLyt tracker showed good repeatability, strong correlation and comparable values with the lux meter in the three tested conditions, making it suitable for tracking light exposure patterns for both research and clinical purposes.