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

Purpose: It is common to hear talk of 'responders' and 'non‐responders' with respect to myopia control interventions. We consider the reality of distinguishing these sub‐groups using data from the first year of the Low‐concentration Atropine for Myopia Progression (LAMP) study. Methods: The first year of the LAMP study was a robustly designed, placebo‐controlled trial of three different low concentrations of atropine using a large sample size (N > 100 randomised to each group). The authors subsequently published mean axial elongation and myopia progression rates by age group. We used these data to calculate efficacy in terms of both absolute reduction in myopic progression and absolute reduction in axial elongation for each of the different atropine concentrations at each age group. We then compared these efficacy data to the overall progression for each of the two progression metrics. Results: Plotting efficacy as a function of overall myopia progression and axial elongation for each of the different atropine concentrations demonstrates the invariant nature of efficacy, in terms of clinically meaningful reduction in progression, despite a substantial range of underlying overall progression. That is, faster progressors—the so‐called non‐responders—achieved similar reduction in axial elongation and myopia progression as the slower progressors—the so‐called responders—within the various atropine treatment groups. Conclusion: The use of the terms, responders and non‐responders, during myopia progression interventions is not supported by evidence. Those designated as such may simply be slower or faster progressors, who, on average achieve the same benefit from treatment. [ABSTRACT FROM AUTHOR]

Purpose: When myopia control treatment is discontinued, progression will increase, but does it revert to expected values based on the age and race of the child or does it accelerate further? The latter scenario is considered a rebound. Methods: A PubMed search was conducted with the words 'rebound' and 'myopia control', identifying further papers from reviews. Inclusion was limited to prospective studies with ≥6 months of treatment, ≥3 months of data following cessation and with axial length data, which allowed calculation of rebound. Nineteen studies were identified, comprising 24 treatment groups. In 10 studies, untreated control children were followed both throughout the treatment and cessation periods, allowing for a concurrent comparison group. In three studies, a control group was followed for 1 or 2 years and thereafter received the treatment under evaluation. Later, treatment ceased in the originally treated children. Finally, six studies were cross‐over designs. For these latter two study designs, initial axial elongation and myopia progression in the control group were extrapolated to the cessation period, accounting for annual slowing. Values from durations of <1 year were annualised. Results: The mean annualised rebound was +0.05 ± 0.10 mm and −0.09 ± 0.24 D for axial length and myopia progression, respectively, and these were correlated (r2 = 0.59, p < 0.001). Rebound was associated with 1‐year treatment efficacy (r2 = 0.43, p < 0.001). The mean annualised rebound with optical corrections was −0.01 ± 0.03 mm. Five of the six highest rebound values (≥0.14 mm) were from red light therapy and atropine studies. Rebound ranged from +0.03 to +0.14 mm for overnight orthokeratology. Conclusions: Consistent with previous statements, no evidence for rebound was found for myopia control spectacles and soft contact lenses. Future research should explore the influence of age and magnitude of treatment efficacy on rebound. [ABSTRACT FROM AUTHOR]

Background The prevalence of myopia is increasing worldwide. The purpose of this study was to evaluate the progression of myopia in teenagers and adults in France. Methods This nationwide prospective study followed 630 487 myopic adults and teenagers (mean age 43.4 years±18.2, 59.8% of women) between January 2013 and January 2019. Myopia and high myopia were defined as a spherical equivalent less than or equal to -0.50 and -6.00 diopters (D), respectively. Demographic data were collected at first visit and refractive characteristics were collected at each visit. Analysis of short-term progression (first 12 to 26 months postbaseline) was modelled using analysis of variance (ANOVA). Progression of myopia was stratified according to age, gender and spherical equivalent at first visit. Results Higher proportions of progressors were observed in the youngest age groups: 14-15 (18.2 %) and 16-17 years old (13.9 %). In multivariate analysis, after adjustment for over age, spherical equivalent and gender, the mean short-term progression decreased from -0.36 D in the 14-15 years age group to -0.13 D in the 28-29 years age group. Young age and higher myopia at baseline together were strongly associated with the risk of developing high myopia, the 5-year cumulative risk being 76% for youngest teenager with higher myopia status at baseline. Conclusion In this large cohort of myopic teenagers and adults, myopia progression was reported in 18.2% and 13.9% of the 14-15 and 16-17 age groups, respectively. The risk to develop high myopia was higher for younger individuals with higher myopia at baseline examination. [ABSTRACT FROM AUTHOR]