The Response

‍ ‍

According to WHO estimates at the beginning of their VISION 2020 program, about 19 million children under the age of 15 had visual impairment, with uncorrected refractive error as the leading cause of around 43%. This can affect children’s learning at school. A randomised controlled trial conducted in China found higher scores in mathematics tests in children who received glasses compared to control children without glasses to correct their refractive error (Ma, 2014).

Myopia Progression Without Treatment

One of the pioneering longitudinal studies on myopia in U.S. children was the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (Mutti, 2024) study, where researchers followed a group of children aged 5-14 years annually for up to 8 years. Key findings include that the age at which a child became myopic ranged from 7 to 16 years, and the incidence of fresh cases increased annually until age 11, then decreased thereafter. Among all non-myopic children at the start, 16.4% became myopic during the school years. Six-year-old children who were mildly farsighted (still hyperopic at +0.75 D) were at increased risk of developing myopia, while those who remained farsighted until age 9 tended to avoid myopia altogether.

The other important study was the Collaborative Observational Study of Myopia in COMET Children (Scheiman, 2016) which showed schoolchildren with myopia progressed by 0.50 D per year on average while wearing normal spectacles. Younger children progressed faster and developed a higher level of myopia. The average age when myopia progression stopped was 15 years. The average amount of myopia at the end of progression was -4.87 D. Studies of this kind show that without intervention, myopic eyes continue to worsen throughout childhood.

Treatment of Myopia in Children

Glasses have been the standard treatment to correct vision in myopia for hundreds of years. For children, plastic lenses made of polycarbonate are preferred to glass as being more durable and shatter-proof. In addition, they almost always provide full ultraviolet (UV) radiation protection. Single-vision lenses, meaning that there is only one focusing power across the whole lens, are most used.

Blue-light blocking lenses have become popular, but there is no evidence that they reduce eye strain, improve sleep quality, nor protect against retina damage in children. Photochromic lenses, which change from light to dark in the presence of UV light, offer comfort from glare but have no effect on myopic change.

Contact lenses are another option for older children. They can be made of hard plastic, called rigid gas permeable (RGP) lenses, or a softer material called hydrogel. They are worn on the clear front surface of the eye, called the cornea, with soft lenses draping over the entire cornea. While they are generally safe for children, there are problems arising from overuse and the risk of infection. It is recommended that children use contact lenses in the teen years at parents’ discretion, unless treatment for a specific eye condition was needed.

Laser corneal refractive surgery and lens implantation into the eye with or without removing the lens are procedures that can treat myopia in adults but are not suitable for children. While the vision can be corrected with these surgeries, it is worth remembering that they do not remove the risk of pathological myopia. It is therefore imperative that the degree of myopia be kept as low as possible before children reach adulthood.

Current evidence suggests that prescribing the full correction of myopia in children is recommended. There is some evidence that under-prescribing, or not wearing glasses at all, may actually promote myopia progression (Lawrenson, 2023). This may necessitate more frequent visits to the eye care professional for regular updates, especially during the early years when myopia is expected to progress the most.

Treatment Options to Slow Myopia Progression

New interventions to slow myopia progression have developed alongside more refined theories of how the growth of the eye is regulated. A suspected association between near work and myopia led to methods targeting the focusing power of the eye. The discovery that hyperopic defocus in the peripheral part of the retina may drive the eye to grow resulted in glasses and contact lenses designed to oppose this effect. Below are the most current treatment options, listed roughly in the order they entered clinical use and the reported impact each has on reducing myopia progression.

Progressive Addition Spectacles

The Correction of Myopia Evaluation Trial (COMET, 2013) was aimed at testing the theory that blur resulting from poor near-focusing ability in myopic eyes caused further progression. By giving myopic children progressive addition lenses, where the lower segment of the glasses increases the reading power, the image would become clearer at near and eye growth will therefore be slowed. This trial showed only a modest effect of about a 10-15% reduction in progression compared to wearing conventional glasses. However, for the first time, a randomised clinical trial showed that it was possible to alter myopia progression with active intervention.

Atropine 1% Eyedrops

Myopia has been associated with near work throughout history. Thus, it was presumed that if the focusing power of the eye was inhibited during close-up work, this might slow down myopia progression. Atropine 1% eyedrops have traditionally been used for this paralysing effect, besides dilating the pupil, and these effects can last up to 10 days. Initial studies showed its effectiveness at slowing myopia. However, it was interesting to note that the same effect was not seen with other eyedrops that also stop focusing. So, atropine 1% worked, but not in the way it was originally thought.   

The Atropine Treatment of Myopia (Chua, 2006) study from Singapore was a randomised controlled trial that showed after 2 years of treatment, atropine 1% drops reduced myopia progression by 77% compared to controls, one of the best effect sizes of any myopia intervention. The problem was that after stopping treatment, the eyes would start growing again, but at an even faster rate than before treatment (rebound phenomenon), catching up with the untreated group. There were also complaints of glare from pupil dilation and the inability to read without appropriate optical correction because treated eyes lose their focusing ability.

Low-dose Atropine

The same researchers from Singapore then proposed that if Atropine 1% was diluted, there would be less light sensitivity, better close-up vision, but will still be able to slow down myopia progression. The ATOM 2 (Chia, 2014) study therefore compared diluted compositions of 0.5% with 0.1% and used 0.01% atropine as a control group, applied to children aged 6 to 12 years with more than -2.00 D myopia. To their surprise, the atropine 0.01% group (diluted 100:1) also slowed myopia progression, but with almost negligible effects on light sensitivity and near focusing.

Although the initial treatment effect was better with the higher concentrations of atropine, the rebound effect was less, making the results comparable across all three concentrations. The treatment effect was calculated to be a 30-50% reduction in myopia progression using atropine 0.01%. This became the new atropine concentration of choice to treat myopia progression in children living in East Asia.

Orthokeratology

Orthokeratology (also known as ortho-k) lenses are hard RGP contact lenses that are worn overnight to reshape the cornea. The flattened central part of the cornea keeps its shape when the contact lens is removed, resulting in clear distance vision for most of the next day. However, the bowed peripheral part of the cornea creates a kind of myopic defocus for the peripheral retina, which is thought to be the mechanism by which these lenses work to slow down myopia progression.

The Retardation of Myopia in Orthokeratology (Cho, 2012) study compared children aged 6-10 years wearing ortho-k lenses versus conventional single-vision spectacles and found a 43% reduction in myopia progression. There is also a rebound phenomenon with ortho-k lenses, especially for children stopping before the age of 14. Users should also know there is a risk of corneal infection estimated to be about 14 per 10,000 uses.

Optimized Atropine

The search for the most ideal concentration of atropine, which combined myopia control with the least side-effects was the purpose of the Low-Concentration Atropine for Myopia Progression (Yam, 2019) study on children aged 4-12 years. The authors concluded that 0.05% atropine produced the best treatment effect at a rate of about 60-67% reduction in myopia progression, while the side-effects remained minimal. Rebound effect after stopping treatment was comparable to 0.01% atropine, meaning there was no downside in using the higher concentration.

Multifocal Contact Lens

The Bifocal Lenses in Nearsighted Kids (Berntsen, 2023) study was a randomised clinical trial comparing children aged 7-11 years wearing single-vision contact lenses versus multifocal contact lenses. The latter were commercially available contact lenses designed for users with presbyopia (need for reading glasses) but were used in children to create a peripheral myopic defocus, the prevailing theory of how an image can be optically manipulated to slow down myopia progression. The estimated treatment effect from this study was a 43% reduction in eye growth. Later, a variation of this type of contact lens called MiSight® was FDA-approved for children with myopia.

Peripheral Defocus Spectacles    

‍ ‍Besides contact lenses for changing peripheral defocus, various other spectacle lenses have been designed for myopia control. They all follow a similar principle of a central area for clear vision and a peripheral zone that produces myopic blur. They have the advantage of correcting high degrees of astigmatism compared to contact lenses, and they appear like normal glasses when worn. However, study results have been mixed.

One lens design called Defocus Incorporated Multiple Segments (DIMS) has shown promise. Randomised controlled trials conducted in Hong Kong (Lam, 2020) showed an approximate 50-60% reduction in myopia progression. As these are proprietary spectacle lenses, there are few independent studies to corroborate their results.

Repeated Low-level Red-light (RLRL) Therapy

RLRL therapy is a new and promising treatment for slowing myopia progression. It involves exposing eyes to red light delivered by a machine for 3 minutes, twice a day, 5 times a week (Jiang, 2022). The reduction effect has been reported to be around 60-75% in myopia progression. How it works is not fully known yet, but may include improvement of blood flow and/or biochemical changes in the retina. There is a rebound effect when treatment is stopped, and the long-term safety has yet to be established.

Summary

In the past 20 years, there has been a plethora of research activity into understanding how myopia develops and how to slow it down when progression has begun. Nevertheless, questions about when best to start, stop, or restart treatment remain. Options include glasses alone, multifocal optical corrections with contact lenses or glasses, atropine eyedrops, and light therapy. A summary table is provided here.

Which option families decide to choose will need to consider the accessibility, effectiveness, safety profile, and the cost of each intervention. Current treatments are not 100% effective and have rebound effects when stopped, so it is not always clear how long they should continue. The prolonged duration of treatment makes the study of their long-term safety even more important. What we do know is that myopia progresses faster in younger children, which makes identifying those at risk and preventing the onset of myopia that much more worthwhile.

(This page is educational and not a substitute for personalised advice from your eye care professional)

More Resources‍ ‍

References

Berntsen, D. A., Ticak, A., Sinnott, L. T., Chandler, M. A., Jones, J. H., Morrison, A., Jones-Jordan, L. A., Walline, J. J., Mutti, D. O., & BLINK Study Group. (2023). Peripheral defocus, pupil size, and axial eye growth in children wearing soft multifocal contact lenses in the BLINK Study. Investigative Ophthalmology & Visual Science, 64(14), 3.

Chia, A., Chua, W. H., Wen, L., Fong, A., Goon, Y. Y., & Tan, D. (2014). Atropine for the treatment of childhood myopia: Changes after stopping atropine 0.01%, 0.1% and 0.5%. American Journal of Ophthalmology, 157(2), 451–457.

Cho P, Cheung SW. Retardation of myopia in Orthokeratology (ROMIO) study: a 2-year randomized clinical trial. Invest Ophthalmol Vis Sci. 2012 Oct 11;53(11):7077-85.

Chua, W. H., Balakrishnan, V., Chan, Y. H., Tong, L., Ling, Y., Quah, B. L., & Tan, D. (2006). Atropine for the treatment of childhood myopia. Ophthalmology, 113(12), 2285–2291.

COMET Group. (2013). Myopia stabilization and associated factors among participants in the Correction of Myopia Evaluation Trial (COMET). Investigative Ophthalmology & Visual Science, 54(13), 7871–7884.

Jiang, Y., Zhu, Z., Tan, X., Kong, X., Zhong, H., Zhang, J., Xiong, R., Yuan, Y., Zeng, J., Morgan, I. G., & He, M. (2022). Effect of repeated low-level red-light therapy for myopia control in children: A multicenter randomized controlled trial. Ophthalmology, 129(5), 509–519.

Lam, C. S. Y., Tang, W. C., Tse, D. Y., Lee, R. P. K., Chun, R. K. M., Hasegawa, K., Qi, H., Hatanaka, T., & To, C. H. (2020). Defocus incorporated multiple segments (DIMS) spectacle lenses slow myopia progression: A 2-year randomized clinical trial. British Journal of Ophthalmology, 104(3), 363–368.

Lawrenson JG, Shah R, Huntjens B, Downie LE, Virgili G, Dhakal R, Verkicharla PK, Li D, Mavi S, Kernohan A, Li T, Walline JJ. Interventions for myopia control in children: a living systematic review and network meta-analysis. Cochrane Database Syst Rev. 2023 Feb 16;2(2):CD014758.

Ma X, Zhou Z, Yi H, Pang X, Shi Y, Chen Q, Meltzer ME, le Cessie S, He M, Rozelle S, Liu Y, Congdon N. Effect of providing free glasses on children's educational outcomes in China: cluster randomized controlled trial. BMJ. 2014 Sep 23;349:g5740.

Mutti DO, Sinnott LT, Cotter SA, Jones-Jordan LA, Kleinstein RN, Manny RE, Twelker JD, Zadnik K. Predicting the onset of myopia in children by age, sex, and ethnicity: Results from the CLEERE Study. Optom Vis Sci. 2024 Apr 1;101(4):179-186.

Scheiman, M., Gwiazda, J., Zhang, Q., Deng, L., Fern, K., Manny, R. E., Weissberg, E., & Hyman, L. (2016) Longitudinal changes in corneal curvature and its relationship to axial length in the Correction of Myopia Evaluation Trial (COMET) cohort, Journal of Optometry, 9(1), 13–21.

Yam, J. C., Jiang, Y., Tang, S. M., Law, A. K. P., Chan, J. J., Wong, E., Ko, S. T., Young, A. L., Tham, C. C., Chen, L. J., & Pang, C. P. (2019). Low-Concentration Atropine for Myopia Progression (LAMP) study: A randomized, double-blinded, placebo-controlled trial of 0.05%, 0.025%, and 0.01% atropine eye drops in myopia control. Ophthalmology, 126(1), 113–124.