As an optometrist, you are likely asked every day about a child’s myopia progression by concerned parents who want to know, “Is there anything we can do to stop their eyes from progressing?”
Currently, 20% of the global population (or about 1.5 billion people) is myopic with 163 million people having high myopia, which is defined as greater than −5.00 diopters (D). By 2050, it is projected that half of the global population will be myopic.1
Studies have demonstrated the most effective treatments for slowing myopia progression include orthokeratology, pharmacological agents, and soft contact lenses.2 Newer treatments, such as specially-designed spectacles or red-light therapy, have also shown promise.3,4
To be considered clinically significant, myopia management treatment options must decrease myopia progression by 50%.5
Factors contributing to myopia progression
While the factors influencing myopia progression are not yet fully understood, they are believed to be a combination of two leading causes: genetics and an imbalance of time spent doing near work versus time spent outdoors.
The connection between genetics and myopia progression
Myopia is more prevalent and severe in East Asian people when compared to Caucasians, especially in individuals of Chinese, Japanese, and Korean ancestry.6
Children with myopic parents are more likely to have myopia.5 Based on several studies of twins, including pairs of both Asian and Caucasian ancestry, heritability estimates ranged from 50% to 90%.
However, these same studies concluded: “It is hard to show anything but a modest effect on their etiologies. Thus we are still left with the impression that the influence of environment exerts a greater effect than does the concerted action of several genes.”7
More than 400 associated gene loci have been mapped for myopia and refractive errors via family linkage analyses, candidate gene studies, genome-wide association studies (GWAS), and next-generation sequencing (NGS). More gene investigations are needed to improve the understanding of gene components relative to the disease onset/susceptibility.6
The link between near work, time outdoors, and myopia
Environmental factors are considered to be a major determinant for myopia, especially in children, while genetic factors account for a small portion of myopia risk.
Time spent outdoors has been shown to delay the onset of myopia, and researchers believe it is because light induces dopamine release from the retina, which inhibits myopia elongation.8 Epidemiological studies indicate that increased outdoor activities and reduced work are important factors in controlling myopia incidence.6
In a randomized clinical trial, He and associates found that an additional 40 minutes of outdoor time per day achieved a 23% reduction in the incidence of myopia.9 Numerous studies have found a correlation between near work, low light, and increased myopia.10
Current treatments for myopic progression
Going back to the basics: orthokeratology
Orthokeratology has been approved in all countries to slow myopia progression by limiting axial elongation of the eye. Orthokeratology works by flattening the central area of the cornea and providing a clear image on the central retina while simultaneously the mid-peripheral cornea is steepened, imposing myopic defocus on the peripheral retina.11
Ortho-k has been shown to be more effective than single vision soft contacts, RGP lenses, or spectacles5 and is effective at decreasing myopic progression by more than 40%.2
Atropine for pharmacologic treatment
In the treatment of myopia, 0.05% Atropine had comparable results to that of high-dose atropine and is considered to be the most beneficial dosage for myopia treatment.12
While the exact mechanism of antimuscarinic agents, like atropine, is unknown, they are effective at reducing myopic eye growth in children,5 and fortunately, there are no significant side effects resulting from its use.2
Interestingly, trials were successful in also mitigating concerns that these children would be unable to perform near vision tasks while on this treatment. Only 6% of children on a 0.01% atropine dosage felt the need to request near vision spectacles to help with accommodation.5
Atropine use for myopia management is compound and considered “off-label” in the US, so your patient needs to sign an “informed consent” form for off-label treatment. Studies show that atropine can decrease myopia progression from 54% to 21%.5
Finding the right fit with soft contact lenses
Soft multifocal or aspheric contact lenses have become the standard treatment for most ECPs to slow myopic progression in children. Studies demonstrate that hyperopic defocus can induce excessive eye growth and myopia progression, while myopic defocus can slow or reverse eye growth.14
Studies have shown it is possible to manipulate eye growth when myopic defocus is presented simultaneously with an additional optical power. These coinciding optics are typically used with concentric alternating powers in a “dual-focus optics” zone design.13
The BLINK study showed that multifocal contacts with the full distance prescription combined with a +2.50 add were able to slow myopic progression, but new daily options are preferred by ECPs for ocular health in children.14
1) Coopervision MiSight
The Coopervision MiSight 1 Day Lens is designed with two treatment zones to create myopic defocus. When compared with a single vision lens, Coopervision MiSight 1 Day reduced myopia progression by 59% and resulted in a 52% reduction in average axial lengthening. Investigators also found that the lenses were safe for treatment in children with no severe cases of adverse ocular events.13
2) NaturalVue Enhanced Multifocal 1 Day
NaturalVue Multifocal 1 Day Contact Lenses (NVMF) are designed with approximately 8 diopters (D) to 11 D of relative plus power at the edge of the pupil, and approximately 20 D of relative plus power at the edge of the optic zone. The extended depth of focus (center distance) multifocal contact lens was effective in slowing myopic progression.
The average annualized amount of myopic progression before wearing the NVMF contact lenses was −0.85D per year, which was reduced to −0.04 D after wearing the NVMF lenses. Nearly 91% (90.6%) of the children who wore these contacts showed a 70% decrease or greater in myopic progression.15
3) ACUVUE Abiliti 1-Day Soft Therapeutic Lenses for Myopia Management
Although the ACUVUE Abiliti 1-Day Soft Therapeutic Lenses are not traditional concentric ring presbyopic design lenses, in a clinical study of children 7 to 12 years old, they were effective at slowing axial elongation by 0.105mm on average and myopia. Children in the study were required to wear the lens, at a minimum, 8 hours per day for 5 days per week.16 This lens is not yet available in the US but was approved in Canada in 2021.
Treatments using spectacles also show promise
A study from China also supports the use of aspheric lenslets over single-vision lenses to slow myopic progression in children. No treatment-related adverse events were reported.4 When compared to slightly aspherical lenslets (SAL) or single-vision spectacle lenses, highly aspherical lenslets (HAL) demonstrated efficacy in slowing axial length elongation by 64% and spherical equivalent refraction by 67% after 1 year.
Both highly and slightly aspherical spectacle lenses have a spherical front surface with 11 concentric rings formed by connecting aspherical lenslets. The area of the lens without lenslets provides distance correction. The geometry of aspherical lenslets has been calculated to generate an area of myopic defocus in front of the retina at any eccentricity, which serves as a myopia control signal.4
1) Essilor’s Stellest
While not currently available in the United States, Essilor’s Stellest spectacle lens was designated a “Breakthrough Device” by the FDA, which will allow for further research in the US and FDA review.
When compared to a single vision lens, Stellest is reported to slow myopia by approximately 63% for spherical equivalent refractive error and approximately 64% for axial length. The Stellest lens incorporates H.A.L.T. (Highly Aspherical Lenslet Target) technology to control myopia progression.17
2) MiYOSMART by HOYA
Currently, the MiYOSMART spectacle lens has not been approved for myopia management in the US but is available in Canada. MiYOSMART lenses feature D.I.M.S. (Defocus Incorporated Multiple Segments) Technology, which reportedly slows myopia by 52% (spherical equivalent) and axial length by 62% when compared to single vision spectacles.14
Red-light therapy: a new addition to myopia treatment options
While it is not yet a common treatment option in the United States, red-light therapy has shown promising results in slowing myopia progression when treated twice daily with 3 minute sessions, 5 days a week.3
Chinese investigators reported a 69.4% slowing in axial length elongation and 76.6% progression in myopic refraction. Treatment efficacy increased significantly with improved compliance. Researchers also documented that the treatments did not result in functional or structural damage in the children’s eyes.3
Alternative therapies to consider
Under correction of refractive error, gas permeable lenses and nutritional factors have been ineffective in slowing progression, according to recent studies.5,18
Trials investigating the effect of spending more time outdoors on slowing the progression of myopia have been mixed.5 Most studies indicated a later onset of myopia; however, these studies are difficult to compare because of their contrasting designs.
Additionally, a final assessment of the effect of outdoor time on progression cannot be made due to the relatively small number of studies that have dealt with the impact of increased outdoor time on myopia progression.
However, there is growing evidence for a link between increased time outdoors and a lower myopia incidence/prevalence as well as a later age of myopia onset.19 A 2020 study did conclude that prevalence and progression of myopia seems to be associated with the modulation of outdoor time.
In contrast to previous reviews, recent data also suggests that increased time outdoors can slow down myopia progression.19 A study performed among MiSight lens wearers indicated that time spent outdoors was a main factor in controlling axial eye growth in children.20
Conclusion
Myopia development and progression are due to genetic and environmental factors.
While many new novel treatments are expected in the future, our most successful treatments are currently orthokeratology, atropine, and soft lenses designed for myopia control.
All children should be encouraged to spend time outdoors, and near work should be performed with a focus on time allocation, lighting, and working distance.
References
- Rhee MK. Update on Myopia Control: The US Perspective. Eye Contact Lens. 2022 Mar 1;48(3):105-109. doi: 10.1097/ICL.0000000000000872. PMID: 35192563.
- Anderson, Richard, OD, Thomas Aller, OD, and Jeffrey J. Walline, OD. “Controlling Myopia, Changing Lives.” Review of Cornea and Contact Lenses. Review of Cornea and Contact Lens, 15 Sept. 2014. Web. 17 Jan. 2016. <http://reviewofcontactlenses.com/content/c/50427/>.
- Jiang Y, Zhu Z, Tan X, Kong X, Zhong H, Zhang J, Xiong R, Yuan Y, Zeng J, Morgan IG, He M. Effect of Repeated Low-Level Red-Light Therapy for Myopia Control in Children: A Multicenter Randomized Controlled Trial. Ophthalmology. 2022 May;129(5):509-519. doi: 10.1016/j.ophtha.2021.11.023. Epub 2021 Dec 1. PMID: 34863776.
- Bao J, Yang A, Huang Y, Li X, Pan Y, Ding C, Lim EW, Zheng J, Spiegel DP, Drobe B, Lu F, Chen H. One-year myopia control efficacy of spectacle lenses with aspherical lenslets. Br J Ophthalmol. 2022 Aug;106(8):1171-1176. doi: 10.1136/bjophthalmol-2020-318367. Epub 2021 Apr 2. PMID: 33811039.
- Smith MJ, Walline JJ. Controlling myopia progression in children and adolescents. Adolesc Health Med Ther. 2015 Aug 13;6:133-40. doi: 10.2147/AHMT.S55834. PMID: 26316834; PMCID: PMC4542412.
- Wang YM, Lu SY, Zhang XJ, Chen LJ, Pang CP, Yam JC. Myopia Genetics and Heredity. Children (Basel). 2022 Mar 9;9(3):382. doi: 10.3390/children9030382. PMID: 35327754; PMCID: PMC8947159.
- Myrowitz, Elliott H. “Juvenile Myopia Progression, Risk Factors and Interventions.” Saudi Journal of Ophthalmology. Elsevier, 13 Aug. 2015. Web. 17 Jan. 2016. <http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3729802/#b0075>.
- Feldkaemper M, Schaeffel F. An updated view on the role of dopamine in myopia. Exp Eye Res. 2013 Sep;114:106-19. doi: 10.1016/j.exer.2013.02.007. Epub 2013 Feb 19. PMID: 23434455.
- He M, Xiang F, Zeng Y, Mai J, Chen Q, Zhang J, Smith W, Rose K, Morgan IG. Effect of Time Spent Outdoors at School on the Development of Myopia Among Children in China: A Randomized Clinical Trial. JAMA. 2015 Sep 15;314(11):1142-8. doi: 10.1001/jama.2015.10803. PMID: 26372583.
- Wen L, Cao Y, Cheng Q, Li X, Pan L, Li L, Zhu H, Lan W, Yang Z. Objectively measured near work, outdoor exposure and myopia in children. Br J Ophthalmol. 2020 Nov;104(11):1542-1547. doi: 10.1136/bjophthalmol-2019-315258. Epub 2020 Feb 19. PMID: 32075819; PMCID: PMC7587221.
- Bullimore MA, Johnson LA. Overnight orthokeratology. Cont Lens Anterior Eye. 2020 Aug;43(4):322-332. doi: 10.1016/j.clae.2020.03.018. Epub 2020 Apr 22. PMID: 32331970.
- Ha A, Kim SJ, Shim SR, Kim YK, Jung JH. Efficacy and Safety of 8 Atropine Concentrations for Myopia Control in Children: A Network Meta-Analysis. Ophthalmology. 2022 Mar;129(3):322-333. doi: 10.1016/j.ophtha.2021.10.016. Epub 2021 Oct 22. PMID: 34688698.
- Chamberlain P, Peixoto-de-Matos SC, Logan NS, Ngo C, Jones D, Young G. A 3-year Randomized Clinical Trial of MiSight Lenses for Myopia Control. Optom Vis Sci. 2019 Aug;96(8):556-567. doi: 10.1097/OPX.0000000000001410. PMID: 31343513.
- Lam C.S.Y., Tang WC, Tse DY, Lee R.P.K., Chun R.K.M., Hasegawa K, et al. Defocus Incorporated Multiple Segments (DIMS) spectacle lenses slow myopia progression: a 2-year randomised clinical trial. Br J Ophthalmol. 2019.
- Cooper J, OʼConnor B, Watanabe R, Fuerst R, Berger S, Eisenberg N, Dillehay SM. Case Series Analysis of Myopic Progression Control With a Unique Extended Depth of Focus Multifocal Contact Lens. Eye Contact Lens. 2018 Sep;44(5):e16-e24. doi: 10.1097/ICL.0000000000000440. PMID: 29053555.
- JJV Data on file, 2021. Development of Optical Design of ACUVUE Abiliti 1-Day Soft Therapeutic Lenses for Myopia Management.
- Black K. Essilor’s Reveals Results of “Game-changing” Stellest Lens for Myopia https://www.mivision.com.au/2020/09/essilors-reveals-results-of-game-changing-stellest-lens-for-myopia/. mivision; 2020 [8/12/2020].
- Lane BC. Nutrition in Eye and Vision Development and Function. Santa Ana, California, USA: Optometric Extension Program Foundation, 1989, in press. Gardiner PA. Dietary treatment of myopia in children. Lancet 1958;1:1152-5. Kolosov VI, Kucheriavy NI, Kurochkin VN, et al. Further studies of the role of changes in phosphorocalcium metabolism in the mechanism of progression of myopia in children. Oftal’mologicheskii
- Eppenberger LS, Sturm V. The Role of Time Exposed to Outdoor Light for Myopia Prevalence and Progression: A Literature Review. Clin Ophthalmol. 2020 Jul 2;14:1875-1890. doi: 10.2147/OPTH.S245192. PMID: 32669834; PMCID: PMC7337435.
- Prieto-Garrido FL, Hernández Verdejo JL, Villa-Collar C, Ruiz-Pomeda A. Predicting factors for progression of the myopia in the MiSight assessment study Spain (MASS). J Optom. 2022 Jan-Mar;15(1):78-87. doi: 10.1016/j.optom.2020.11.003. Epub 2021 Mar 6. PMID: 33750678; PMCID: PMC8712588.