In 2022, the relevance of myopia management should come as no surprise to eyecare providers. Even prior to the COVID-19 pandemic, the increase in myopia prevalence was a global public health concern.¹ A recent report further underscored the impact of home confinement as it relates to myopia progression in school-aged children.² This rapidly increasing prevalence and resultant visual impairment, coupled with the robust and growing body of clinical evidence, supports the urgency of implementing a myopia management therapy for any level of myopia or pre-myopia.³ Understanding the significance of the myopia pandemic is critical. However, implementing myopia management into practice can feel overwhelming. Ultimately, providers will need to customize care for each child; but, by following the approach outlined below, they can gain a functional framework to begin managing myopia immediately.

STEP 1: ASSESSING RISK

Categorizing the myopia risk profile of a child can be a challenging task. Understanding the influence of genetics, ethnicity, lifestyle, the child’s age, refractive error, and axial length at diagnosis will help identify a child at risk for progressing myopia.

Eager for answers, parents often blame themselves for their child’s myopia. Although there are data supporting the influence of genetics, this role is not so straightforward. A child’s risk of developing myopia increases with one myopic parent and increases even more if both parents have myopia.⁴ However, twin studies have shown a variable hereditary contribution and may actually overestimate the heritability, as the studies do not account for shared environments. Family studies provide a more balanced perspective because of the shared familial environments.⁵

Studies have also shown a strong correlation between environmental influences and myopia.⁶ Over the years, our behavior as a global society has changed, transitioning toward more education, more urbanization, and more time indoors, all while worldwide myopia has continued to progress rapidly.⁷ Is this a coincidence? Observational studies have pointed toward a strong association between more years of education and an increase in myopia prevalence.^6-8 It is prudent to understand that these associations do not establish a cause-and-effect relationship. More recently, however, Mountjoy et al claimed to show a causal relationship between the number of years of education and the level of myopic refractive error.⁹

A causal relationship between increased time devoted to near work, specifically screen time, and worsening myopia has not been established.^10,11 Recent studies have suggested that the nature of near work may be key. Limiting close working distances (> 30cm) and taking breaks after 30 minute intervals can be beneficial against myopia.¹²

The protective role of time spent outdoors is well represented for myopia development but is less so for myopia progression.¹³ According to one study, children who spent more than two hours per day outdoors, even in the context of spending a large amount of time doing near work, decreased their risk of myopia.¹⁴ Why does spending time outdoors have a myopia control effect? It is not fully understood whether this is due to increased exposure to sunlight, varying intensities or wavelengths of light, or to the dynamic visual environment in an outdoor setting.^15-17

The baseline refractive error and age of a child at myopia diagnosis should play a significant role in establishing a risk profile. Providers should strongly consider treating every myopic child, particularly those who are myopic by age 9.¹⁸ Children who have ≤ +0.50D at age 7-to-8 years, ≤ +0.25D at age 9-to-10 years, and emmetropia at age 11 years show a significant risk for myopia development and progression.¹⁹ The younger that children develop myopia, particularly ≤ 7 years old, the faster their myopia will progress.²⁰

Another way to gauge the risk of myopia is to compare a child’s baseline axial length values to age-normal values. A comprehensive reference or normative values would be ideal; however, axial length growth charts have been published only for Chinese and European children at this time. These data indicate that Chinese children have longer axial lengths and that their axial length progresses faster compared to European children, even in normal emmetropic eye growth.^22,23 This underscores the role of ethnicity in risk analysis. Until growth charts for other patient populations become available, providers can use the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) data as a guideline for normal axial elongation during emmetropization: 0.1mm per year.¹⁹ If a child progresses more than this annually, consider a more significant myopia management strategy.

STEP 2: SELECT A MYOPIA MANAGEMENT THERAPY

Parents should be made aware that no myopia management therapy will permanently halt or reverse myopia and that most treatments are being used off-label. Informed consents addressing any potential side effects or risk of treatment should be provided in a written format.

Contact lenses should be the highest treatment consideration. They have benefits that go beyond vision correction and myopia control. Children wearing contact lenses have demonstrated higher self-esteem in areas of athletic competence, social acceptance, and physical appearance compared to children wearing glasses.²⁴

Soft Contact Lenses When possible, daily disposable soft contact lenses should be fit, as they can minimize the risk of adverse events in children.²⁵ Several studies now point to a high safety profile for longer-replacement modalities when appropriate contact lens hygiene is followed.²⁶

Multifocal soft contact lenses may be used as an off-label treatment for myopia control. Center-distance multizone designs with either concentric rings or aspheric plus power in the periphery of the lens provide clear distance vision. One dual-focus daily disposable soft lens is U.S. Food and Drug Administration-approved as a treatment indicated for slowing myopia progression.²⁷ Three-year study data for this lens show a significant slowing of refractive myopia progression that is reasonably consistent with slowing axial elongation.²⁸ The authors demonstrated similar effectiveness of the lenses over a six-year period.²⁹ When treatment was discontinued at seven years, the treatment effect was retained and did not rebound to offset any prior myopia control gains.³⁰ Another daily disposable option prescribed off-label for myopia control uses extended-depth-of-focus optics and has been reported to slow myopia progression.³¹ This lens design does offer a wide range of power parameters—up to –12.25D—which can be useful for higher myopes.

The Bifocal Lenses in Nearsighted Kids (BLINK) study confirms a dose-dependent myopia control effect with monthly replacement multifocal soft lenses, with a high add of +2.50D demonstrating a more significant reduction in the rate of myopia progression compared with a medium add power of +1.50D or with single-vision contact lenses.³²

Besides certification for certain lens brands, providers are not required to undergo much additional training to fit this lens type. Although pediatric contact lens fitting comes with challenges related to application and removal training and ensuring compliance, a motivated provider/parent combination is a force that can overcome these relatively small obstacles.

Orthokeratology Orthokeratology (ortho-k) lenses are worn overnight to reshape the cornea to temporarily correct myopia. Despite the fact that its use for myopia control is off-label, ortho-k tends to be a popular treatment option among families. The benefit of no daytime correction lends itself well to children’s often active schedules. Because the lenses are applied at bedtime and are worn during sleep, ortho-k gives parents more control over treatment implementation.

Ortho-k has a robust body of evidence supporting its use in slowing myopia progression:³³

• The Longitudinal Orthokeratology Research in Children study reported a slowing effect on myopia progression in children wearing ortho-k lenses over a 24-month period.³⁴
• The Retardation of Myopia in Orthokeratology study highlighted that younger children (ages 7-to-8 years) tend to have faster myopia progression and axial elongation,³⁵ suggesting a need for early clinical intervention in this age group. The study also reported that ortho-k wearers had a slower increase in axial elongation compared to those subjects wearing single-vision glasses.
• A five-year study demonstrated that children fit with ortho-k lenses showed less myopia progression during the first year versus the last three years of treatment,³⁶ implying a taper of myopia control effect after a certain period of time.
• Partial ortho-k proved to control myopia progression for higher amounts of myopia.³⁷
• Toric ortho-k lenses correcting up to –3.50D of with-the-rule astigmatism also showed effectivity in slowing myopia progression.³⁸

Additionally, ortho-k can be a safe treatment option provided that proper lens fitting, cleanliness protocols, and timely follow-up visits are established and followed.³⁹

Ortho-k uses a reverse geometry lens design, in which the back-optic-zone radius is fit flatter compared to the secondary curve. For cases of high or limbus-to-limbus corneal astigmatism, as evaluated on a corneal topography map (Figure 1), toric ortho-k lenses may be necessary.

Initial lens selection is based on spectacle prescription, keratometry, and the horizontal visible iris diameter. Corneal topography can be helpful in designing the initial lens and in troubleshooting abnormal fits, and it is essential for monitoring where the lens positions overnight.⁴⁰ The lens-to-cornea relationship is not the same in an open eye versus in a closed eye overnight. An ideal fitting pattern when viewed with slit lamp biomicroscopy (Figure 2) as well as with corneal topography maps after lens removal is a “bull’s eye” over the pupil, with resultant central flattening and midperipheral corneal steepening⁴⁰ (Figure 3). Following the initial lens dispense, evaluate children within the next 24 hours to rule out any complications such as corneal edema and lens binding. Make lens adjustments accordingly until the treatment lens is finalized.

 

There is no doubt that ortho-k fitting is more specialized and requires advanced training on a provider’s part. Due to the overnight wear schedule and the higher risk of complications, close monitoring is necessary for success with this treatment.

Atropine Atropine is a non-selective muscarinic acetylcholine receptor antagonist that is believed to target the retina, sclera, choroid, and retinal pigment epithelium to interfere with signals that promote myopia progression;⁴¹ however the exact mechanism of action for slowing myopia progression is not fully understood. The largest studies evaluating the effectiveness of atropine have been the Atropine in the Treatment of Myopia (ATOM) studies:

• ATOM1, with an interesting study design, used 1% atropine in one eye, while the other eye served as the control. The authors reported that 1% atropine was effective in demonstrating myopia control for both refractive and axial length, but it came with visual side effects.⁴²
• ATOM2 studied the safety and efficacy of lower doses of atropine concentrations (0.5%, 0.1%, and 0.01%). The results were profound in concluding that the 0.01% concentration of atropine was effective, with limited visual side effects.⁴³ ATOM2 also suggested that younger children, higher myopia at baseline, and those with two myopic parents may be poor responders to atropine.⁴⁴

The ATOM group is now studying the effects of 0.01% atropine for pre-myopes and for low myopia.⁴⁴

The Low-Concentration Atropine for Myopia Progression (LAMP) study highlighted a dose-dependent response to three concentrations of atropine.⁴⁵ The phase 2 report concluded that the efficacy of 0.05% atropine was double that of 0.01% atropine and that 0.05% remained the optimal concentration for myopia control.⁴⁶

Low-dose atropine is a popular choice for children when contact lenses are not a good option. A single drop in each eye is prescribed prior to bedtime. Although rare, side effects may include blurred near vision, difficulty focusing at near, or photophobia. Photochromic lenses, bifocals, or progressive addition lenses (PALs) may be recommended to combat these concerns. Preservative-free atropine of varying concentrations can be prescribed but requires a compounding pharmacy.

Combination therapy with atropine and ortho-k may represent an option for even more effective myopia control than with either single therapy alone.⁴⁷ From the limited volume of data currently available on combination therapy, these points are worth considering:

• The enhanced effect of combined therapy topped off at six months. After this period, both the combination group and the ortho-k-only group showed no significant difference in myopia progression.⁴⁸
• The group using combined therapy had pupils that measured 0.3mm larger compared with the group using ortho-k only at one year.⁴⁸ Does this enlarged pupil size play a role in enhancing myopia control? Chen et al also found a stronger myopia control effect for larger pupil sizes.⁴⁹
• A two-year prospective study reported a significant myopia control effect for the children who had 1.00D to 3.00D of myopia but not for the children who had 3.00D to 6.00D of myopia.⁵⁰ Could this suggest that atropine should be used only for children who have low myopia?

The Bifocal and Atropine Myopia Control (BAM) study is currently investigating the combined effect of 0.01% atropine and soft multifocal center-distance lenses on myopia progression.⁵¹ This will be the first prospective study based in the United States, all others have studied children in East Asia.

Spectacles Although not practiced today, under-correcting myopia was once considered an appropriate form of myopia control.⁵² Bifocal spectacles and PALs have been used for many decades in attempts to control myopia. The Correction of Myopia Evaluation Trial (COMET) demonstrated a statistically significant, yet clinically insignificant, difference in myopia progression for those children wearing PALs compared with single-vision lenses.⁵³ Interestingly, the benefit of the myopia control diminished after six-to-12 months of treatment.⁵³ PALs and executive bifocals have been beneficial in reducing myopia progression for those children who have large lags of accommodation or esodeviation at near,^53,54 supporting the notion that some children who have specific binocular vision conditions may benefit from spectacles for myopia control.

Having access to effective and easy-to-prescribe spectacle designs will revolutionize myopia management. Although not available in the United States today, newer generations of spectacle lens designs are on the horizon:

• The Defocus Incorporated Multiple Segments (DIMS) design provides central distance vision with an annular area that encompasses hundreds of smaller add power segments in the midperiphery. This study reported reduced myopia progression and slowing of axial elongation compared with single-vision spectacle use over a two-year period,⁵⁵ with sustained results in the three-year follow-up.⁵⁶
• Highly Aspheric Lenslet Target (HALT) technology uses a central distance area with peripheral aspheric lenslets. The one-year data suggest a dose-dependent effect.⁵⁷
• In the final stages of research and development is the Diffusion Optics Technology (DOT), which has a clear distance zone with peripheral light scatter of varying size and shape. The one-year data shows promising results of high refractive and axial length myopia control.⁵⁸

For most practitioners who practice myopia management in the United States, the first line of optical treatment is contact lenses; however spectacles have an important role in myopia management. Children primarily treated with atropine will still need vision correction, and bifocal spectacles or PALs may be a good option. In the context of binocular vision concerns, bifocal spectacles can be used to alleviate symptoms while simultaneously slowing myopia progression. Lastly, children using daytime soft contact lenses will need a backup pair of spectacles.

Providers should never neglect to couple an optical or pharmacological treatment with strong lifestyle modification recommendations. Figure 4 (courtesy of Dr. Fuensanta Vera-Diaz) shows an example of a written handout with research-based recommendations that can be shared with families.

The myopia treatment selected should include consideration of functional (e.g., binocular vision status) and anatomical (e.g., pupil size, refractive error, corneal topography, axial length) ocular differences as well as the families’ lifestyle and level of motivation for the treatment.

STEP 3: MANAGE MYOPIA PROGRESSION

Adapted from the International Myopia Institute (IMI) Clinical Management Guidelines,⁵⁹ Table 1 summarizes recommendations for management schedules based on the treatment type selected. Regardless of the chosen treatment, children should be monitored every six months thereafter for efficacy, compliance, and safety.

Wearing time may affect visual acuity and treatment efficacy. Multifocal soft contact lenses should be worn between five-to-eight hours per day.⁶⁰ Ortho-k lenses should be worn for a minimum of eight hours per night to ensure adequate full-day vision.⁴⁰

A change or discontinuation of a treatment may be warranted due to concerns with safety or efficacy. A switch to another treatment or to a combination treatment for an additive effect should be considered first; however cessation may be necessary for safety concerns. When should you cease an effective treatment? Myopia stability should be the top consideration. According to the COMET study, 95% of children who have myopia will stabilize by 24 years of age.⁵³

Measuring axial length is a basis for evaluating treatment efficacy in research studies. Clinicians may find it valuable for decision making and for gauging success with a chosen treatment. It is difficult to monitor refractive changes in ortho-k without a full washout from lens wear, and over-refractions may be unreliable if the lens is warped. If a provider is monitoring myopia progression using refractive status only, it is important to understand that the relationship between axial length and refraction measurements is not straightforward and may not correlate consistently for children of all ages.²⁸ Also, there has been a mismatch between refractive and axial myopia control in atropine studies.⁴⁶ The true concern with myopia progression is the elongation of the eye, so it seems appropriate to measure the length of the eye to evaluate risk of disease progression.^61,62 Absolute measures of axial length can serve as a key risk indicator, and relative measures are important in gauging success. The IMI recognizes the complex and sometimes unreliable diagnostic measurement of axial length in clinical practice.⁵⁹ As providers learn more about what normal and accelerated eye growth looks like for each patient based on their individual risk profile, a measurement of axial length will likely become a standard of care for a myopia management practice.

With the combined determination and dedication of clinicians and academics, the many unknowns surrounding myopia management are beginning to unfold. Until formal guidelines are established, evidence-based data should continue to drive clinical decision making in myopia management practice. CLS

REFERENCES

1. Holden BA, Fricke TR, Wilson DA, et al. Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 2050. Ophthalmology. 2016 May;123:1036-1042.
2. Wang J, Li Y, Musch DC, et al. Progression of Myopia in School-Aged Children after COVID-19 Home Confinement. JAMA Ophthalmol. 2021 Mar 1;139:293-300.
3. Fang P-C, Chung M-Y, Yu H-J, Wu P-C. Prevention of myopia onset with 0.025% atropine in premyopic children. J Ocul Pharmacol Ther. 2010 Aug;26:341-345.
4. Zhang X, Qu X, Zhou X. Association between parental myopia and the risk of myopia in a child. Exp Ther Med. 2015 Jun;9:2420-2428.
5. Sanfilippo PG, Hewitt AW, Hammond CJ, Mackey DA. The heritability of ocular traits. Surv Ophthalmol. 2010 Nov-Dec;55:561-583.
6. Rose KA, French AN, Morgan IG. Environmental Factors and Myopia: Paradoxes and Prospects for Prevention. Asia Pac J Ophthalmol (Phila). 2016 Nov/Dec;5:403-410.
7. Dolgin E. The myopia boom. Nature. 2015 Mar 19;519:276-278.
8. Harman NB. The Education of High Myopes. Proc R Soc Med. 1913;6(Sect Ophthalmol):146-163.
9. Mountjoy E, Davies NM, Plotnikov D, et al. Education and myopia: assessing the direction of causality by mendelian randomisation. BMJ. 2018 Jun 6;361:k2022.
10. Gajjar S, Ostrin LA. A systematic review of near work and myopia: measurement, relationships, mechanisms and clinical corollaries. Acta Ophthalmol. 2021 Oct 7. [Epub ahead of print]
11. Lanca C, Saw SM. The association between digital screen time and myopia: A systematic review. Ophthalmic Physiol Opt. 2020 Mar;40:216-229.
12. Huang P-C, Hsiao Y-C, Tsai C-Y, et al. Protective behaviours of near work and time outdoors in myopia prevalence and progression in myopic children: a 2-year prospective population study. Br J Ophthalmol. 2020 Jul;104:956-961.
13. Deng L, Pang Y. Effect of Outdoor Activities in Myopia Control: Meta-analysis of Clinical Studies. Optom Vis Sci. 2019 Apr;96:276-282.
14. Rose KA, Morgan IG, Ip J, et al. Outdoor activity reduces the prevalence of myopia in children. Ophthalmology. 2008 Aug;115:1279-1285.
15. Ngo C, Saw SM, Dharani R, Flitcroft I. Does sunlight (bright lights) explain the protective effects of outdoor activity against myopia? Ophthalmic Physiol Opt. 2013 May;33:368-372.
16. Hua W-J, Jin J-X, Wu X-Y, et al. Elevated light levels in schools have a protective effect on myopia. Ophthalmic Physiol Opt. 2015 May;35:252-262.
17. Flitcroft DI. The complex interactions of retinal, optical and environmental factors in myopia aetiology. Prog Retin Eye Res. 2012 Nov;31:622-660.
18. Gifford K. Assessing Risk of Myopia Onset and Progression. Myopia Profile. 2019 Aug 2. Available at https://www.myopiaprofile.com/assessing-risk-of-myopia-onset-and-progression . Accessed Oct. 6, 2021.
19. Zadnik K, Sinnott LT, Cotter SA, et al. Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study Group. Prediction of Juvenile-Onset Myopia. JAMA Ophthalmol. 2015 Jun;133:683-689.
20. Chua SY, Sabanayagam C, Cheung YB, Chia A, et al. Age of onset of myopia predicts risk of high myopia in later childhood in myopic Singapore children. Ophthalmic Physiol Opt. 2016 Jul;36:388-394.
21. Klaver C, Polling JR; Erasmus Myopia Research Group. Myopia management in the Netherlands. Ophthalmic Physiol Opt. 2020 Mar;40:230-240.
22. Tideman JWL, Polling JR, Vingerling JR, et al. Axial length growth and the risk of developing myopia in European children. Acta Ophthalmol. 2018 May;96:301-309.
23. Sanz Diez P, Yang L-H, Lu M-X, Wahl S, Ohlendorf A. Growth curves of myopia-related parameters to clinically monitor the refractive development in Chinese schoolchildren. Graefes Arch Clin Exp Ophthalmol. 2019 May;257:1045-1053.
24. Walline JJ, Jones LA, Sinnott L, et al; ACHIEVE Study Group. Randomized trial of the effect of contact lens wear on self-perception in children. Optom Vis Sci. 2009 Mar;86:222-232.
25. Woods J, Jones D, Jones L, et al. Ocular health of children wearing daily disposable contact lenses over a 6-year period. Cont Lens Anterior Eye. 2021 Aug;44:101391.
26. Bullimore MA. The Safety of Soft Contact Lenses in Children. Optom Vis Sci. 2017 Jun;94:638-646.
27. U.S. Food and Drug Administration. FDA approves first contact lens indicated to slow the progression of nearsightedness in children. Available at https://www.fda.gov/news-events/press-announcements/fda-approves-first-contact-lens-indicated-slow-progression-nearsightedness-children . Accessed Sept. 21, 2021.
28. 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;96:556-567.
29. Chamberlain P, Peixoto-de-Matos SC, Arumugam B. Jones D, et al. Myopia Progression in Children wearing Dual-Focus Contact Lenses: 6-year findings. Poster presented at the virtual American Academy of Optometry meeting, October 2020; 200038.
30. Chamberlain P, Arumugam B, Jones D, et al. Myopia Progression on Cessation of Dual-Focus Contact Lens Wear: MiSight 1 day 7-Year Findings. Optom Vis Sci. 2021;98:E-abstract 210049.
31. Sankaridurg P, Bakaraju RC, Naduvilath T, et al. Myopia control with novel central and peripheral plus contact lenses and extended depth of focus contact lenses: 2 year results from a randomised clinical trial. Ophthalmic Physiol Opt. 2019 Jul;39:294-307.
32. Walline JJ, Walker MK, Mutti DO, et al. Effect of High Add Power, Medium Add Power, or Single-Vision Contact Lenses on Myopia Progression in Children: The BLINK Randomized Clinical Trial. JAMA. 2020 Aug 11;324:571-580.
33. VanderVeen DK, Kraker RT, Pineles SL, et al. Use of Orthokeratology for the Prevention of Myopic Progression in Children: A Report by the American Academy of Ophthalmology. Ophthalmology. 2019 Apr;126:623-636.
34. Cho P, Cheung SW, Edwards M. The longitudinal orthokeratology research in children (LORIC) in Hong Kong: a pilot study on refractive changes and myopic control. Curr Eye Res. 2005 Jan;30:71-80.
35. Cho P, Cheung SW. Retardation of myopia in Orthokeratology (ROMIO) study: a 2-year randomized clinical trial. Invest Ophthalmol Vis Sci. 2012 Oct 11;53:7077-7085.
36. Hiraoka T, Kakita T, Okamoto F, Takahashi H, Oshika T. Long-term effect of overnight orthokeratology on axial length elongation in childhood myopia: a 5- year follow-up study. Invest Ophthalmol Vis Sci. 2012 Jun 22;53:3913-3919.
37. Charm J, Cho P. High myopia-partial reduction ortho-k: a 2-year randomized study. Optom Vis Sci. 2013 Jun;90:530-539.
38. Chen C, Cheung SW, Cho P. Myopia control using toric orthokeratology (TO-SEE study). Invest Ophthalmol Vis Sci. 2013 Oct 3;54:6510-6517.
39. Liu YM, Xie P. The Safety of Orthokeratology--A Systematic Review. Eye Contact Lens. 2016 Jan;42:35-42.
40. Vincent SJ, Cho P, Chan KY, et al. CLEAR - Orthokeratology. Cont Lens Anterior Eye. 2021 Apr;442:240-269.
41. Upadhyay A, Beuerman RW. Biological Mechanisms of Atropine Control of Myopia. Eye Contact Lens. 2020 May;46:129-135.
42. Chua W, Balakrishnan V, Tan D, Chan Y; ATOM Study Group. Efficacy Results from the Atropine in the Treatment of Myopia (ATOM) Study. Invest Ophthalmol Vis Sci. 2003 May;44:3119.
43. Chia A, Chua W-H, Cheung Y-B, et al. Atropine for the treatment of childhood myopia: safety and efficacy of 0.5%, 0.1%, and 0.01% doses (Atropine for the Treatment of Myopia 2). Ophthalmology. 2012 Feb;119:347-354.
44. HealthXChange.sg. New Atom 3 Myopia Study Aims To Prevent The Onset Of Myopia In Young Children Even Before It Starts, Or Control It Just When It Is Starting. Press Release. Available https://www.healthxchange.sg/news/new-atom-3-myopia-study-aims-to-prevent-the-onset-of-myopia-in-young-children-even-before-it-starts-or-control-it-just-when-it-is-starting . Accessed Feb. 4, 2022.
45. Yam JC, Jiang Y, Tang SM, et al. 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. 2019 Jan;126:113-124.
46. Yam JC, Li FF, Zhang X, et al. Two-Year Clinical Trial of the Low-Concentration Atropine for Myopia Progression (LAMP) Study: Phase 2 Report. Ophthalmology. 2020 Jul;127:910-919.
47. Gao C, Wan S, Zhang Y, Han J. The Efficacy of Atropine Combined With Orthokeratology in Slowing Axial Elongation of Myopia Children: A Meta-Analysis. Eye Contact Lens. 2021 Feb 1;47:98-103.
48. Tan Q, Ng AL, Choy BN, Cheng GP, Woo VC, Cho P. One-year results of 0.01% atropine with orthokeratology (AOK) study: a randomised clinical trial. Ophthalmic Physiol Opt. 2020 Sep;40:557-566.
49. Chen Z, Niu L, Xue F, et al. Impact of pupil diameter on axial growth in orthokeratology. Optom Vis Sci. 2012 Nov;89:1636-1640.
50. Kinoshita N, Konno Y, Hamada N, et al. Efficacy of combined orthokeratology and 0.01% atropine solution for slowing axial elongation in children with myopia: a 2-year randomised trial. Sci Rep. 2020 Jul 29;10:12750.
51. Huang J, Mutti DO, Jones-Jordan LA, Walline JJ. Bifocal & Atropine in Myopia Study: Baseline Data and Methods. Optom Vis Sci. 2019 May;96:335-344.
52. Chung K, Mohidin N, O’Leary DJ. Undercorrection of myopia enhances rather than inhibits myopia progression. Vision Res. 2002 Oct;42:2555-2559.
53. Gwiazda J, Hyman L, Hussein M, et al. A randomized clinical trial of progressive addition lenses versus single vision lenses on the progression of myopia in children. Invest Ophthalmol Vis Sci. 2003 Apr;44:1492-1500.
54. Cheng D, Woo GC, Drobe B, Schmid KL. Effect of bifocal and prismatic bifocal spectacles on myopia progression in children: three-year results of a randomized clinical trial. JAMA Ophthalmol. 2014 Mar;132:258-264.
55. Lam CSY, Tang WC, Tse DY, et al. Defocus Incorporated Multiple Segments (DIMS) spectacle lenses slow myopia progression: a 2-year randomised clinical trial. Br J Ophthalmol. 2020 Mar;104:363-368.
56. Lam CS, Tang WC, Lee PH, et al. Myopia control effect of defocus incorporated multiple segments (DIMS) spectacle lens in Chinese children: results of a 3-year follow-up study. Br J Ophthalmol. 2021 Mar 17:bjophthalmol-2020-317664. [Epub ahead of print]
57. Bao J, Huang Y Li X, et al, Myopia control with spectacle lenses with aspherical lenslets: a 2-year randomized clinical trial. Invest Ophthalmol Vis Sci. 2021 Jun;62:2888.
58. Rappon J, Neitz J, Neitz M. Novel DOT Lenses from Sightglass Vision Show Great Promise to Fight Myopia. Review of Myopia Management. 2020 Apr 21. Available at https://reviewofmm.com/novel-dot-lenses-from-sightglass-vision-show-great-promise-to-fight-myopia/ . Accessed Feb. 4, 2022.
59. Gifford KL, Richdale K, Kang P, et al. IMI - Clinical Management Guidelines Report. Invest Ophthalmol Vis Sci. 2019 Feb 28;60:M184-M203
60. Lam CSY, Tang WC, Tse DY, Tang YY, To CH. Defocus Incorporated Soft Contact (DISC) lens slows myopia progression in Hong Kong Chinese schoolchildren: a 2-year randomised clinical trial. Br J Ophthalmol. 2014 Jan;98:40-45.
61. Haarman AEG, Enthoven CA, Tideman JWL, Tedja MS, Verhoeven VJM, Klaver CCW. The Complications of Myopia: A Review and Meta-Analysis. Invest Ophthalmol Vis Sci. 2020 Apr 9;61:49.
62. Tideman JWL, Snabel MCC, Tedja MS, et al. Association of Axial Length With Risk of Uncorrectable Visual Impairment for Europeans With Myopia. JAMA Ophthalmol. 2016 Dec 1;134:1355-1363.