m
Recent Posts
Connect with:
Thursday / May 26.
HomemistoryMyopia Management: Practising with the Latest Evidence-base

Myopia Management: Practising with the Latest Evidence-base

Myopia management is a fast-moving field of science, requiring clinicians to keep pace with the evidence-base on treatments, pathology and more. The best-practice treatments to slow childhood myopia progression are evolving as research and industry innovations grow. The good news, though, is that the latest research, comparing treatments and articulating benefits, is making clinical myopia management simpler.

This article compares treatments using current evidence, including combining treatments with atropine; discusses clinical communication – how to explain myopia control efficacy and benefits at the outset; and describes how to gauge the success of treatments over time.

WHICH MYOPIA CONTROL TREATMENT WORKS BEST?

The biggest shift in understanding myopia control efficacy has been to move from comparing percentages to comparing absolute treatment effects. This is because the control group can heavily influence percentage outcomes. For example, a younger group can lead to a lower percentage efficacy, simply because younger children progress more quickly.1,2

Adding atropine to orthokeratology appears to increase efficacy by 0.09mm over one year. The ideal concentration is likely 0.01% and the ideal targets may be lower myopes

Figure 1. Efficacy comparison of myopia control treatments, based on two percentage categories, as described in the text. Optical interventions are on the left and comparison to current data on atropine concentration is on the right. Image
© Myopia Profile Pty Ltd 2021, from the online course Communicating the Myopia Message, used under limited license.

Study duration is also a factor, with shorter studies tending to show a larger percentage effect. Recent analysis across multiple treatments has found an ‘initial burst of efficacy’, with up to 40% of the cumulative multi-year total occurring in the first six months, and around 50% occurring within the first year.3 Does this mean we should change treatments every six to twelve months to maximise efficacy? Not necessarily – the reduction in absolute treatment with time could reflect the slowing of myopia progression with age, or an adaptation to the mechanism of the treatment. What this does indicate is that it is erroneous to extrapolate a percentage treatment for any duration longer than that of the specific study on that intervention.

This may seem complex but it actually makes clinical decision making and communication easier. Instead of percentages, analysis has moved to comparing the absolute effects. In one of the most notable myopia papers published in the last year, Noel Brennan and colleagues3 analysed the Cumulative Absolute Reduction in axial Elongation (CARE) and concluded that “no single method of treatment shows clear superiority, with the best of orthokeratology, soft multifocal contact lenses (SMCLs), spectacles and atropine showing similar effect”. The authors then explained the following caveats:

  • Some treatments within these categories (e.g. “SMCLs that prioritise clear vision, progressive addition spectacles and 0.01% atropine”) may be less effective,
  • Side effects and potential for rebound within these categories may influence success, and
  • The clinician should factor in their own skill set, treatment availability, patient and parent preferences and capacity, and regulatory considerations in choosing the ideal treatment.

The clinical message here is to pick the treatment you have available to you, that suits the patient and their family. Based on our current understanding, numerous options appear to work similarly to control myopia; these being dual-focus soft contact lenses,4 orthokeratology (OK),5 the newest myopia controlling spectacles (DIMS and H.A.L.T. technology)6,7 and 0.05% atropine.8 Results for slowing axial elongation, which provide far more accurate scientific results than refraction,9 show that every clinician has multiple, similarly effective options available to them for myopia control.

Figure 2. Average annual refractive myopia progression for children corrected with single vision spectacles. Image © Myopia Profile Pty Ltd 2021, from the online course Communicating the Myopia Message, used under limited license.

ADDING ATROPINE

There are currently four studies of 12-24 months duration, on combining atropine with OK: two retrospective involving varied concentrations and two prospective which investigate 0.01% atropine. A 2021 metaanalysis10 investigated the retrospective studies with other short-term randomised controlled trials and found a statistically significant reduction in axial elongation of 0.09mm over one year in combination treatment compared to OK alone.

The two newest, prospective randomised controlled trials11,12 have shown the same outcomes, with more information on the ideal targets and timescale of the effect.

  • Tan et al11 found 0.09mm more reduction in axial elongation over 12 months in 1-4D myopes, with the stronger combined effect found in the first six months only,
  • Kinoshita et al12 found 0.18mm more reduction in axial elongation over 24 months in 1-3D myopes, with the stronger combined effect found in the first 12 months only. There was no effect of adding atropine 0.01% to 3-6D myopes, but this group progressed slower overall than the lower myopes.

The summary of this is that adding atropine to OK appears to increase myopia control efficacy by 0.09mm over one year or 0.18mm over two years. The ideal concentration is likely 0.01% and the ideal targets may be lower myopes, with the effects likely being short-term.

There is currently no other data on combining atropine with optical treatments, although a study on atropine 0.01% with centre-distance +2.50 Add SMCL is underway. Only baseline and favourable short-term tolerance data has thus far been reported.13

CLINICAL COMMUNICATION: BENEFITS AND EFFICACY

When communicating the ‘why’ of myopia control, it is important to consider both the short-term and long-term benefits. As clinicians, the long-term message that there is no safe level of myopia, with each dioptre increasing the risk of lifelong pathology and vision-impairment,14 provides a clear motivation for the preventative benefits of myopia control. Two new analyses of risk-to-benefits compare the short-term risks of contact lens infection with the long-term risks of myopia-associated pathology and vision impairment, with the following findings.

Pick the treatment you have available to you, that suits the patient and their family… numerous options appear to work similarly to control myopia

Long-term Benefits 

Firstly, the comparative lifetime risks of contact lens wear commenced at age eight for myopia control, and continued throughout life until age 65, are relatively less than the lifetime risks of vision impairment from myopia-associated pathology when myopia is over 3D or axial length is in excess of 26mm. When only childhood CL wear is considered, the risk comparison is clearly skewed towards the positive impact of CL wear, especially in daily disposable CL wear.15 

Secondly, for an individual, each additional dioptre of myopia is associated with a 58%, 20%, 21%, and 30% increase in the risk of myopic maculopathy, open-angle glaucoma, posterior subcapsular cataract, and retinal detachment, respectively. Modelling indicated that a 3D myope is predicted to experience 4.4 years and, for an 8D myope, 9.6 years of visual impairment. When considering five years of myopia controlling contact lens wear, every one person treated will be saved around one year of vision impairment, on average. By comparison, fewer than one in 38 will experience a loss of vision as a result of myopia control based on estimates.16

These facts and figures provide the clear foundation for the long-term benefits of myopia control. These statements may ring true with parents, or may in fact be difficult for parents to grasp, especially if they have no experience of myopia, ocular disease or vision impairment themselves.17 Instead, the short-term benefits may gain more traction in communication with parents.

Short-term Benefits 

Understanding a concept called ‘temporal myopia’ is important here. Temporal myopia is a psychological phenomenon – a reticence to consider the long-term outcomes of an action when making a choice. Decisions often involve a time factor, and typically we tend to prioritise the present and minimise the value of the future gain or loss from the choice.18 What this can mean in myopia management is that a parent may show better understanding of the short-term gains of commencing myopia control, after which the long-term gains can be framed as an additional benefit.

Figure 3. Average annual projected refractive myopia progression for children prescribed a treatment from the ‘best’ category. Image © Myopia Profile Pty Ltd 2021, from the online course Communicating the Myopia Message,
used under limited license.

The short-term benefits of myopia control are the slower progression of refractive change. For example, an eight-year-old child in a single vision correction will progress by around one dioptre in a year.2 If that child goes one year between eye exams, he or she could potentially be spending half of that time with clear distance vision, and half with blur due to progression. With myopia control, that clear-vision-time between eye exams is extended – the eight-year-old spends minimal or even no time suffering blurred vision between eye exams, even more so if the six-monthly eye exams recommended by the International Myopia Institute Clinical Management Guidelines are followed.19

A parent may show better understanding of the short-term gains of myopia control, after which long-term gains can be framed as an additional benefit

DESCRIBING EFFICACY

As described above, percentage efficacy, expressed in a single study, indicates how well a treatment works compared to a control group. However, it can’t be directly compared between studies as the duration of the study, age and even ethnicity of participants can all influence the percentage.

Percentages can be useful, though, in communicating with parents. Explaining that the best class of treatments slow progression by ‘around half ’ or ‘50%’ communicates that we can’t promise to stop myopia progression, and also helps to set short-term goals for treatment, in line with the duration of the studies. This is based on the evidence-base of dual-focus soft contact lenses,4 OK,5 the newest myopia controlling spectacles,6,7 and 0.05% atropine,8 all slowing axial elongation growth over the duration of their specific studies by around half. OK rates a special mention as the intervention with the largest volume of data, with meta-analyses showing a consistent, robust myopia control effect over several studies with differing settings and participant populations.20

On MyopiaProfile.com, the freely available Myopia Management Guidelines Infographics use these categories for describing efficacy, to help set parental expectations for treatment.

The ‘50%’ category of treatments are the best available options. Based on their studies, myopia progression can be expected to slow by about half, over one to three years’ treatment duration. The next-best options slow progression by ‘about a third’, with axial length control outcomes of around 33% in their specific studies. These ‘next-best’ options include bifocal and prismatic bifocal spectacles,21 extended depth-of-focus22 and continuous aspheric centre-distance multifocal contact lenses,23 and 0.025% atropine.8 The less effective treatments include peripheral defocus spectacles,24 progressive addition spectacles25 and 0.01% atropine,8 based on current data. Figure 1 shows this comparison, with the ‘gold star’ awarded to OK for the reason described.

GAUGING SUCCESS

After setting expectations and commencing a myopia control treatment plan, how can we tell if the treatment is working? Using data on typical, single-vision corrected progression in myopic children, we can gauge success over one year based on refraction, using the percentage treatment ‘categories’ as described above. The free-to-download Myopia Profile Managing Myopia Guidelines Infographics provide support to do this, with Figures 2 and 3 providing an example. The latest recommendations are to judge treatment success after a minimum of one year, to account for potential seasonal variation in myopia progression.3

Figure 4. The average observed axial elongation per year for emmetropes and myopes, based on their age. Image © Myopia Profile Pty Ltd 2021, from the clinical article How Much Axial Length Growth Is Normal, used under limited license.

Figure 2 shows the amount of myopia progression per year for a child, corrected with single vision distance spectacles, based on meta-analysis data.2 This could be considered the ‘no treatment’ scenario, with 0% efficacy to slow progression. Figure 3 shows this annual progression reduced by half, for the ‘50%’ category of treatments as previously described. If a child progresses by less than, or equivalent to this annual amount, this can be considered a good outcome. If the child progresses by close to the single-vision amount, then the treatment is not working as expected. Modifiable factors influencing treatment success can include compliance, wearing time and user error, so these should be investigated with the patient and parents. Visual environment should also be discussed with all myopic children – managing the near work environment with appropriate working distances and regular breaks, plus decreasing leisure screen time and increasing outdoor time as much as possible.19

When using this method to gauge success of myopia management, consideration must be given to achieving the most accurate refraction possible, either by cycloplegia19 or using fogging techniques with retinoscopy, subjective refraction or open-field autorefraction. Using these latter techniques render results typically within 0.25D of a cycloplegic result.26,27 When using axial length to gauge success, optical biometry techniques are the most accurate, being around seven times more accurate to detect small changes than refraction. By comparison, ultrasound techniques are no more accurate than refraction.9

Using absolute measures, and comparing from visit-to-visit, myopia control success can again be gauged in reference to the ‘untreated’ progression and expected impact of the treatment. Figure 4 shows a summary of available research on how much axial length growth is typically observed in emmetropes (as a normal process of emmetropisation) and in untreated myopes wearing single vision distance correction.28-32 So, what does myopia control success look like?

  • For children under age 10, early onset and faster progression of myopia puts them at greater risk of high myopia.1 If ‘untreated’ myopia progression is typically greater than 0.3mm per year, then slowing annual progression to less than this is the ideal outcome. Since emmetropes of that same age progress by 0.1-0.2mm per year, slowing progression to this rate is an excellent outcome.
  • For pre-teen and teenage progressing myopes, slowing their axial elongation to less than the ‘untreated’ average of 0.2mm per year is an ideal outcome. Slowing to less than 0.1mm per year is an excellent outcome, considering that emmetropes of the same age show axial elongation of around this amount, ceasing typically by age 12 to 13.

Many of the latest instruments, designed specifically to measure axial length for myopia management, incorporate additional functionality such as auto-refraction and keratometry (the Oculus Myopia Master) or topography and pupillometry (Topcon Myah). Additionally, they include axial length growth charts to support gauging progress and reporting success. These axial length percentile growth charts provide an individualised approach, rather than gauging a child’s outcomes against an average. They allow a child’s axial length to be compared against their peers to set the proactivity of treatment goals and, as such, treatment success is determined by a reduction in their percentile rank over time.33

The latest recommendations are to judge treatment success after one year, to account for potential seasonal variation in myopia progression

Scientists are still seeking to understand how many percentile ranks indicate treatment success, with only one research abstract so far superimposing the MiSight dual-focus contact lens three-year clinical study data4 on a percentile chart. The findings were that the control group tracked along their mean centile with minimal change over three years – they didn’t progress faster or slower compared to average. By comparison, the MiSight wearing children reduced by a mean of 10.7 centile points.34 Perhaps this indicates a reasonable target for the ‘best’ category of treatments – time, and more science, will tell.

As practitioners, we should measure treatment outcomes over a year to account for seasonal variation in myopia progression, and review the patient every six months; at those interim appointments, assessing suitability, compliance and vision/eye health outcomes.3,19

WHAT TO DO IN PRACTICE

In April 2021, the World Council of Optometry made a unanimous resolution that myopia management must be adopted as a standard of optometric care.35 This was defined as:

  • Mitigation: attempting to prevent or delay onset of myopia by providing advice on the visual environment and watching for pre-myopia,
  • Measurement: providing regular comprehensive vision and eye health examinations for myopic children, including measuring refraction and axial length where possible, and
  • Management: addressing patients’ needs today to correct and control myopia with evidence-based interventions.

This means that we each now have an imperative to discuss myopia risk factors and the visual environment, identify children at risk of myopia, undertake regular eye exams (advised every six months by the International Myopia Institute)19 and offer myopia correction and control. It makes sense to consider our optical treatments (spectacles and contact lenses) as first line for myopia management as they both correct myopia and slow its progression.

we each now have an imperative to discuss myopia risk factors and the visual environment, identify children at risk of myopia, undertake regular eye exams… and offer myopia correction and control

Myopia management offers the opportunity to deliver better care and clearer vision to our young patients, while also optimising their chances for improved lifelong eye health and vision outcomes. Additionally, it is an unparalleled opportunity for professional growth and challenge, engagement with the leading scientific edge of eye care, and building expertise. While it involves interdisciplinary care and awareness, myopia management starts with optometry. There are numerous educational and clinical resources available to support this process – the time to get started is now.

To earn your CPD hours from this article, visit mieducation.com/myopia-management-practisingwith- the-latest-evidence-base. 

Dr Kate Gifford, PhD, BAppSc(Optom)Hons, FAAO is a clinician-scientist and peer educator in private practice in Brisbane. She holds four professional fellowships, over 80 peer reviewed and professional publications, and has presented over 160 conference lectures around the world, primarily on clinical myopia management. Dr Gifford is the Chair of the Clinical Management Guidelines committee of the International Myopia Institute and lead author on their report. She is a co-founder and director of the education platform Myopia Profile. 

References 

  1. Chua SY, Sabanayagam C, Cheung YB et al. Age of Onset of Myopia Predicts Risk of High Myopia in Later Childhood in Myopic Singapore Children. Ophthal Physiol Opt 2016;36:388-94. 
  2. Donovan L, Sankaridurg P, Ho A et al. Myopia Progression Rates in Urban Children Wearing Single-Vision Spectacles. Optom Vis Sci 2012;89:27-32. 

3. Brennan NA, Toubouti YM, Cheng X, Bullimore MA. Efficacy in myopia control. Prog Retin Eye Res. 2020 Nov 27:100923. 

  1. 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 
  2. Sun Y, Xu F, Zhang T, Liu M, Wang D, Chen Y, Liu Q. Orthokeratology to control myopia progression: a metaanalysis. PLoS One. 2015 Apr 9;10(4):e0124535. 
  3. Lam CSY, Tang WC, Tse DY, Lee RPK, Chun RKM, Hasegawa K, Qi H, Hatanaka T, To CH. Defocus Incorporated Multiple Segments (DIMS) spectacle lenses slow myopia progression: a 2-year randomised clinical trial. Br J Ophthalmol. 2020 Mar;104(3):363-368. doi: 10.1136/bjophthalmol-2018-313739. 
  4. 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. 2021:318367. 
  5. Yam JC, Jiang Y, Tang SM, Law AKP, Chan JJ, Wong E, Ko ST, Young AL, Tham CC, Chen LJ, Pang CP. 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(1):113-124. 
  6. Wolffsohn JS, Kollbaum PS, Berntsen DA, Atchison DA, Benavente A, Bradley A, Buckhurst H, Collins M, Fujikado T, Hiraoka T, Hirota M, Jones D, Logan NS, Lundstrom L, Torii H, Read SA, Naidoo K. IMI – Clinical Myopia Control Trials and Instrumentation Report. Invest Ophthalmol Vis Sci. 2019;60(3):M132-M160. 
  7. 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(2):98-103. 
  8. 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 and Physiological Optics. 2020 Sep;40(5):557-66. 
  9. Kinoshita N, Konno Y, Hamada N, Kanda Y, Shimmura- Tomita M, Kaburaki T, Kakehashi A. 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(1):12750. 
  10. Huang J, Mutti DO, Jones-Jordan LA, Walline JJ. Bifocal & Atropine in Myopia Study: Baseline Data and Methods. Optom Vis Sci. 2019 May;96(5):335-344. doi: 10.1097/ OPX.0000000000001378. 
  11. Bullimore MA, Brennan NA. Myopia Control: Why Each Diopter Matters. Optom Vis Sci. 2019 Jun;96(6):463-465. 
  12. Gifford KL. Childhood and lifetime risk comparison of myopia control with contact lenses. Cont Lens Anterior Eye. 2020 Feb;43(1):26-32. 
  13. Bullimore MA, Ritchey ER, Shah S, Leveziel N, Bourne RRA, Flitcroft DI. The Risks and Benefits of Myopia Control. Ophthalmology. 2021 May 4:S0161-6420(21)00326-2. 
  14. Ubel PA, Loewenstein G, Schwarz N, Smith D. Misimagining the unimaginable: the disability paradox and health care decision making. Health Psychol. 2005 Jul;24(4S):S57-62. 
  15. Luhmann CC. Temporal decision-making: insights from cognitive neuroscience. Front Behav Neurosci. 2009;3:39. Published 2009 Oct 23. doi:10.3389/neuro.08.039.2009. 
  16. Gifford KL, Richdale K, Kang P, Aller TA, Lam CS, Liu YM, Michaud L, Mulder J, Orr JB, Rose KA, Saunders KJ, Seidel D, Tideman JWL, Sankaridurg P. IMI – Clinical Management Guidelines Report. Invest Ophthalmol Vis Sci. 2019 Feb 28;60(3):M184-M203. doi: 10.1167/iovs. 18-25977. 
  17. Bullimore MA, Johnson LA. Overnight orthokeratology. Cont Lens Anterior Eye. 2020 Aug;43(4):322-332. 
  18. 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(3):258-64. 
  19. Sankaridurg P, Bakaraju RC, Naduvilath T, Chen X, Weng R, Tilia D, Xu P, Li W, Conrad F, Smith EL 3rd, Ehrmann K. 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(4):294-307. 
  20. Walline JJ, Walker MK, Mutti DO, Jones-Jordan LA, Sinnott LT, Giannoni AG, Bickle KM, Schulle KL, Nixon A, Pierce GE, Berntsen DA; BLINK Study Group. 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(6):571-580.
  21. Sankaridurg P, Donovan L, Varnas S, Ho A, Chen X, Martinez A, Fisher S, Lin Z, Smith EL 3rd, Ge J, Holden B. Spectacle lenses designed to reduce progression of myopia: 12-month results. Optom Vis Sci. 2010 Sep;87(9):631-41. 

25.Gwiazda J, Hyman L, Hussein M, Everett D, Norton TT, Kurtz D, Leske MC, Manny R, Marsh-Tootle W, Scheiman M. 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(4):1492-500. 

  1. Yeotikar NS, Chandra Bakaraju R, Roopa Reddy PS, Prasad K. Cycloplegic refraction and non-cycloplegic refraction using contralateral fogging: a comparative study. Journal of Modern Optics. 2007;54(9):1317-1324. 
  2. Queiros A, Gonzalez-Meijome J, Jorge J. Influence of fogging lenses and cycloplegia on open-field automatic refraction. Ophthalmic Physiol Opt. 2008;28(4):387-392. 
  3. Mutti DO, Hayes JR, Mitchell GL, Jones LA, Moeschberger ML, Cotter SA, Kleinstein RN, Manny RE, Twelker JD, Zadnik K; CLEERE Study Group. Refractive error, axial length, and relative peripheral refractive error before and after the onset of myopia. Invest Ophthalmol Vis Sci. 2007. 
  4. Fledelius HC, Christensen AS, Fledelius C. Juvenile eye growth, when completed? An evaluation based on IOLMaster axial length data, cross-sectional and longitudinal. Acta Ophthalmol. 2014. 
  5. Rozema J, Dankert S, Iribarren R, Lanca C, Saw S-M. Axial Growth and Lens Power Loss at Myopia Onset in Singaporean Children. Invest Ophthalmol Vis Sci. 2019;60(8):3091-3099. 
  6. Tideman JWL, Polling JR, Vingerling JR, Jaddoe VWV, Williams C, Guggenheim JA, Klaver CCW. Axial length growth and the risk of developing myopia in European children. Acta Ophthalmol. 2018. 
  7. Hou W, Norton TT, Hyman L, Gwiazda J; COMET Group. Axial Elongation in Myopic Children and its Association With Myopia Progression in the Correction of Myopia Evaluation Trial. Eye Contact Lens. 2018 Jul;44(4):248-259. 
  8. Klaver C, Polling JR; Erasmus Myopia Research Group. Myopia management in the Netherlands. Ophthalmic Physiol Opt. 2020 Mar;40(2):230-240. 
  9. Flitcroft DI, Arumugam B, Bradley A, Chamberlain P. Centile-based analysis of refractive development in the MiSight 1 day Myopia Control trial. ARVO June 2020 Abstracts (2020). 
  10. worldcouncilofoptometry.info/resolution-the-standardof- care-for-myopia-management-by-optometrists/ Accessed 5th October 2021.

Study duration is also a factor, with shorter studies tending to show a larger percentage effect. Recent analysis across multiple treatments has found an ‘initial burst of efficacy’, with up to 40% of the cumulative multi-year total occurring in the first six months, and around 50% occurring within the first year.3 Does this mean we should change treatments every six to twelve months to maximise efficacy? Not necessarily – the reduction in absolute treatment with time could reflect the slowing of myopia progression with age, or an adaptation to the mechanism of the treatment. What this does indicate is that it is erroneous to extrapolate a percentage treatment for any duration longer than that of the specific study on that intervention.

This may seem complex but it actually makes clinical decision making and communication easier. Instead of percentages, analysis has moved to comparing the absolute effects. In one of the most notable myopia papers published in the last year, Noel Brennan and colleagues3 analysed the Cumulative Absolute Reduction in axial Elongation (CARE) and concluded that “no single method of treatment shows clear superiority, with the best of orthokeratology, soft multifocal contact lenses (SMCLs), spectacles and atropine showing similar effect”. The authors then explained the following caveats:

  • Some treatments within these categories (e.g. “SMCLs that prioritise clear vision, progressive addition spectacles and 0.01% atropine”) may be less effective,
  • Side effects and potential for rebound within these categories may influence success, and
  • The clinician should factor in their own skill set, treatment availability, patient and parent preferences and capacity, and regulatory considerations in choosing the ideal treatment.

The clinical message here is to pick the treatment you have available to you, that suits the patient and their family. Based on our current understanding, numerous options appear to work similarly to control myopia; these being dual-focus soft contact lenses,4 orthokeratology (OK),5 the newest myopia controlling spectacles (DIMS and H.A.L.T. technology)6,7 and 0.05% atropine.8 Results for slowing axial elongation, which provide far more accurate scientific results than refraction,9 show that every clinician has multiple, similarly effective options available to them for myopia control.

ADDING ATROPINE

There are currently four studies of 12-24 months duration, on combining atropine with OK: two retrospective involving varied concentrations and two prospective which investigate 0.01% atropine. A 2021 metaanalysis10 investigated the retrospective studies with other short-term randomised controlled trials and found a statistically significant reduction in axial elongation of 0.09mm over one year in combination treatment compared to OK alone.

The two newest, prospective randomised controlled trials11,12 have shown the same outcomes, with more information on the ideal targets and timescale of the effect.

  • Tan et al11 found 0.09mm more reduction in axial elongation over 12 months in 1-4D myopes, with the stronger combined effect found in the first six months only,
  • Kinoshita et al12 found 0.18mm more reduction in axial elongation over 24 months in 1-3D myopes, with the stronger combined effect found in the first 12 months only. There was no effect of adding atropine 0.01% to 3-6D myopes, but this group progressed slower overall than the lower myopes.

The summary of this is that adding atropine to OK appears to increase myopia control efficacy by 0.09mm over one year or 0.18mm over two years. The ideal concentration is likely 0.01% and the ideal targets may be lower myopes, with the effects likely being short-term.

There is currently no other data on combining atropine with optical treatments, although a study on atropine 0.01% with centre-distance +2.50 Add SMCL is underway. Only baseline and favourable short-term tolerance data has thus far been reported.13

CLINICAL COMMUNICATION: BENEFITS AND EFFICACY

When communicating the ‘why’ of myopia control, it is important to consider both the short-term and long-term benefits. As clinicians, the long-term message that there is no safe level of myopia, with each dioptre increasing the risk of lifelong pathology and vision-impairment,14 provides a clear motivation for the preventative benefits of myopia control. Two new analyses of risk-to-benefits compare the short-term risks of contact lens infection with the long-term risks of myopia-associated pathology and vision impairment, with the following findings.

Long-term Benefits 

Firstly, the comparative lifetime risks of contact lens wear commenced at age eight for myopia control, and continued throughout life until age 65, are relatively less than the lifetime risks of vision impairment from myopia-associated pathology when myopia is over 3D or axial length is in excess of 26mm. When only childhood CL wear is considered, the risk comparison is clearly skewed towards the positive impact of CL wear, especially in daily disposable CL wear.15 

Secondly, for an individual, each additional dioptre of myopia is associated with a 58%, 20%, 21%, and 30% increase in the risk of myopic maculopathy, open-angle glaucoma, posterior subcapsular cataract, and retinal detachment, respectively. Modelling indicated that a 3D myope is predicted to experience 4.4 years and, for an 8D myope, 9.6 years of visual impairment. When considering five years of myopia controlling contact lens wear, every one person treated will be saved around one year of vision impairment, on average. By comparison, fewer than one in 38 will experience a loss of vision as a result of myopia control based on estimates.16

These facts and figures provide the clear foundation for the long-term benefits of myopia control. These statements may ring true with parents, or may in fact be difficult for parents to grasp, especially if they have no experience of myopia, ocular disease or vision impairment themselves.17 Instead, the short-term benefits may gain more traction in communication with parents.

Short-term Benefits 

Understanding a concept called ‘temporal myopia’ is important here. Temporal myopia is a psychological phenomenon – a reticence to consider the long-term outcomes of an action when making a choice. Decisions often involve a time factor, and typically we tend to prioritise the present and minimise the value of the future gain or loss from the choice.18 What this can mean in myopia management is that a parent may show better understanding of the short-term gains of commencing myopia control, after which the long-term gains can be framed as an additional benefit.

The short-term benefits of myopia control are the slower progression of refractive change. For example, an eight-year-old child in a single vision correction will progress by around one dioptre in a year.2 If that child goes one year between eye exams, he or she could potentially be spending half of that time with clear distance vision, and half with blur due to progression. With myopia control, that clear-vision-time between eye exams is extended – the eight-year-old spends minimal or even no time suffering blurred vision between eye exams, even more so if the six-monthly eye exams recommended by the International Myopia Institute Clinical Management Guidelines are followed.19

DESCRIBING EFFICACY

As described above, percentage efficacy, expressed in a single study, indicates how well a treatment works compared to a control group. However, it can’t be directly compared between studies as the duration of the study, age and even ethnicity of participants can all influence the percentage.

Percentages can be useful, though, in communicating with parents. Explaining that the best class of treatments slow progression by ‘around half ’ or ‘50%’ communicates that we can’t promise to stop myopia progression, and also helps to set short-term goals for treatment, in line with the duration of the studies. This is based on the evidence-base of dual-focus soft contact lenses,4 OK,5 the newest myopia controlling spectacles,6,7 and 0.05% atropine,8 all slowing axial elongation growth over the duration of their specific studies by around half. OK rates a special mention as the intervention with the largest volume of data, with meta-analyses showing a consistent, robust myopia control effect over several studies with differing settings and participant populations.20

On MyopiaProfile.com, the freely available Myopia Management Guidelines Infographics use these categories for describing efficacy, to help set parental expectations for treatment.

The ‘50%’ category of treatments are the best available options. Based on their studies, myopia progression can be expected to slow by about half, over one to three years’ treatment duration. The next-best options slow progression by ‘about a third’, with axial length control outcomes of around 33% in their specific studies. These ‘next-best’ options include bifocal and prismatic bifocal spectacles,21 extended depth-of-focus22 and continuous aspheric centre-distance multifocal contact lenses,23 and 0.025% atropine.8 The less effective treatments include peripheral defocus spectacles,24 progressive addition spectacles25 and 0.01% atropine,8 based on current data. Figure 1 shows this comparison, with the ‘gold star’ awarded to OK for the reason described.

GAUGING SUCCESS

After setting expectations and commencing a myopia control treatment plan, how can we tell if the treatment is working? Using data on typical, single-vision corrected progression in myopic children, we can gauge success over one year based on refraction, using the percentage treatment ‘categories’ as described above. The free-to-download Myopia Profile Managing Myopia Guidelines Infographics provide support to do this, with Figures 2 and 3 providing an example. The latest recommendations are to judge treatment success after a minimum of one year, to account for potential seasonal variation in myopia progression.3

Figure 2 shows the amount of myopia progression per year for a child, corrected with single vision distance spectacles, based on meta-analysis data.2 This could be considered the ‘no treatment’ scenario, with 0% efficacy to slow progression. Figure 3 shows this annual progression reduced by half, for the ‘50%’ category of treatments as previously described. If a child progresses by less than, or equivalent to this annual amount, this can be considered a good outcome. If the child progresses by close to the single-vision amount, then the treatment is not working as expected. Modifiable factors influencing treatment success can include compliance, wearing time and user error, so these should be investigated with the patient and parents. Visual environment should also be discussed with all myopic children – managing the near work environment with appropriate working distances and regular breaks, plus decreasing leisure screen time and increasing outdoor time as much as possible.19

When using this method to gauge success of myopia management, consideration must be given to achieving the most accurate refraction possible, either by cycloplegia19 or using fogging techniques with retinoscopy, subjective refraction or open-field autorefraction. Using these latter techniques render results typically within 0.25D of a cycloplegic result.26,27 When using axial length to gauge success, optical biometry techniques are the most accurate, being around seven times more accurate to detect small changes than refraction. By comparison, ultrasound techniques are no more accurate than refraction.9

Using absolute measures, and comparing from visit-to-visit, myopia control success can again be gauged in reference to the ‘untreated’ progression and expected impact of the treatment. Figure 4 shows a summary of available research on how much axial length growth is typically observed in emmetropes (as a normal process of emmetropisation) and in untreated myopes wearing single vision distance correction.28-32 So, what does myopia control success look like?

  • For children under age 10, early onset and faster progression of myopia puts them at greater risk of high myopia.1 If ‘untreated’ myopia progression is typically greater than 0.3mm per year, then slowing annual progression to less than this is the ideal outcome. Since emmetropes of that same age progress by 0.1-0.2mm per year, slowing progression to this rate is an excellent outcome.
  • For pre-teen and teenage progressing myopes, slowing their axial elongation to less than the ‘untreated’ average of 0.2mm per year is an ideal outcome. Slowing to less than 0.1mm per year is an excellent outcome, considering that emmetropes of the same age show axial elongation of around this amount, ceasing typically by age 12 to 13.

Many of the latest instruments, designed specifically to measure axial length for myopia management, incorporate additional functionality such as auto-refraction and keratometry (the Oculus Myopia Master) or topography and pupillometry (Topcon Myah). Additionally, they include axial length growth charts to support gauging progress and reporting success. These axial length percentile growth charts provide an individualised approach, rather than gauging a child’s outcomes against an average. They allow a child’s axial length to be compared against their peers to set the proactivity of treatment goals and, as such, treatment success is determined by a reduction in their percentile rank over time.33

Scientists are still seeking to understand how many percentile ranks indicate treatment success, with only one research abstract so far superimposing the MiSight dual-focus contact lens three-year clinical study data4 on a percentile chart. The findings were that the control group tracked along their mean centile with minimal change over three years – they didn’t progress faster or slower compared to average. By comparison, the MiSight wearing children reduced by a mean of 10.7 centile points.34 Perhaps this indicates a reasonable target for the ‘best’ category of treatments – time, and more science, will tell.

As practitioners, we should measure treatment outcomes over a year to account for seasonal variation in myopia progression, and review the patient every six months; at those interim appointments, assessing suitability, compliance and vision/eye health outcomes.3,19

WHAT TO DO IN PRACTICE

In April 2021, the World Council of Optometry made a unanimous resolution that myopia management must be adopted as a standard of optometric care.35 This was defined as:

  • Mitigation: attempting to prevent or delay onset of myopia by providing advice on the visual environment and watching for pre-myopia,
  • Measurement: providing regular comprehensive vision and eye health examinations for myopic children, including measuring refraction and axial length where possible, and
  • Management: addressing patients’ needs today to correct and control myopia with evidence-based interventions.

This means that we each now have an imperative to discuss myopia risk factors and the visual environment, identify children at risk of myopia, undertake regular eye exams (advised every six months by the International Myopia Institute)19 and offer myopia correction and control. It makes sense to consider our optical treatments (spectacles and contact lenses) as first line for myopia management as they both correct myopia and slow its progression.

Myopia management offers the opportunity to deliver better care and clearer vision to our young patients, while also optimising their chances for improved lifelong eye health and vision outcomes. Additionally, it is an unparalleled opportunity for professional growth and challenge, engagement with the leading scientific edge of eye care, and building expertise. While it involves interdisciplinary care and awareness, myopia management starts with optometry. There are numerous educational and clinical resources available to support this process – the time to get started is now.

To earn your CPD hours from this article, visit mieducation.com/myopia-management-practisingwith- the-latest-evidence-base. 

Dr Kate Gifford, PhD, BAppSc(Optom)Hons, FAAO is a clinician-scientist and peer educator in private practice in Brisbane. She holds four professional fellowships, over 80 peer reviewed and professional publications, and has presented over 160 conference lectures around the world, primarily on clinical myopia management. Dr Gifford is the Chair of the Clinical Management Guidelines committee of the International Myopia Institute and lead author on their report. She is a co-founder and director of the education platform Myopia Profile. 

References 

  1. Chua SY, Sabanayagam C, Cheung YB et al. Age of Onset of Myopia Predicts Risk of High Myopia in Later Childhood in Myopic Singapore Children. Ophthal Physiol Opt 2016;36:388-94. 
  2. Donovan L, Sankaridurg P, Ho A et al. Myopia Progression Rates in Urban Children Wearing Single-Vision Spectacles. Optom Vis Sci 2012;89:27-32. 

3. Brennan NA, Toubouti YM, Cheng X, Bullimore MA. Efficacy in myopia control. Prog Retin Eye Res. 2020 Nov 27:100923. 

  1. 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 
  2. Sun Y, Xu F, Zhang T, Liu M, Wang D, Chen Y, Liu Q. Orthokeratology to control myopia progression: a metaanalysis. PLoS One. 2015 Apr 9;10(4):e0124535. 
  3. Lam CSY, Tang WC, Tse DY, Lee RPK, Chun RKM, Hasegawa K, Qi H, Hatanaka T, To CH. Defocus Incorporated Multiple Segments (DIMS) spectacle lenses slow myopia progression: a 2-year randomised clinical trial. Br J Ophthalmol. 2020 Mar;104(3):363-368. doi: 10.1136/bjophthalmol-2018-313739. 
  4. 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. 2021:318367. 
  5. Yam JC, Jiang Y, Tang SM, Law AKP, Chan JJ, Wong E, Ko ST, Young AL, Tham CC, Chen LJ, Pang CP. 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(1):113-124. 
  6. Wolffsohn JS, Kollbaum PS, Berntsen DA, Atchison DA, Benavente A, Bradley A, Buckhurst H, Collins M, Fujikado T, Hiraoka T, Hirota M, Jones D, Logan NS, Lundstrom L, Torii H, Read SA, Naidoo K. IMI – Clinical Myopia Control Trials and Instrumentation Report. Invest Ophthalmol Vis Sci. 2019;60(3):M132-M160. 
  7. 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(2):98-103. 
  8. 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 and Physiological Optics. 2020 Sep;40(5):557-66. 
  9. Kinoshita N, Konno Y, Hamada N, Kanda Y, Shimmura- Tomita M, Kaburaki T, Kakehashi A. 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(1):12750. 
  10. Huang J, Mutti DO, Jones-Jordan LA, Walline JJ. Bifocal & Atropine in Myopia Study: Baseline Data and Methods. Optom Vis Sci. 2019 May;96(5):335-344. doi: 10.1097/ OPX.0000000000001378. 
  11. Bullimore MA, Brennan NA. Myopia Control: Why Each Diopter Matters. Optom Vis Sci. 2019 Jun;96(6):463-465. 
  12. Gifford KL. Childhood and lifetime risk comparison of myopia control with contact lenses. Cont Lens Anterior Eye. 2020 Feb;43(1):26-32. 
  13. Bullimore MA, Ritchey ER, Shah S, Leveziel N, Bourne RRA, Flitcroft DI. The Risks and Benefits of Myopia Control. Ophthalmology. 2021 May 4:S0161-6420(21)00326-2. 
  14. Ubel PA, Loewenstein G, Schwarz N, Smith D. Misimagining the unimaginable: the disability paradox and health care decision making. Health Psychol. 2005 Jul;24(4S):S57-62. 
  15. Luhmann CC. Temporal decision-making: insights from cognitive neuroscience. Front Behav Neurosci. 2009;3:39. Published 2009 Oct 23. doi:10.3389/neuro.08.039.2009. 
  16. Gifford KL, Richdale K, Kang P, Aller TA, Lam CS, Liu YM, Michaud L, Mulder J, Orr JB, Rose KA, Saunders KJ, Seidel D, Tideman JWL, Sankaridurg P. IMI – Clinical Management Guidelines Report. Invest Ophthalmol Vis Sci. 2019 Feb 28;60(3):M184-M203. doi: 10.1167/iovs. 18-25977. 
  17. Bullimore MA, Johnson LA. Overnight orthokeratology. Cont Lens Anterior Eye. 2020 Aug;43(4):322-332. 
  18. 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(3):258-64. 
  19. Sankaridurg P, Bakaraju RC, Naduvilath T, Chen X, Weng R, Tilia D, Xu P, Li W, Conrad F, Smith EL 3rd, Ehrmann K. 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(4):294-307. 
  20. Walline JJ, Walker MK, Mutti DO, Jones-Jordan LA, Sinnott LT, Giannoni AG, Bickle KM, Schulle KL, Nixon A, Pierce GE, Berntsen DA; BLINK Study Group. 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(6):571-580.
  21. Sankaridurg P, Donovan L, Varnas S, Ho A, Chen X, Martinez A, Fisher S, Lin Z, Smith EL 3rd, Ge J, Holden B. Spectacle lenses designed to reduce progression of myopia: 12-month results. Optom Vis Sci. 2010 Sep;87(9):631-41. 

25.Gwiazda J, Hyman L, Hussein M, Everett D, Norton TT, Kurtz D, Leske MC, Manny R, Marsh-Tootle W, Scheiman M. 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(4):1492-500. 

  1. Yeotikar NS, Chandra Bakaraju R, Roopa Reddy PS, Prasad K. Cycloplegic refraction and non-cycloplegic refraction using contralateral fogging: a comparative study. Journal of Modern Optics. 2007;54(9):1317-1324. 
  2. Queiros A, Gonzalez-Meijome J, Jorge J. Influence of fogging lenses and cycloplegia on open-field automatic refraction. Ophthalmic Physiol Opt. 2008;28(4):387-392. 
  3. Mutti DO, Hayes JR, Mitchell GL, Jones LA, Moeschberger ML, Cotter SA, Kleinstein RN, Manny RE, Twelker JD, Zadnik K; CLEERE Study Group. Refractive error, axial length, and relative peripheral refractive error before and after the onset of myopia. Invest Ophthalmol Vis Sci. 2007. 
  4. Fledelius HC, Christensen AS, Fledelius C. Juvenile eye growth, when completed? An evaluation based on IOLMaster axial length data, cross-sectional and longitudinal. Acta Ophthalmol. 2014. 
  5. Rozema J, Dankert S, Iribarren R, Lanca C, Saw S-M. Axial Growth and Lens Power Loss at Myopia Onset in Singaporean Children. Invest Ophthalmol Vis Sci. 2019;60(8):3091-3099. 
  6. Tideman JWL, Polling JR, Vingerling JR, Jaddoe VWV, Williams C, Guggenheim JA, Klaver CCW. Axial length growth and the risk of developing myopia in European children. Acta Ophthalmol. 2018. 
  7. Hou W, Norton TT, Hyman L, Gwiazda J; COMET Group. Axial Elongation in Myopic Children and its Association With Myopia Progression in the Correction of Myopia Evaluation Trial. Eye Contact Lens. 2018 Jul;44(4):248-259. 
  8. Klaver C, Polling JR; Erasmus Myopia Research Group. Myopia management in the Netherlands. Ophthalmic Physiol Opt. 2020 Mar;40(2):230-240. 
  9. Flitcroft DI, Arumugam B, Bradley A, Chamberlain P. Centile-based analysis of refractive development in the MiSight 1 day Myopia Control trial. ARVO June 2020 Abstracts (2020). 
  10. worldcouncilofoptometry.info/resolution-the-standardof- care-for-myopia-management-by-optometrists/ Accessed 5th October 2021.

DECLARATION

DISCLAIMER : THIS WEBSITE IS INTENDED FOR USE BY HEALTHCARE PROFESSIONALS ONLY.
By agreeing & continuing, you are declaring that you are a registered Healthcare professional with an appropriate registration. In order to view some areas of this website you will need to register and login.
If you are not a Healthcare professional do not continue.