Prevention and management of childhood progressive myopia: National consensus guidelines

Abstract

Myopia is a major public health problem worldwide, including India, with the global prevalence of myopia increasing rapidly over decades. The clinical and socioeconomic impact of myopia is also expected to rise with rising prevalence. Therefore, the focus has now been shifted to prevent the incidence and progression of myopia. However, there is lack of any standardized guidelines for myopia management. This document aims to generate a national-level expert consensus statement on the management of childhood myopia in the Indian scenario. The expert panel of pediatric ophthalmologists consisted of 63 members who met in a hybrid meeting. A list of topics deliberating discussion in the meeting was provided to the experts in advance and they were instructed to provide their opinions on the matter during the meet. The panel of experts then gave their views on each of the items presented, deliberated on different aspects of childhood myopia, and reached a consensus regarding the practice patterns in the Indian scenario. In case of opposing views or lack of a clear consensus, we undertook further discussion and evaluated literature to help arrive at a consensus. A written document is prepared based on recommendations explaining definition of myopia, refraction techniques, components and methods of workup, initiation of anti-myopia treatment, type and timing of interventions, follow-up schedule, and indications for revised or combination treatment. This article formulates evidence-based guidelines for progressing myopes and pre-myopes and also establishes uniformity in the management of childhood myopia in the country.

Myopia is a major public health problem worldwide, including India, with the global prevalence of myopia being 22.9% (2.7% high myopes). By 2050, it is expected to affect 50% (4758 million) of the world's population, with 10% (938 million) being high myopes.[1] In certain regions of the world, particularly in East Asia and South East Asia, 80%–90% of young adults are reported to be myopes. Although the prevalence in Indian children (5–15 years) is 8.5% in urban and 6.1% in rural areas, considering the huge population of the country, the actual numbers may be staggering. Furthermore, near doubling of myopia prevalence has been noted in the age group of 11–15 years in the past decade.[2] Myopia prevalence in urban India has been projected to spike to 48% by 2050.[3] A significant increment has been noted even in rural Indian children (from 4.6% in 1980–2008 to 6.8% in 2009–2019).[2]

Although multifactorial, lifestyle modifications like less outdoor activity and greater near work related to intensive educational environment along with prolonged use of digital devices are certain factors linked to the current myopia surge.[4,5] Coronavirus disease 2019 (COVID-19) lockdown restrictions in the past 2 years and switchover to digital platform for schooling have made the situation grim.

Myopia is known have huge clinical and socioeconomic impact. Uncorrected myopia is a major cause of visual impairment.[6] Visual complications related to pathological myopia, like retinal detachment, myopic macular degeneration, choroidal neovascularization, myopic traction maculopathy, glaucoma, complicated cataract, and so on, often lead to blindness.[7] At the individual level, myopia is known to cause low self-esteem and poor quality of life. Estimated global productivity loss due to uncorrected myopia and myopic macular degeneration is around US$244 billion per year,[8] with Asia being the worst affected. The economic burden of managing uncorrected refractive error is significant and using estimates of prevalence of uncorrected refractive error in India and the cost of spectacle provision, it would cost approximately 6.3 billion INR (US$131.6 million) and 24.6 billion INR (US$513.7 million) to treat the entire affected Indian population with readymade spectacles and custom-made spectacles, respectively.[9] The clinical and socioeconomic impact of myopia is also expected to rise with rising prevalence. Therefore, the focus has been shifted to preventing the incidence and progression of myopia. However, there is lack of any standardized guidelines for myopia management. Considering the need to urgently address this growing problem and to formulate national consensus statement on prevention and management of childhood myopia, a meeting was organized.

Pediatric ophthalmologists from across India met in a hybrid meet organized on August 8, 2021 to discuss the current practice patterns for childhood myopia encompassing the basic definitions, essential workup, and indications for intervention to slow the progression in myopes and to prevent the development of myopia in pre-myopes. The experts shared their experiences and discussed the challenges currently faced in managing this refractive error.

The objective of the meeting was to generate a national-level expert consensus statement on the management of childhood myopia in the Indian scenario.

Methods

The expert panel of ophthalmologists consisted of 63 members, each of whom has either been fellowship trained in pediatric ophthalmology or predominantly manages pediatric eye conditions in their clinical practice. Over 80 ophthalmologists working in the field of paediatric ophthalmology and childhood myopia were invited, of which 63 were able to attend. All expert panellists and key opinion leaders in the field of paediatric ophthalmology concurred with regards to the lack of clear recommendations as to the exact definition of myopia, refraction techniques, components and methods of workup, initiation of anti-myopia treatment, type and timing of interventions, follow-up schedule, and indications for revised or combination treatment.

A list of topics deliberating discussion in the meeting was provided to the experts in advance, and they were instructed to provide their opinions on the matter during the meet. A draft on the topic was presented, whereby the existing knowledge and global practice patterns were projected. The rest of the panel then gave their views on each of the items presented, deliberated on different aspects of childhood myopia, and reached a consensus regarding the practice patterns in the Indian scenario.

After the presentation, we collated the comments of the expert panel. The final opinions, where a clear consensus was reached, were recorded. In case of opposing views or lack of a clear consensus, we undertook further discussion and evaluated literature to help arrive at a consensus. After the meeting, a written document with final consensus was circulated among a few experts. The final document incorporating all the changes is presented.

Consensus

The International Myopia Institute (IMI) has provided the quantitative and qualitative definition of myopia and structural complications of the disease in IMI white papers.[10] In accordance with this and to maintain consistency with the international standards, the same have been adopted by this committee [Table 1].

Table 1.

Standard qualitative and quantitative definitions of myopia (adopted from IMI)

Term	Definition
Myopia	Qualitative definition
	A refractive error in which rays of light entering the eye parallel to the optic axis are brought to a focus in front of the retina when ocular accommodation is relaxed. This usually results from the eyeball being too long from front to back, but can be caused by an overly curved cornea and/or a lens with increased optical power. It is also called near sightedness
	Quantitative definitions
	• Pre-myopia: A refractive state of an eye of ≤+0.75 D and >−0.50 D (SE less than +0.75 D, but more than−0.50 D) in children, where a combination of baseline refraction, age, and other quantifiable risk factors provides a sufficient likelihood of the future development of myopia to merit preventative interventions
	• Myopia: A condition in which the spherical equivalent refractive error of an eye is ≤−0.50 D (SE less than−0.50 D) when ocular accommodation is relaxed
	• Low myopia: A condition in which the spherical equivalent refractive error of an eye is ≤−0.50 and >−6.00 D (SE less than−0.50 D, but more than−6.00 D) when ocular accommodation is relaxed
	• High myopia: A condition in which the spherical equivalent refractive error of an eye is ≤−6.00 D (SE less than−6.00 D) when ocular accommodation is relaxed
Axial myopia	A myopic refractive state primarily resulting from a greater than normal axial length
Refractive myopia	A myopic refractive state that can be attributed to changes in the structure or location of the image-forming structures of the eye, that is, the cornea and lens
Secondary myopia	A myopic refractive state for which a single specific cause (e.g., drug, corneal disease, or systemic clinical syndrome)/lenticular disease (index myopia) can be identified that is not a recognized population risk factor for myopia development

IMI=International Myopia Institute

Risk factors for myopia

Risk factor assessment helps the clinician to predict the future risk of myopia development and progression.

Genetics

Genome–environment-wide interaction study (GEWIS) has revealed that gene–environment interaction is the major cause of increase in myopia. Higher education with a high genetic load has greater risk of developing myopia.[11]

Age

Younger age of onset is associated with greater myopia progression and related vision-threatening complications. Myopia progresses rapidly in children aged 6–11 years.[12] Age may also influence the outcome of anti-myopia therapy.

Gender

Gender differences begin to appear by the age of 9 years. Earlier onset of puberty in girls is associated with increased axial length elongation. Female predisposition for myopia has been noted in a few studies, which has been attributed to lesser outdoor activities and greater involvement in indoor work. Higher myopia prevalence was noted in orthodox Jewish boys as they are more engaged in reading religious texts than girls.[13]

Parental myopia

Myopia is heritable. History of parental myopia is associated with greater risk of developing myopia and early age of onset of myopia. Number of myopic parents is a risk factor for the onset and progression of myopia. The risk increases two-fold with one myopic parent and three-fold when both parents are myopic.[14]

Ethnicity

Myopia in East Asian children progresses more rapidly than their European counterparts. East Asian and South Asian children are more likely to be myopic even if residing in another country. Indians have been presently identified as a low progressing cohort (−0.3 D/year) compared to East Asians (−0.6 to −0.8 D/year).[15]

Baseline refractive error

Less hyperopic or more myopic refractive error at baseline is the most important risk factor predictive of juvenile-onset myopia. The cut-offs of age-normal hyperopia (at baseline) for identifying at-risk group for myopia are <+0.75 D for grade 1 (6 years), ≤+0.50 D for grades 2–3 (7 and 8 years), ≤+0.25 D for grade 4 (9 and 10 years), and emmetropia for 11 years.[16] Amount of baseline myopia may influence the treatment response. Lower myopia is associated with better response to anti-myopia intervention.[17]

Visual environment

Time spent outdoor and amount of near work are major contributors to school-age myopia. Myopic children appear to spend less time outdoors, with 40–120 min of outdoor time associated with reduced myopia incidence. There are higher odds of becoming myopic by 2% for every 1 dioptric hour of extra near work per week (sustained near work [>45 min], reading at a very close distance [<20 cm]).[18]

Educational curriculum

Heavy school curriculum leads to greater near work demand resulting in higher rate of myopia occurrence and faster rate of myopia progression. Extensive engagement in afterschool tuition is associated with high prevalence of myopia. Rate of myopia progression is −0.27 D for every additional year of academics. Higher academic and intelligence quotient (IQ) scores have been associated with increased risk of myopia in Singaporean population.[19]

Workup and management guidelines in childhood myopia

The workup for prevention of onset and progression of myopia in children begins with a comprehensive history and eye examination in children. The expert panel concurred that the pediatric eye examination should include the following.

History

The history should preferably be taken from the person with whom the child spends maximum time (usually the mother). A comprehensive history taking can help identify the potential genetic and environmental risk factors for myopia and help guide management strategy.

Important points that should be included in history are summarized below:

1. Age and gender

2. History of ocular and general health including perinatal history, history of prematurity, birth weight, developmental milestones, and so on

3. History of Down's syndrome, cerebral palsy, and so on

4. Known allergy to any drug

5. Assessment of nutritional status and vaccination history

6. Parental history of myopia – single or both parents and age of onset in parents

7. Number of siblings and their refractive error, if any

8. History of ocular complaints – frequent rubbing of eyes, headache, watering, holding the books too close to read

9. Brief details of child's visual environment such as

   • Amount of time spent outdoors during the day

   • Amount of time spent on near work, type of near-work activities, and so on

   • Digital screen duration, type of digital screen used, and so on

   • Lighting condition at home and at school

10. If already using glasses for myopia:

    • Age of onset of myopia- congenital, childhood, or juvenile onset

    • First glass prescription, present glass power, duration of use

    • Amount of myopia- low, moderate, high, pathological

    • History of pathological changes- peripheral degeneration, macular changes, glaucoma

    • History of progression- frequency of change in power of glasses

    • History of previous myopia control treatments, if any.

Ocular examination

An accurate baseline vision assessment, anterior segment and fundus evaluation, and refraction are essential in the workup of childhood myopia. Some additional tests should also be done based on the cooperation of the child and availability of the instruments.

1. Visual acuity

   • Uncorrected and best corrected distance visual acuity (UCVA and BCVA)- Early Treatment for Diabetic Retinopathy study (ETDRS), Snellen, log of minimum angle of resolution (LogMAR) charts

   • Distance corrected near visual acuity (DCNVA)

2. Pupillary reaction

3. Intraocular pressure (IOP)

4. Slit-lamp examination for anterior segment and ocular surface

5. Dilated fundus examination- Optical coherence tomography (OCT) images and/or fundus photos may be taken for documentation

6. Cycloplegic refraction- A cycloplegic refraction using 2% homatropine or 1% cyclopentolate is a must for children with myopia as lack of cycloplegia will increase the risk of misclassification. Refractive error can be assessed by the following methods:

   • Retinoscopy

   • Autorefractometry: Take at least three readings and record the median.

   • Open-field autorefractors are recommended to minimize variability due to residual accommodation and instrument myopia and should be used for distance readings.

   • Instruments should be validated and calibrated at regular intervals.

   • In case of change in power of glasses, prescribe spectacles based on the current refraction and document the myopia progression in D/year.

Ideally, same method of refraction should be used at baseline and on follow-up.

Certain treatment-specific ocular tests may be indicated in some cases, which are as follows:

1. Axial length measurement:

   • Ultrasound biometry (immersion technique) and/or

   • Optical biometry (IOL Master, Lenstar, etc.)

   • Other ocular biometric parameter (s) such as keratometry (Km), anterior chamber depth (ACD), vitreous chamber depth (VCD), and lens thickness (LT) may be documented for research purposes.

     Multiple measurements should be taken and the mean of the values should be recorded.

2. Binocular vision assessment using these tests, where possible:

   • Stereopsis and Worth four-dot test for distance and near with best correction

   • Accommodation lag or lead- using open-field autorefractors, monocular estimate method (MEM) retinoscopy, dynamic retinoscopy, or aberrometers

   • Amplitude of accommodation using “push-up” method or “minus lens” technique; Royal Air Force (RAF) ruler for measuring near point of accommodation (NPA)

   • Accommodative Convergence/Accommodation (AC/A)ratio- using gradient method or distance–near disparity method

   • Distance and near heterophorias using alternating cover test or Risley prism and Maddox rod, and others

3. Corneal topography may be indicated in suspicious cases of keratoconus or for contact lens fittings. It may be assessed using keratometer, videokeratography (VKG), Pentacam, and so on.

   • Tear-film assessment using Schirmer test and noninvasive tear break-up time (TBUT) is indicated in older children on chronic topical medications or using orthokeratology (OK) lenses.

4. Other exploratory tests that may be done if indicated are:

   • peripheral refraction

   • pupillometry- photopic and mesopic pupil size

   • aberrometry for higher-order aberrations

   • macular OCT for subfoveal choroidal thickness.

Risk factor identification

Risk factor identification is based on child's history. Younger age of onset of myopia, higher baseline myopic refractive error, past progression rate of greater than 0.50 D/year, parental history, decreased outdoor activities, increased near work and digital screen time, and vitamin D deficiency are associated with greater myopia progression.[12-20] Based on this, risk factor stratification may be done for the child. Greater the number of risk factors, higher will be the risk of progression. While these factors can predict the risk of progression, it cannot determine the rate of progression.

Management

Pre-myopes

Children with a refractive state of an eye of ≤+0.75 and >−0.50 D (Spherical Equivalent (SE) less than +0.75 D, but more than −0.50 D), where a combination of baseline refraction, age, and other quantifiable risk factors provides a sufficient likelihood of the future development of myopia, are referred to as pre-myopes[10] and merit preventative interventions.

The management of pre-myopes is not yet defined. We should compare their refractive error to the age-normal values. Specific binocular vision disorders like increased accommodative lag and higher AC/A ratio may be seen in pre-myopes, and therefore need evaluation. We can recommend lifestyle and environmental modifications in pre-myopic children, including increase in outdoor activities up to 120 min/day, reduced near work and decreased screen time, other measures like frequent breaks (20–20–20 rule), ambient indoor lighting, maximizing natural lighting, and adequate posture (preferably sitting) and appropriate reading distance while doing near work (25 inches [about at arm's length] from the computer screen). Progressive addition lenses (PALs) can be prescribed in patients with accommodative lag.

Myopes

The anti-myopia treatment for progressive childhood myopia includes optical, pharmacological, and environmental interventions. There is no evidence, at present, for their use in myopia associated with retinopathy of prematurity, congenital cataracts, and so on. Treatment modalities have been evaluated in children from 4–6 years up to 12–16 years of age, and therefore, the use of these presently available treatment options is currently recommended for this age group.

Optical interventions

Spectacles

Special spectacles designed with near addition aim to reduce or eliminate accommodation lag during extended near work, and those designed with peripheral defocus aim to reduce relative hyperopic shifts in peripheral refractive error.[21-25] The commercially available spectacle designs include defocus incorporated multiple segment (DIMS) spectacles (MiyoSMART, HOYA), spectacles with aspheric lenslets (SALs) (Stellest, Essilor), prismatic bifocals (MyopiLux Max, Essilor), Zeiss Myovision Pro, and others. Bifocals and PAL spectacles are preferred in patients with esophorias and accommodation lag.[21] They are simple to use, easy to fit, and well tolerated and accepted, but their efficacy is less than with other interventions.[26] Recommendations for the prescription of spectacles in children have been previously published.[27]

Contact lenses

OK lens is based on reshaping (flattening) of the cornea resulting in relative myopic shift in peripheral retina. Its benefit is found to be maximum in the first 2 years of therapy.[28] Its advantage is that it eliminates the need to wear daytime correction. The disadvantages are low acceptance in most countries including India, risk of microbial keratitis, frequent nonavailability of products, shortage of trained practitioners for fitting OK lenses, rebound effect noted after treatment cessation, and off-label use.[29,30]

Soft multifocal contact lens (SMFCL) may involve off-label use of presbyopic correction.[31] MiSight^® 1 day (CooperVision)[32] and NaturalVue^® (Visioneering Technologies)[33] are daily disposable lenses specially designed and approved for use in myopia in some countries. SEED 1-day Pure Extra Depth Of Focus (EDOF) soft contact lens is a center-distance contact lens with peripheral add working on extended depth of focus principle has also been used off-label to control myopia and is available in India.[34] Proclear^® Toric Multifocal (CooperVision) lenses have been used in myopia with astigmatism.[35] The disadvantages are the same as for OK lenses. Children may notice mild blurring of vision or changes in their focusing with either OK or SMFCL.

Pharmacological interventions

Low-dose atropine therapy remains the easiest and the most accepted intervention for myopia control in the Indian scenario.[36] Group of Pediatric Ophthalmologists and Strabismologists, Mumbai (GPOS) has recommended the use of 0.01% atropine in progressive simple myopia.[37] It is a nonselective, irreversible antimuscarinic agent which reduces myopia progression by slowing axial length elongation. It is contraindicated in Down's syndrome (due to concerns regarding excessive mydriatic and cycloplegic effects and potential systemic toxicity), congenital syndrome or a heart condition, cerebral palsy, history of asthma or other lung diseases, and in patients taking other medications that may have anticholinergic or antimuscarinic effects, for example, some antidepressants and antihistamines.[38]

The Central Drug Standard Control Organization (CDSCO) has approved the use of 0.01% atropine, and it is commercially available in India. Reconstitution of atropine eye drops in the clinic has been demonstrated to be safe and may be done where it is unavailable commercially. Use of higher concentrations of atropine is off-label and associated with more side effects like blurring of near vision and glare.[39] Informed consent is needed before starting the therapy, especially with off-label interventions. The advantages are that it is easily available, easy to administer, and affordable with minimal side effects, like temporary stinging, burning, blurred vision, sensitivity to light, and allergic conjunctivitis.

Disadvantages include rebound phenomenon noted after stopping the drug, especially with higher atropine concentrations. Tapering the dose and/or frequency of the drug should be considered before stopping it. It should be prescribed with caution in myopes with accommodation lag (one can consider adding bifocals along with atropine in such cases). Other issues related to therapy are unaddressed questions like optimum duration of treatment, concentration, frequency, and time of application, and potential tapering schedule before stopping the drug, and the exact mechanism of action remains unknown.

Lifestyle and environmental influences

We can recommend lifestyle and environmental modifications including increase in outdoor activities up to 120 min/day, reduced near work and decreased screen time, other measures like frequent breaks (20–20–20 rule), ambient indoor lighting, maximizing natural lighting, and adequate posture (preferably sitting) and appropriate reading distance while doing near work (25 inches, i.e. about an arm's length from the computer screen).

Surgical Intervention (in high myopia)

No available surgical option is yet accepted for slowing myopia progression.

When to initiate anti-myopia therapy in myopes?

This is the most crucial question that one must ask before starting any kind of anti-myopia intervention.

• Progression of myopic refractive error ≥−0.50 D/year – It is the most important indication for initiating anti-myopia therapy. Progression can be noted by comparison of the past and present prescription of glasses, or it can be implied based on the history of recent increase or change in the power of glasses.

• Younger age of onset – As most young myopes would progress, especially during pre-teenage years (7–12 years), some advocate targeting this group for starting myopia treatment.

• Parental history of myopia – Parental history of myopia and early age of onset of myopia in parents are important risk factors to consider when initiating myopia control.

If there is no evidence of progression in a patient with minimal risk factors, then it may be preferable to observe such cases and keep them on follow-up with regular cycloplegic refraction. Current treatment modalities are recommended for children from 4–6 years up to 12–16 years of age. However, appropriate consent should be taken from the parents before initiating any treatment.

Selection of treatment strategies

This would be based on the following considerations:

• Rate of progression – Estimation of the rate at which myopia progresses for a given individual may help identify an appropriate strategy.

• Ethnicity – A recent meta-analysis suggested greater myopia control with atropine treatment in children of Asian compared to European ethnicity.[40]

• Baseline refractive error – Myopic refractive error at the time of intervention may influence the treatment response.

• Age – Younger age generally leads to faster myopia progression.

• Binocular vision status – Greater myopia control effects with progressive spectacles were reported in children with larger lags of accommodation and near esophoria.[41]

• Safety, compliance, and cost considerations.

Children who possess multiple risk factors may require more strategic management and frequent review compared to those with little or no associated risk factors. The treatment strategy should be decided after discussing the risks/benefits of treatment, the patient's lifestyle, economic status, and ease of compliance with the patient and parents/guardian. Environmental and lifestyle modifications must be advised with any form of optical or pharmacological intervention.

After the intervention has been initiated, follow-up should be done at the scheduled time and the recommended parameters should be recorded. Keep an eye on the ocular health of the child and examine whenever necessary. On follow-up, analyze changes in refractive error and other ocular parameters and decide the clinical management accordingly [Fig. 1].

Figure 1.

Childhood myopia management strategy

Lay terminology communication with parents and patients

Communication with the parents and patients before initiating anti-myopia therapy using simple layman terms is of utmost importance. Explain that the treatment will not limit the activities of the child and he/she can participate in any activity with appropriate corrections (spectacles or contact lenses). Make them aware about the potential risks associated with progressive myopia and the need for periodic comprehensive examinations including cycloplegic refraction and retinal evaluation. Help parents understand their child's risk profile and ways to reduce exposure to avoidable risk factors. Inform them about myopia control treatment options, expected efficacy, and potential benefits associated with them. Explain to them the risks and associated side effects of myopia control treatment and how we can minimize them.

Take informed consent if the myopia control option involves off-label use.

Advice and clinical care

Children should be encouraged to wear their appropriate myopic correction full time unless asked by the clinician. OK lens wear should be encouraged daily for a minimum of 8 h overnight, and Multi-Focal Soft Contact Lens (MFSCLs) should be worn for at least 5–8 h during school time and for school work at home. Children who are prescribed optical modalities like OK lenses, multifocal spectacles or contact lenses should have spectacles as a back-up when they are not using contact lenses. The children and parents must be asked to monitor and report any acute adverse effect. The patients should be informed about where to report in case of emergency.

We must also encourage the children to develop healthy visual habits, that is, spending more time outdoors, maintaining appropriate reading distance, that is, 25 inches (about at arm's length) from the computer screen, taking regular breaks after continuous near work (20–20–20 rule), fixation change while reading or watching screen, and maximizing indoor and outdoor lighting. Recommendations for healthy screen use behavior are available online.[42]

Review Schedule

The minimum recommended review schedule based on the type of treatment prescribed should be as given in Table 2. This is the minimum recommended review schedule and can be individualized on a case-to-case basis on the discretion of the treating ophthalmologist. The clinical tests that should preferably be done on various follow-up visits are given in Table 3. We can also maintain myopia growth curve or chart that will help monitor the treatment response effectively.

Table 2.

Review schedule

Atropine eye drops	Orthokeratology/soft contact lens	PALs/spectacles
2 weeks	1 day	1 month
2 months	4–7 days	Then six monthly
6 months	1 month
Then six monthly	3 months Then six monthly

PALs=progressive addition lenses

Table 3.

The clinical tests to be done on follow-up of a patient on anti-myopia therapy

Follow-up	Tests on follow-up
For initial follow-ups	• Relevant history related to the treatment, like side effects, compliance, and so on
	• Distance and near Visual Acuity (VA)
	• Atropine specific- pupillometry, IOP
	• OK specific- corneal topography
	• MFSCL and OK specific- Contact Lens (CL) fit
3 months	• All the above and
	• Cycloplegic refraction
	• Ocular health examination
	• Binocular vision assessment including accommodation
Then six monthly	• All the above and
	• Ocular biometry- axial length
Every year	• All the above and
	• Dilated fundus examination

IOP=intraocular pressure, OK=orthokeratology

Analysis of treatment efficacy

The efficacy of the treatment can be analyzed at follow-up in terms of myopia progression, axial length elongation, and change in other relevant parameters.

• Myopia progression – Change in spherical equivalent refractive error from baseline to the last visit

• Axial length elongation – Change in axial length from baseline to the last visit. Refractive error cannot be used as an effective treatment indicator for OK lenses.

• Other parameters – Change in other ocular parameters from baseline/pretreatment visit to the last follow-up visit – ACD, LT, keratometry (Km), binocular vision, and so on.

Treatment duration

Ideally, the treatment should continue as long as the myopia progresses. But long-term efficacy has not been studied for these interventions. The World Health Organization (WHO) currently recommends limiting the duration of atropine treatment to 2 years. Literature supports the safe use of atropine for 2 years and a maximum of 5 years. Similarly, for OK and multifocal contact lenses, mostly, 2-year efficacy is reported. Long-term use of these contact lenses is not contraindicated if the ocular health is maintained.

So, the best approach would be to individualize the treatment and monitor the response on follow-up and prescribe or discontinue the treatment on a case-to-case basis.

Nonresponders/Poor responders

Nearly 10%–20% of patients are nonresponders or poor responders who show progression despite the best of treatment. Increase in myopic refractive error of ≥0.5 D/year despite the best possible intervention is defined as nonresponse/poor response in myopia management. Increase in myopic refractive error of ≥1 D/year despite the best possible intervention is rapid progression.

The nonresponders usually have younger age of onset, both parents who are myopic, higher baseline myopia, and faster progression.[43,44] Environmental modifications should be implemented early in such cases, along with other interventions. These patients may benefit from a trial of higher concentrations of atropine/more frequent dosing regimen (side effects will increase – photochromatic glasses and PALs may be used) along with combination therapy.

When to stop/change treatment

Childhood myopia is known to stabilize in most cases by mid-teens (around 14–16 years of age). The anti-myopia therapy should ideally continue till the myopic refractive error stabilizes. Usually, a treatment period of 2–3 years is acceptable with most interventions. However, the decision should be taken by the treating ophthalmologist. After completion and stopping of any treatment, schedule close follow-up visits to document any myopia progression (either due to rebound effect of treatment cessation or as a natural growth process of myopia). Rebound phenomenon is reported with the cessation of higher atropine concentrations and OK lenses. So, as discussed earlier, tapering may be considered, especially with higher doses of atropine to prevent the rebound effect.

Recommencement of treatment or switching to other treatment modalities may be considered if the myopia progression is significant. Switching to another form of therapy or combined therapy may be considered when myopia progression is not sufficiently controlled in comparison to the expected progression and there are intolerable side effects and compliance issues with the current therapy. Combination therapy of OK with atropine has shown promising preliminary results. Combination of lifestyle modification along with pharmacological or optical interventions must be advised. One must keep in mind that the available anti-myopia therapy can slow the progression, but cannot stop it completely.

Public health initiatives

The public health initiatives to prevent myopia onset and progression are of paramount importance. There is need to create awareness about the disease burden. It is essential to educate all those working in the healthcare community, including ophthalmologists, optometrists, pediatricians, and related policymakers, about the public health costs related to childhood myopia and recognizing that myopia is a public health burden. Several ophthalmological and optometry societies and pediatricians at the national and state levels can play an important role in this regard. There is a need to create educational resources for medical professionals and Information, Education, and Communication (IEC) material for the general public, patients and their parents to promote healthy lifestyle choices to prevent and reduce myopic progression. Annual school screening program for early identification of refractive errors and healthier school curriculum with adequate outdoor activities/play during school hours should be advocated. Collaborative research among ophthalmologists, optometrists, and industry to develop novel and affordable interventions for myopia control should be promoted.

Conclusion

The purpose of this article is to formulate evidence-based guidelines for progressing myopes and pre-myopes. This will not only help raise awareness about this understated problem, but also establish uniformity in the management of childhood myopia in the country. The above recommendations for myopia management are based on the current understanding of the disease and are bound to change as new evidence is generated.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.