As the technology, options and knowledge increases in the field of myopia management, we are getting better at detecting myopia risk as well as monitoring and managing progression. When is the most appropriate moment to intervene and start myopia management?
Myopia management comes in many forms, from modifying environmental factors like reducing screen time and increasing outdoor time, to proactive optical or pharmacological options, where the latter are available and appropriate to scope of practice. Every child is different, and needs a solution tailored to their unique needs and that of their family.
Age under 8 and refraction at least +0.75
If children have an age-normal amount of hyperopia, they are at much less risk of progressing to myopia than children whose eyes are growing too quickly towards emmetropia.1 Other risk factors, such as parental myopia,2 low amount of outdoor time3 and binocular vision issues should be assessed and addressed. Generally, all children are recommended to have an annual eye examination.4,5
Manage with: Visual environment advice on less screen time and more outdoor time.
Good visual hygiene habits should be encouraged in all children – with myopia or without. World Health Organization screen time guidelines recommend that children aged 5-17 have no more than 2 hours of recreational screen time per day, and only one hour per day for pre-school aged children.5 This has multiple health benefits, not just for vision – it has been shown that when families monitor children’s digital access, the amount of screen time reduces and sleep and school performance improve.6
Outdoor time also has positive outcomes for all children. There are numerous physical and psychological benefits to encouraging children outside, and there is good evidence for this delaying the onset of myopia.3 Encourage all children to put down their screens and get out and about.
Age under 8 and less than +0.75D
The strongest predictor of future myopia is a refraction of less than +0.75D of hyperopia at this early age. The CLEERE study found that future myopia, by age 13, is highly likely in children who are less than +0.75D age age 6-7 years.1 These are the children to watch, and consider for shorter intervals between eye examinations and behavioral advice on the visual environment.
Manage with: Close observation, growth chart plotting and early intervention.
Age under 12 and axial length growth of 0.1mm per year
As part of the emmetropization process, children will have a normal amount of eye growth that may not contribute to myopia. The corneal curvature is quite stable, while the growth of axial length is balanced by flattening of the crystalline lens.7 The Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study, which collected data on children over an 11 year duration, found this axial length growth in children who remained emmetropic was steady from ages 6 through to the early teenage years, at approximately 0.1mm per year.8
Manage with: Close observation, and general visual environment and lifestyle advice – which is useful for all children
An emmetropic child with a family history of myopia
Having one myopic parent triples the risk of a child becoming myopic, while two myopic parents increases a child’s risk by 6 times.9 When a child has one (or both) parents who are highly myopic, children are at risk of developing myopia themselves and also progressing rapidly.10 Having siblings who are already myopic also increases risk, independently to parental myopia.11
Children who participate in outdoor sport and activities when they are in early primary school are also less likely to have myopia by early high school,9 so consider the risks of children who don’t get much outside time, especially in response to recent home confinement due to COVID-19. Raise these risks with families early and discuss the many benefits of lifestyle modification and monitor children closely for myopia onset.
Manage with: Close observation, growth chart plotting and early intervention
When a child is already myopic
CLEERE found the fastest axial growth occurred in the year before myopia onset, where future myopes grew by 0.33mm, with 0.20mm growth or more per year after the initial myopia onset. 8
We know that there is no safe level of myopia, and the risks of myopia rapidly escalate with increasing myopia.12 We understand that the benefits of myopia control outweigh the risks of allowing myopia to progress unchecked,13 and that every dioptre matters in terms of absolute risk of myopia-associated pathology.14 If a child presents with myopia, the time to begin proactive myopia management is immediately.
Manage with: There is no one-size-fits-all approach to myopia management, and the treatment which best suits each child and their family needs to be selected. There is no apparent superior method of treatment when considering the best of the spectacle, contact lens and pharmacological options (where available) – they each have various benefits, so all young myopes should be recommended a treatment suitable to them.15