Review of myopia control options to reduce myopia progression in children

Introduction
Myopia prevalence is increasing especially in some Asian countries. Whilst the causation of myopia remains unclear, several treatment options are applied and discussed in the literature. In this presentation various options will be reviewed. The presentation will focus on optical intervention methods.

Discussion
To reduce the progression of myopia a variety of options is currently commercially available. Intervention methods can be divided in pharmaceutical interventions and optical methods.
Drug treatments involve the use of atropine or caffeine. The use of atropine for myopia control has a long history and recent work has shown that even a low dose of atropine has a positive effect with minimal side effects. Caffeine also seems to be successful in reducing myopia progression and at the same time, children are not affected by its side effects.
Animal experiments have shown that eye growth is driven by optical signals, which allows the conclusion that optical intervention methods are an option for eyecare professionals.
Optical interventions focus on the use of centre-distance multifocal contact lenses, based on the peripheral refraction theory. These lenses attempt to reduce relative peripheral hyperopia and therefore stop axial length growth signals. However, some recent data analysis could not prove this theory.
By chance, it was discovered that the use of orthokeratology contact lenses reduces myopia progression rates. The reason for this effect is currently unclear. One possible explanation is the manipulation of higher-order aberrations, in particular coma. At present, orthokeratology lenses seem to outperform soft multifocal contact lenses.
In addition to options available in Europe, special myopia-controlling soft contact lenses are readily available in far-East Asia, such lenses have a customised optical design.
Besides pharmaceutical and optical interventions, general agreement appears to exists between researchers that time spent outdoors is an important factor, perhaps even the most important factor, to reduce myopia progression. In that context the role of light levels is currently been researched.

Conclusions
A variety of options are available to reduce myopia progression in children. Further research is needed to better understand the principle of myopisation.