The effectivity of treatment has the mantra ‘younger the better’
Emerging myopes can be predicted before they become myopic. Most clinicians advocate close monitoring and fitting upon the first signs of myopia. The decision to commence fitting contact lenses needs to be offset by the maturity of the child in handling lenses and the risk of infection. Handling of lenses is rarely a barrier to the child and we are seeing more and more children becoming myopic at a younger age. This is a professional judgement based on the patient and the risk. Risks such as parental myopia, sibling myopia, lifestyle and many other factors.
An interesting work which visualize the importance to start with myopia control treatment as soon as the first indication occur did Sharon Y. L. Chua et al in "Age of onset of myopia predicts risk of high myopia in later childhood in myopic Singapore children". In the conclusion of a study write Sharon Y.L. Chua, "that myopic Asian children who developed myopia at a younger age have a higher risk of high myopia. The Age of onset of myopia or duration of myopia progression till 11 years emerged as the strongest predictor of high myopia in later childhood, more than other factors."
The most effective time for starting myopia control is for children under-12 when myopia commonly develops. However, we are seeing the progression of myopia through into young adulthood, especially when studying or high near task demands. The clinical judgment of the age of discontinuing is very individual and needs to be considered with regard to educational demands the minor impact on visual quality if driving. Presbyopes are not restricted from driving in multifocal contact lenses so even in the late teenage early 20s it might be considered appropriate to continue with the customised contact lens fitting.