Using Contact Lenses to Stop Child and Teen Myopia
Myopia, the official name for short-sightedness, generally starts to afflict children from the age of eight onwards. It can occur earlier and here, in Australia, a recent study found that 8.4% of children aged between 4 and 12 suffer from myopia.
Thankfully, using contact lenses can not only improve your child's sight temporarily, but research has shown it can actually slow down the progress of the myopia.
There are two types of contact lenses prescribed to treat myopia: rigid gas permeable (RGP) lenses and Orthokeratology lenses, which are specially designed, smaller RGP lenses.
There are several causes of myopia, but in most cases of simple myopia, the reason is that the eyeball has lengthened. This affects the refraction of light hitting the cornea, thus blurring vision.
Rigid Gas Permeable Lenses (RGP) and Myopia
Whilst many of us as adults prefer to wear soft contact lenses because they mould to the shape of our eye and are more comfortable, for children and teenagers, the hard RGP lenses are actually the better option.
Because these lenses do not change shape to fit the eye but instead maintain their rigid shape, they can help the eye to retain a perfect shape. They provide a constant, gentle pressure onto the eye, thus flattening the cornea, preventing the eye from further changing shape and preventing the myopia from worsening.
RGP Lenses are smaller than soft contact lenses and allow more oxygen to get through to the cornea. They do, however, take more time to get used to than soft contact lenses and are more expensive.
Orthokeratology Lenses and Myopia
Orthokeratology involves wearing specially designed, smaller RGP lenses overnight to correct the eye's shape and thus prevent myopia from worsening. It is also known as Ortho-K or Corneal Refractive Therapy (CRT).
The child or teenager inserts the CRT lenses into their eyes upon going to bed and removes them in the morning. During the day they don't wear lenses or glasses, yet their vision has been shown to dramatically improve and the progress of their myopia to slow down.
Orthokeratology lenses are more uncomfortable than standard RGP lenses, but this isn't usually a problem as the child is asleep whilst wearing them. However, they do take specialist fitting in the first place and you might need to go for several fittings before finding the right fit for your child. An incorrectly fitted Ortho K lens can cause problems such as double-vision or ghosting. So it is important to get the fit right.
Finally, if your optometrist is reluctant to prescribe contact lenses to your child, inform them that a study published in the Journal of Optometry and Vision Science in 2007 recommended that optometrists prescribe contact lenses to children aged 8 onwards.