What is Myopia?
Myopia is also known as short-sightedness. Near objects are clear but objects in the distance are blurry. This is usually because the eye becomes too long to focus correctly.
For most short-sighted people the main problem is inconvenience. Being dependent on spectacles or contact lenses can limit activities and be frustrating. However, highly myopic eyes are at a greater risk of developing some serious eye conditions such as retinal detachment and glaucoma.
You are most likely to develop short-sightedness if your parents are short-sighted. Myopia is increasing worldwide and is increasing at a rate which can’t just be explained by genetics alone.
Research has shown that more time spent outdoors as a child helps prevent myopia. It doesn’t matter if a child does a lot of reading, this won’t make them short-sighted, and it doesn’t matter if the time outdoors is spent sitting around or playing sports, it’s just that they are outside.
Unfortunately once a child is short-sighted the amount of time spent outdoors doesn’t have any effect on the progression of their short-sightedness.
There is currently no cure for short-sightedness. Even laser surgery in adulthood doesn’t change the length of the eye, just the front surface, so doesn’t change the risk of conditions associated with myopia.
The aim of myopia control is to slow or halt the progression of myopia. Research into myopia has shown that the light going to the periphery of the retina is responsible for eye growth or the lack of it. As normal contact lenses don’t change the way the light hits the peripheral retina they aren’t effective at controlling the length of the eye.
However, other forms of contact lenses have been shown to change the way that the light reaches the peripheral retina whilst still giving clear vision and have had an effect on slowing the progression of myopia. The results vary for individual children and there is no way to predict what the effect will be for a particular child.
Orthokeratology (Ortho-k or Overnight Vision Correction) for Myopia Control
Extensive research worldwide has shown orthokeratology has the greatest effect on the slowing of myopia progression. It is thought that the effect on myopia control may be greatest with orthokeratology because the reshaping of the front of the eye is combined with the refocusing of the light that reaches the peripheral retina. The effect is not guaranteed, as results vary for individual children, but it has never been shown to make children more short-sighted.
Ortho-K lenses are rigid gas permeable contact lenses, made of very high oxygen permeable materials of a type which have been shown to be safe over many years of wear. All lens wear is done overnight so the lenses are not worn out of the house, which means less worry about lost lenses or spectacles! Also, daytime is free of specs and lens wear so children can take part in all activities and sports without having to worry about their vision.
Who Is Suitable for Ortho-K?
We use a variety of Ortho K lenses and may be able to fit people with up to the following degrees of short-sightedness and astigmatism:
• A spherical spectacle prescription of up to -8.00 D
• Astigmatism of up to -2.50D
Orthokeratology lenses are worn overnight to gently reshape the front of the eye so that the lenses can be removed in the morning and give crisp, natural vision all day.
Please download our PDF Fact Sheet
Ortho-K at Specs of Kensington
As well as being experts in all types of contact lens fitting, our Optometrists have attended extensive training programmes in Ortho-k fitting. We will be pleased to advise on suitability and provide the necessary ongoing professional care.