Myopia, commonly called short-sightedness makes it difficult to see distant objects clearly. It is a very common condition. Myopia's onset is typically in the mid-teens and less frequently later in the twenties. There is considerable debate about whether myopia is inherited or whether it is exacerbated by excessive close work.
Myopia (shortsightedness) is increasing around the world, with many calling it an epidemic. In the US for example the prevalence of myopia has increased markedly in the last 30 years – from 25% in the early 1970s, among those aged 12 to 54 years, to over 40% now. Australians show similar trends. Aside from the burden of needing spectacles or contact lenses to function normally, patients with myopia have a much higher risk of blinding eye disease later in life.
Here at Outlook Eye Centre we offer treatment options to slow the progression of myopia, protecting your eye health into the future.
The aim of myopia is to provide clear distance vision in addition to slowing down or stopping the progression of myopia
Myopia control does not reverse the amount of myopia that is present. It aims at minimising the total amount of growth after initiating treatment so that we limit the incidence of high myopia. High myopia is associated with significant sight-threatening risks later in life such as cataract development, retinal detachment and macular degeneration.
The science behind myopic progression is complex and numerous studies have been performed in this area. Over the past decade there have been significant advances in this field such that we now have a better understanding of what causes myopia to progress. Researchers now believe that a major factor in the progression of myopia is peripheral hyperopia (or long-sightedness). The eye elongates as a result of this peripheral hyperopic defocus which in turn causes an increase in the central myopia.
Myopia control treatment options offered at Outlook Eye Centre
Prescribing standard spectacle lenses or contact lenses will generally do nothing to halt the progression of shortsightedness. As a result, the patient will require frequent spectacle lens updates and will be put at risk of sight-threatening problems in the future. Unfortunately, the lengthening of the eye which causes myopia cannot be reversed, making it critical to control myopia sooner rather than later. Options for myopia control include:
Orthokeratology (Ortho-k) - http://www.outlookeyecentre.com.au/your-vision/item/orthokeratology
Ortho-K is use of rigid contact lenses – which are worn during sleep – to remould the shape of the cornea to reduce or eliminate myopia. In some ways this is similar to the use of dental braces by an orthodontist to straighten crooked teeth. The cornea is highly elastic and always returns to its original shape. For this reason, retainer contact lenses are worn typically four to seven nights per week.
The greatest appeal of Ortho-K is that the patient is not required to wear spectacles or contact lenses during the day. Hence, Ortho-K provides clear, unaided vision through all waking hours while at the same time helping to control the progression of the myopia.
Atropine eye drops: Atropine is an anti-muscarinic drug that typically causes pupil dilation and cycloplegia. Atropine eye drops give one of the highest levels of myopia control. Recent studies show that much lower concentrations of these eye drops can be used safely to obtain a good level of control, without the side effects of higher doses. Drops are used once daily in conjunction with spectacles or contact lenses
Multifocal soft contact lenses: this avenue seeks to control myopic progression by correcting for peripheral hyperopic defocus. They are the same lenses that are worn by people over 45 to help read clearly and are typically a monthly-disposable lens worn only during waking hours.
If ortho-K lenses are not suitable, these soft contact lenses may be discussed with Shannon as an alternative option, and may be used in conjunction with atropine drops to improve the myopia control effect.
There are currently no published long-term studies that satisfactorily answer the question of how long myopia control treatment must be sustained. Clinical experience, however, suggests that children undertaking treatment must continue at least until the end of their teenage years. Alternatively, if the myopia has been shown to be stable for an extended period of time, then consideration can be given to discontinuing the treatment.
Source: Kate Gifford, Jim Kokkinakis