It has been known for some time that those who are near-sighted can have this eye defect corrected by a contact lens technique called overnight orthokeratology. But until now, it was not established exactly how. A new study by experts at the University of Choonhae Health Science in South Korea and the University of New South Wales in Australia, published in the March issue ofthe American Academy of Optometry's journal Optometry and Vision Science, revealed the chief reason for this is because the lenses flatten the front of the cornea. Discussing their findings, researchers Dr Jeong Ho Yoon and Helen Swarbick stated: "Overall, our results support the current hypothesis that the OK refractive effect is achieved primarily through remodeling of the anterior corneal layers, without overall corneal bending."
The study, entitled "Posterior Corneal Shape Changes in Myopic Overnight Orthokeratology", reveal the lens works the same way a brace does with teeth, noted editor-in-chief of the magazine Dr Anthony Adams. He explained: "Wearing these lenses overnight for about six hours is currently the treatment approach for most clinicians who use OK for the temporary correction of low to moderate myopia." Such a discovery may help contact lens makers refine the design of future products to aid those with near-sightedness, including ones that can be worn at different lengths of time to establish the right levels of bending on the cornea.
Those wearing contact lenses due to myopia include sportsmen such as Manchester United goalkeeper David de Gea, so those who have to do so are in good company. Of course, dealing with an eye condition effectively can help improve everyday life, as well as sporting activity. However, as with any kind of lens, how it must be worn may depend on a number of factors. For a lens that does work better when kept in a long time, Blink & Clean eye drops may be needed to keep them lubricated. The latest research, however, may lead to different solutions for wearers in the future.