September 17, 2005
How a squeeze at night can give you vision of a new life without glasses
A TECHNIQUE that corrects short sight as you sleep could give millions of people 20/20 vision without the need for spectacles.
Orthokeratology, now becoming widely available in Britain, uses contact lenses worn at night to correct the curvature of the eye. When you wake up in the morning and remove the lenses, you can see perfectly.
The effect lasts long enough to get you through the day before the lenses are replaced again at night.
Unlike laser surgery, the effects are not irreversible. If people find the treatment does not work, they can revert to glasses or conventional spectacles without having made any permanent changes.
There is even some evidence that the lenses may slow down the deterioration of vision in those whose sight would otherwise get steadily worse.
Short-sighted people have eyes that are too powerful, focusing light before it reaches the retina. Orthokeratology works by flattening the cornea so that it is a less powerful lens.
The eye returns slowly to its natural state but this takes long enough to get through an entire day — and for some users, two days — before the world goes fuzzy again.
Louisa Savage, 13, from Northwood, West London, said that what she had gained most from the method was freedom. “It’s brilliant — I’d recommend it to anybody,” she said yesterday at a seminar at the Institute of Optometry in London.
She started to become short-sighted in 2002. Last October she tried orthokeratology lenses and when she got up next morning she could see perfectly. She has had no problems since. “I enjoy swimming and it’s great not having to use contact lenses during the day,” she said. The technique has become affordable since the introduction of a painless, contact-free laser technique for measuring the curvature of each eye.
No 7 Contact Lenses, based in Hastings, uses the data to make hard, gas-permeable contact lenses with a curvature calculated to squeeze each eye gently in the right places.
The method is widely used in the Netherlands, Switzerland, Germany and the US. Ian Goble, of No 7 Contact Lenses, estimates that there are about 18,000 users in Europe.
He said: “Laser surgery, has similar benefits but is irreversible and invasive. That tends to put some people off. Only 3 per cent of people who inquire about laser surgery actually proceed with it.”
Katie Yeo, the company’s professional services manager, said that people aged from 6 to about 60 with typical levels of short sight could benefit. The treatment costs £100 for the initial consultation and provision of the lenses, then £40 a month for continuing care and replacement lenses every six months. This is comparable with what people pay for some forms of contact lens.
The lenses, originally developed by the Dutch company Procornea, are available from several UK suppliers. They are prescribed by High Street opticians who have been trained in the technique.
A study at Ohio State University five years ago showed that after seven nights, seven out of eight volunteers had significant improvements. After two months, all could see clearly.
A study in Hong Kong, published this year, suggests that the lenses slow the development of short sight, but more research was needed to prove this, Ms Yeo said.