Short-sightedness cured while you sleep with revolutionary lens worn only at night

For the millions of people who daily polish their glasses or peel away their contact lens, help is in sight. A revolutionary procedure is able to correct short-sightedness while you sleep.

For the millions of people who daily polish their glasses or peel away their contact lens, help is in sight. A revolutionary procedure is able to correct short-sightedness while you sleep.

Which is good news for the 50 per cent of the UK population who need glasses.

Orthokeratology, otherwise known as ortho-k, uses rigid contact lenses, similar to gas permeable ones, made individually for each person. No 7 Contact Lenses, one of the companies behind the technology, has enabled opticians to email topographical maps of their patients' corneas to its laboratory, where lenses are made.

The lenses are worn as normal but are left in overnight, and gradually alter the shape of the cornea by less than a hair's breadth. They must be worn continually for at least three nights a week. Many opticians believe that ortho-k can also slow down the progress of short-sightedness, making the treatment especially valuable for children.

But the main advantage is that the user is free to take part in sports, go swimming and consume hot drinks during the day without losing their lenses or steaming up their glasses.

"I started orthokeratology a week ago," says one convert, Janice English. "It's very useful because I swim a lot. I haven't worn my glasses since I started. It's amazing."

Because the cornea is highly elastic, orthokeratology is non-permanent and reversible, unlike more radical laser surgery. However, American scientists are now working on ways of making it more permanent.

Despite the heavy initial outlay on equipment, the number of optometrists offering the treatment has tripled in the last year. The technique is fast growing in popularity, with some opticians claiming to be able to correct up to eight or nine degrees of myopia. Some also offer treatment for long-sightedness, although the condition can be corrected only in lesser degrees. A Dutch laboratory is developing a lens that will be able to correct astigmatism.

There are more than 60 opticians in Britain offering regular ortho-k. Many are listed on the official website of the British Orthokeratology Society at www.boks.org.uk.

According to Dr Trusit Dave, an eye specialist who practises in Coventry, the treatment is non-painful and very safe. "With infection occurring in only 5-10 patients in every 10,000, it carries the same risk as ordinary contact lens use," he says.

Ortho-k is not available on the NHS, and Dr Dave charges patients £800 a year. But supporters of the treat ment say it is no more expensive than ordinary lens use.

"Third-generation" soft contact lens will also be available this month. Developed by Johnson & Johnson, they are made of hi-tech silicone; this means they do not dry out as quickly as ordinary soft lenses and are more comfortable.