Rose K™ Ltd.

An optometrist in New Zealand, frustrated at how little he could do for patients with a progressive eye condition in which the surface of the cornea becomes cone-shaped, has designed a contact lens to treat it. After a low-key introduction here, the lens is proving a success. The condition known as keratoconus appears to be much more common in New Zealand than it is in Britain. Paul Rose, who practises in Hamilton on the North Island, says that five in every 1,000 people who visit his practice suffer from it.

In Britain, the incidence is about one in 2,000. It normally develops at puberty or in the teens, the first evidence being a blurring and distortion of vision. As the cornea develops its cone shape, it can no longer focus light accurately on the retina. In the early stages glasses can correct vision, but as it progresses contact lenses are needed. The problem, Mr Rose says, is that traditional contact lenses do not fit the awkward shapes of the cornea.

"The existing lenses didn't mimic the eye shape at all well," he says. "My
design incorporates many more curves, and is only possible since
computer-controlled lathes were developed to cut the plastic to precisely the
right shape."

The shapes are so complex that it is impossible for an optometrist to keep a full set on the shelf. Instead, a "fitting set" of 26 lenses is used to work out the correct shape, power and size of the contact lens needed. The data is sent to the suppliers, Nova Contact Lenses, of Hemel Hempstead in Hertfordshire, who use the computer-controlled lathe to produce the right shape.

It nearly always fits perfectly the first time, says Graham Avery of Nova. "Traditional designs are very hit or miss, but 80 to 85 per cent of Rose K lenses fit the first time."

One happy patient is Brenda Holloway, 51, of Caldicot in Gwent. She has suffered since the age of 11 and was told that she would be blind within two years.

"Her case was very advanced," Mr Rose says. "She was registered blind. Now her sight is one or two lines away on the eye-test charts from absolutely normal."

Mrs Holloway, who is confined to a wheelchair by arthritis, says she can now read, do tapestry and watch television. "It is been a miracle," she says. "I am so grateful to Mr Rose for his invention. My life is much easier. I can see and do so much more."

"It's proved a great success," Mr Rose says, "although I only did it in the first place because I wasn't satisfied with what was available for my patients."