British experts are pioneering a treatment using stem cell therapy to improve the sight of people born with a rare genetic eye disorder.
Stem cells taken from dead donors, living relatives or even the patients themselves are grown in a laboratory until they form sheets and then transplanted on to the surface of the cornea.
The team from the Queen Victoria Hospital in East Grinstead, worked on sufferers of a rare genetic eye disorder called aniridia.
It is a condition where people are born with no iris and who later develop problems with the surface of their eye, resulting in pain and loss of vision.
Until now very little could be done for the patients, most of whom go on to become virtually blind.
But eye specialist Sheraz Daya, from the Queen Victoria Hospital, said stem cell treatment appears to halt progress of the condition, which affects up to 1,000 people in the UK.
Four patients have so far received the treatment successfully in one eye and reported an improvement in their comfort and vision, and now await treatment in their other eye.
All had little or no vision because they had few or no limbal stem cells under the eyelid which help keep the surface of the cornea clear and healthy.
Mr Daya believes the stem cell transplant somehow triggered the production of new limbal stem cells in the patients.
He said: "We think the donor cells have attracted stem cells from the bone marrow to make new limbal stem cells, which have arrived at the eye through the bloodstream."
Mr Daya said that if donor cells could trigger stem cell regeneration in eyes, they could also work in other organs such as the liver and pancreas.
He said: "Once we understand what has prompted their growth, then we can understand what they can do for other parts of the body.
"It's extremely exciting."
Mr Daya and his team at the corneoplastic unit at the Queen Victoria Hospital spent more than seven years perfecting their technique.
Outcomes of the trial will be revealed at an international conference of eye specialists in New Orleans later this year.