A pioneering operation has restored the sight of a 70-year-old man and could be a cure for the commonest form of blindness in the western world.

Macular degeneration is a condition where the retina wears out, leaving sufferers with only peripheral vision. It affects two million people in the UK alone, including 40% of people over the age of 75.

Doctors at the St Paul’s Eye Unit, Royal Liverpool Hospital, believe they have now developed a cure in what is being called “the single most important surgical development for many years.”

The doctors successfully transferred retired dentist John Barr’s vision from a worn-out part of the retina to a healthier area, restoring his sight. The critical part of the retina is a tiny patch called the fovea, which is responsible for fine vision.

Chief opthalmic surgeon David Wong said: “Put simply, it is like moving around a carpet which has a worn patch in it and tucking the worn part away.”

Macular degeneration is most common amongst older people with 40% of those over 75 in Britain suffering from it.

Sufferers lose their central vision, and with it the ability to read, do close up work and recognise faces.

Until now, doctors could only use laser treatment which at best limited the damage but could not improve sight.

The new operation has been theoretically possible since the early 1990s, but it is only with recent advances in micro-surgerical techniques and instrument design that surgeons have dared attempt it.

Now doctors here and in America and Germany are racing to discover the best surgical approach to help the millions of people with macular degeneration.

Important development

Mr Wong said: “I believe this is the single most important surgical development for many years and we are very excited and encouraged by the success so far.

“What we have demonstrated is that there is spare capacity for vision in the eye. Thus, when one part is worn out - as in macular degeneration - another part can be made to take over the work.

“This is a once in a lifetime experience for a surgeon where you take little steps and then suddenly make a giant leap.

“It is the sort of thing every surgeon dreams of because it may transform the lives of so many people.”

Mr Barr said before surgery his eyesight was very poor.

“The main problem was on the stairs. I could not tell where the stairs were because of black spots, I could not read, and I could not see the detail of anything,” he said.

“Now I can look out of the window and see half of Liverpool quite clearly. It is wonderful, it really is.”

Professor Ian Grierson, who heads the Liverpool Hospital’s Foundation for the Prevention of Blindness, said: “Now we need to establish more clearly which patients will benefit, but it likely to be those with a relatively recent loss of vision.”

Professor Grierson predicted that sight could soon be restored by transplanting healthy tissue to replace that worn out through ageing.

A spokeswoman for the Royal National Institute for the Blind said macular degeneration causes 50% of all blindness in the UK.

“Sufferers can still get around, but it affects their quality of life.

“We welcome any sort of pioneering technique that may be able to give hope to people in the future, but this work needs to be replicated in more than one person before people can pin their hopes on it.”