A group of eye charities claimed on Wednesday that the sight of some patients is being put at risk by a "postcode lottery" of NHS treatment.

Age-related macular degeneration (AMD), the most common form of blindness in the UK, leaves sufferers blind after between three and five months from diagnosis. It can be treated in 10 per cent of cases by photo-dynamic therapy (PDT), a laser treatment that is only available in eleven hospitals in Britain.

The AMD alliance, a group of charities including the Royal National Institute for the Blind and Age Concern England, is calling for availability of PDT to be extended throughout the UK to reduce the time between diagnosis and treatment. A request has been made to the National Institute for Clinical Excellence (NICE), which is currently investigating it's cost-effectiveness.

Steve Winyard, head of public policy at RNIB and a board member of the AMD Alliance, said: "PDT is a vital sight saving treatment. It is appalling that people may go blind because the treatment is only available in certain areas and in other areas waiting lists are too long. As many as 5000 people's sight could be saved if PDT was available nationally. PDT is routinely available in Europe, it's time the UK caught up."

A Department of Health spokesperson said: "We can't comment in detail while the NICE appraisal process is underway. But we're determined to end postcode prescribing. Patients should have access to the latest, effective drugs and treatments and that's exactly why NICE is looking at this treatment. We await NICE's final recommendations.

"When considering the funding of any treatment currently being appraised by NICE, or where no appraisal has been commisioned, funding authorities are expected to use existing prescribing arrangements and consider the evidence available to them on the clinical effectiveness of the treatment."