The new treatment could potentially benefit up to seven per cent of people who suffer from severe epilepsy.

A team from the Victorian Epilepsy Centre in Australia used electrodes and computers to pinpoint an orange-sized tumour in the brain of 32-year-old epileptic Maree Robson.

They used the new technology to remove the tumour and surrounding area - a procedure previously impossible without a high risk of damaging an adjacent area in the brain that controls speech.

Centre director Mark Cook said: "This is a dramatic advance that offers people like Maree surgery that can cure their seizures."

Ms Robson has had epileptic seizures since the age of 12.

Before the operation she had four seizures a week and used four medications to control her condition.

Since the operation she has had no seizures and although she still uses three medications it is hoped eventually that she will only need one.

Ms Robson said: "It has been exciting. I have had seizures for a long time never thinking that this was possible.

"I feel great not having a fit or any seizures. I feel like a new woman."

Grid of electrodes

The technique involved inserting a grid of highly sensitive electrodes onto the surface of the brain to locate the area where the epileptic seizures started.

The grid was removed but its details retained by a computer and fused with information from a CAT scan and medical resonance imaging to create a three-dimensional virtual map.

During the operation, which involved seven hours of surgery in two sessions, an electronic pointer and the virtual map allowed the surgery to be performed with two to three millimetres accuracy.

Neurosurgeon Michael Murphy said: "One of the problems we have had in the past is that although people have used grids before, once you remove the grids it is very hard to remember exactly where the electrodes were."

The surgeons said the technique could be used for epilepsy sufferers who had not responded to medication and who had a brain abnormality, such as a tumour, that showed up on scans.

A spokeswoman for the British Epilepsy Association said: "To be able to pinpoint the epicentre of the epilepsy and to retain that information and develop a three-dimensional virtual map will greatly reduce the risk of damaging areas surrounding the tumour during invasive surgery.

"This development will be greatly welcomed by those who need to have surgery when it becomes more widely available. The BEA welcomes new developments such as this as they will inevitably help to improve the quality of life for people with epilepsy."