Treating burst aneurysms by blocking them with platinum coils could offer patients better long-term survival than major brain surgery, researchers say.
A platinum coil is fed through the blood vessels to the brain
Tests of the technique in an international study were halted early in 2002 because results were so good.
Now a longer-term follow-up confirms it does boost the chances of patients - who risk a stroke without treatment - surviving without disability.
The latest study, by the University of Oxford, is published in The Lancet.
A brain aneurysm is a ballooning-out of the wall of an artery in the brain.
It can be associated with high blood pressure and commonly develops in middle age, but the reasons for this are not clear.
Aneurysms are not always life-threatening, but if one bursts it can cause a haemorrhagic stroke.
Every year in the UK about 6,000 patients suffer this kind of stroke. Many are quite young - half are in their 40s and 50s.
Traditional treatment involves surgically opening the skull, and clipping the aneurysm to stop further bleeding.
In contrast, the coiling treatment is performed by making a tiny puncture wound in the groin and feeding the coil through the blood vessels to the brain.
The Oxford team assessed 2,143 patients from 42 neurosurgical centres in Europe, North America and Australia.
They found 23.5% of patients treated with the coil technique were either dead or dependent on others one year after their treatment.
But among the group who underwent full brain surgery the figure was 30.5%.
The researchers also found that the coil patients were more likely to survive up to seven years after treatment than the brain surgery group.
Coil patients were also much less likely to develop seizures.
They were more likely to experience renewed bleeding - but the risk was still low.
Researcher Dr Andrew Molyneux said use of the coil technique could reduce the risk of death or disability by about 24% - potentially saving 74 out of every 1,000 patients from severe problems.
"Our results from following up patients for seven years will be reassuring to patients and doctors alike.
"Although treatment changed from surgery to coiling in many countries after our promising preliminary results in 2002, some countries have been slow to adopt coiling because there was still concern among neurosurgeons over the potential risks of re-bleeding.
"The reassuring thing is that we now have good evidence that the coil treatment is not only better short-term but it is also better in the medium to long-term."
Dr Gavin Britz, of the Harborview Medical Centre in Seattle, said: "Each patient and their aneurysm is different and the decision has to be made about what is in the best interest for each patient.
"Some patients should be clipped and some should be coiled.
"The ultimate decision is complex, including many variables to ensure the most appropriate care."
Dr Peter Coleman, of the Stroke Association: "Rupture of an aneurysm in the brain can cause a haemorrhagic stroke, so effective treatments for repairing cerebral aneurysms are vital.
"This research is a welcome development. Coiling is a less invasive surgical technique than neurosurgical clipping, but can only be used in a minority of patients whose aneurysms are suitable for this treatment."
The study was mainly funded by the UK Medical Research Council with support from French and Canadian research bodies and the UK Stroke Association.
HOW THE COILING METHOD WORKS
1: Small puncture wound in groin used to feed flexible tube called microcatheter through body to site of aneurysm
2: Platinum coils are pushed through the microcatheter into the aneurysm
3: Once the aneurysm is full of coils, it obstructs the flow of blood. An electrical charge is used to cut the end of the coils from the microcatheter, which is withdrawn. Blood clots around the coils in the aneurysm, preventing it from bursting.