A simple blood test could soon help doctors to identify patients who are having a stroke much more quickly.
The test is undergoing clinical trials
A report in New Scientist magazine says a test, made by US company Biosite, can diagnose stroke in just 15 minutes.
The test analyses blood to see if it contains proteins from the brain, released during strokes.
While further research is needed, the test could enable doctors to diagnose and treat stroke faster reducing the risks of long-term damage.
It comes as a study in the UK suggests many people who suffer strokes do not get the right treatment quickly enough.
Doctors at Derriford Hospital in Plymouth surveyed 160 people. These included people who had had strokes, people who were at risk of stroke, nurses and members of the public.
They found that some of the patients who had had strokes had waited up to six days before seeking medical help. The average waiting time was 30 minutes.
In 80% of cases, the family doctor was called instead of an ambulance, potentially delaying vital treatment.
Writing in the Journal of Neurology, Neurosurgery and Psychiatry, the doctors said the findings highlighted the need to ensure people knew what to do in the event of a stroke.
"A campaign should target people at risk, reinforcing the diagnosis of stroke and access to medical services," they said.
Strokes are one of the most common causes of death and disability.
Over 80% are caused by a blood clot blocking an artery in the brain. Others are caused by ruptured blood vessels.
A quarter of people who have a stroke die while survivors are often left with permanent brain damage.
Diagnosing a stroke can be difficult because the symptoms vary and sometimes resemble those of other conditions.
CT scans are good at spotting bleeds but are far less reliable when it comes to identifying the early stages of strokes.
"The lack of a rapid diagnostic for stroke is a huge problem," Dr Daniel Laskowitz, a neurologist at Duke University Medical Center in North Carolina and a consultant for Biosite told the magazine.
Quicker diagnoses could enable doctors to give patients clot dissolving drugs that can reduce brain damage if given within three hours of a stroke.
The lack of a fast, accurate test for stroke means many patients who could benefit from these drugs do not get them.
Dr Laskowitz believes the Biosite test could be the answer. The company is about to start a large clinical trial in 15 medical centres in the US.
"In theory, this could go into ambulances," said Dr Laskowitz. "Every emergency room can have it."
The test would have to pass clinical trials before it could be licensed for use in hospitals.