Strokes can cause brain damage within 3 minutes , scientist reported , casting doubt on the common public perception that all stroke can be medically treated within 3 hours.
The findings shows that prevention is the best strategy for one of the top killers of the developed world, said Dr Tim Murphy, a neuroscientist at the University of British Columbia in Vancouver.
“There’s a lot of thinking, if I’ve had a stroke I’ve got to get to the hospital and I’ll be OK as long as I get there in 3 hours”, said Murphy.
Some people can be helped within that time, but “I’m saying there are structural that happen very early on, and so the best thing is to manage risk factors and alter lifestyle”, Murphy said.
About 80% of stroke are ischemic and are caused by a clot blocking blood flow to the brain, according to the Heart and Stroke Foundation Canada, which helped to fund the research.
Such stroke are most treated by clot-busting drugs (trombolytic therapy), if given in hospital within 3 hours.
About 80% of stroke are ischemic and are caused by a clot blocking blood flow to the brain, according to the Heart and Stroke Foundation Canada, which helped to fund the research.
Such stroke are most treated by clot-busting drugs (trombolytic therapy), if given in hospital within 3 hours.
“But the reality is, not everyone is a candidate for clot-busting drugs, they don’t always work”, said Murphy.
Murphy said, researchers induced stroke in laboratory mice by blocking blood flow to the brain of the animals. At the same time, they used a high tech imaging technique, two-photon excitation microscopy, to create a “movie” that revealed the impact.
The mice experienced a “massive electrical discharge, called ischemic depolarization, a wave of activity that spreads across the brain”, and then experienced swelling in the brain nerve cells, called neurons, said Murphy.
Normal connections between such cells are “a beautiful chain of wiring between one neuron and another that look like trees with elegant branches”, said Murphy.
“After a stroke, they’ll look like sausages (or) like beads on a string and there’s no neuronal activity.”
Normal connections between such cells are “a beautiful chain of wiring between one neuron and another that look like trees with elegant branches”, said Murphy.
“After a stroke, they’ll look like sausages (or) like beads on a string and there’s no neuronal activity.”
Murphy said research shows quickly replacing the blood flow to the lab mice can reverse most nerve-cell damage, but some six percents of the connections can never return to normal.
The three-minute window before brain damage from a stroke doesn’t give people enough time to even call for help, said Murphy.
“We can’t treat in three minutes.”
“We can’t treat in three minutes.”
But the findings may help people undergoing surgery that can trigger ischemic stroke, he said because the three-minute window shows the urgent need for preventive measures.
Risk factors for stroke include smoking, being overweight, physical inactivity, alcoholism, diabetes, stress and cholesterol, said the foundation.-AFP
Risk factors for stroke include smoking, being overweight, physical inactivity, alcoholism, diabetes, stress and cholesterol, said the foundation.-AFP
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