Stroke

Canadian Stroke Network

The Canadian Stroke Network – one of Canada’s Networks of Centres of Excellence – is a unique collaborative effort that brings together researchers, students, government, industry and the non-profit sector. At present, the Network involves more than 100 researchers at 24...

Learn more about the Canadian Stroke Network.

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Stroke is the leading cause of disability worldwide. Approximately 300,000 Canadians are living with the affects of a stroke.

A stroke occurs when blood vessel bringing oxygen and nutrients to the brain bursts, referred to as a hemorrhagic stroke, or is clogged by a blood clot, referred to as an ischemic stroke (approximately 80% of strokes are ischemic and 20% are hemorrhagic). This results in a sudden loss of brain function, since the brain is deprived of blood, causing damage to the brain as cells die. The type of stroke, severity and areas of the brain damaged will determine the level of long-term disability, such as paralysis, loss of communication skills (Aphasia), vision problems, loss of memory and emotional challenges including depression.

The symptoms of stroke appear suddenly, over a few minutes or hours or at most a couple of days. Individuals should be able to recognize the five main symptoms of stroke and seek immediate medical attention if any of these symptoms occur:

• sudden paralysis or numbness of the face, arm, or leg (usually on only one side of the body)
• sudden loss of speech or trouble understanding speech
• sudden loss of vision (often in one eye only) or double vision
• sudden dizziness or loss of balance or coordination
• sudden severe and unusual headache (often described as "the worst headache of my life" that starts suddenly) with no known cause

Preventing brain damage, disability, and aiding recovery depends on getting treatment in the first few hours following a stroke. Brain cells that are deprived of blood flow and oxygen for even just a few minutes will die.

Getting emergency medical assistance as soon as you experience symptoms of stroke is critical because there are treatments that may be given to help restore blood flow to the brain, prevent further tissue damage in the brain, or prevent recurrent strokes. Studies show that as few as 2% of stroke patients arrive at the hospital within the first 3 hours of a stroke to be eligible for potential treatment with clot-dissolving medications.