Stroke

Strokes, or brain attacks, are a major cause of death and permanent disability. They occur when blood flow to a region of the brain is obstructed and may result in death of brain tissue.

There are two main types of stroke: ischemic and hemorrhagic. Ischemic stroke is caused by blockage in an artery that supplies blood to the brain, resulting in a deficiency in blood flow (ischemia). Hemorrhagic stroke is caused by the bleeding of ruptured blood vessels (hemorrhage) in the brain.

During ischemic stroke, diminished blood flow initiates a series of events (called ischemic cascade) that may result in additional, delayed damage to brain cells. Early medical intervention can halt this process and reduce the risk for irreversible complications.

Strokes, or brain attacks, are medical emergencies that require immediate medical attention. Warning signs of stroke include the following:
 

• Sudden numbness or weakness, especially on one side of the body

• Sudden confusion

• Sudden vision problems in one or both eyes

• Sudden difficulty walking, dizziness, loss of balance or coordination

• Sudden, severe headache with no known cause

• Sudden difficulty speaking or understanding speech