Q. What is a mini-stroke and how is it different from a stroke?
A. “Mini-stroke” is a term commonly used for a transient ischemic attack (TIA), which has the same signs and symptoms as a stroke, but usually lasts only minutes to hours and leaves no detectable damage in the brain that can be seen with brain imaging. Symptoms include sudden weakness or numbness in the face, arm, or leg — the face may appear asymmetrical or one arm may droop — slurred or altered speech, blindness or doubled vision, and dizziness or loss of balance.
TIA has the same basic cause as an ischemic stroke (the most common type of stroke). Blood flow in an artery in the brain is blocked, reducing oxygen flow to part of the brain. Lee Schwamm, director of stroke services at Massachusetts General Hospital, uses the analogy of a kink in the hose leading to your sprinkler: If it straightens out quickly, there’s no noticeable effect on your lawn. If the water is blocked for too long, you get a brown patch on the grass.
Even if a mini-stroke leaves no permanent damage, it’s a major warning sign. “I sometimes call it ‘the Stroke of Christmas Future’,” Schwamm says. According to the National Stroke Association, up to 40 percent of people who have a TIA will eventually have a stroke — 5 percent within two days, and 10 to 15 percent within three months. Schwamm advises seeking immediate medical attention; treatment focuses on lifestyle changes or medication to prevent a stroke.