Transient Ischemic Attack

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Transient Ischemic Attack (TIA), medical term for a ministroke, a sudden loss of function in one region of the brain. Symptoms may include double vision or temporary loss of vision, speech difficulties, vomiting, loss of sensation and movement on one side of the body, dizziness, unsteadiness, and loss of memory. Loss of consciousness is rare. Symptoms usually reach a peak within seconds and last for minutes or hours. Recovery is complete, but TIAs tend to recur.

A TIA is caused by the obstruction of small blood vessels by tiny blood clots or, less often, by reduced blood supply to the brain associated with diseases of the heart or blood vessels, such as narrowing of the arteries due to atherosclerosis. Aspirin, because of its anticlotting properties, may reduce the risk of TIAs in some patients. Other cases may be helped by an operation known as carotid artery endarterectomy, used to clear blockage of the carotid artery in the neck.

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