Transient Ischemic Attack

In brief: A transient ischemic attack, or TIA, is a temporary episode of neurologic dysfunction caused by inadequate blood flow without a completed infarct identified as the cause.

Use in moyamoya disease

Symptoms may include weakness, numbness, facial droop, speech difficulty, vision change, imbalance, or loss of coordination. In moyamoya, episodes can be stereotyped and may occur with dehydration, fever, exertion, crying, or hyperventilation, but a trigger does not make an event harmless. [1]

TIA cannot be reliably distinguished at home from an evolving stroke, seizure, migraine aura, or another emergency. Evaluation may include brain imaging, vascular imaging, perfusion assessment, and review of blood pressure, hydration, anemia, medicines, and other stroke mechanisms.

Clinical detail

Older time-based definitions have been replaced by a tissue-based concept. A brief event can still have diffusion-positive infarction, and a prolonged episode can occasionally resolve without a visible lesion.