<prompt> Definition of TIA is, patient signs and symptoms resolve by24 hours36 hours48 hours72 hours  <response>: When blood flow is quickly restored, brain tissue can recover fully and the patients symptoms are only transient, this is called a transient ischemic attack TIA. The definition of TIA requires that all neurologic signs and symptoms resolve within 24 h without evidence of brain infarction on brain imaging. Most TIAs last 1 h.Stroke has occurred if the neurologic signs and symptoms last for 24 h or brain infarction is demonstratedRef: Harrison 19e pg: 2559 