Abstract
Current diagnostic criteria, as reported in the International Classification of Headache Disorders, Second Edition (ICHD-II) (1), for headache attributed to transient ischemic attack (TIA) are (A) any new acute headache fulfilling criteria C and D; (B) focal neurological deficit of ischemic origin lasting less than 24 hours; (C) development of headache simultaneously with onset of focal deficits; and (D) resolution of headache within 24 hours. Diagnostic criteria were based on the classic definition of TIA as a sudden, focal neurologic deficit that lasts for less than 24 hours, is presumed to be of vascular origin and is confined to an area of the brain or eye perfused by a specific artery (2).
In 2009, however, the American Heart Association/American Stroke Association Scientific Committee endorsed and recommended a new definition of TIA (3). The need for a new definition was driven by the evidence that many ischemic episodes with symptoms lasting less than 24 hours were associated with new infarction on neuroimaging. In fact, the 24-hour criterion was arbitrary as at the time of the classic definition no neuroradiological techniques were available and it was hypothesized that a transient deficit was not caused by a permanent brain injury. According to the new definition, a TIA is defined as a transient episode of neurological dysfunction caused by focal brain, spinal cord or retinal ischemia, without acute infarction. To avoid arbitrary time limits that are associated with stroke or TIA, the committee removed any reference to a time frame from the definition. To diagnose a TIA, this new definition requires brain imaging, and to facilitate consistency within stroke and TIA data, the committee recommends MRI as the preferred imaging modality.
Updated diagnostic criteria for headache attributed to transient ischemic attack
