Outcome of transient ischaemic attacks and stroke.

Much of the published data concerning the outcome in patients with transient ischaemic attacks and stroke was produced before the development of computerised tomography, and when the risk factors for cerebrovascular disease were different in quality and quantity. Outcome data also depend on the definition of the original disorders, which remain controversial and are often poorly described. Recent advances in laboratory diagnosis, such as imaging of the brain and extra- and intra-cranial blood vessels, have also made definition more complex. Strokes due to carotid artery stenosis differ in outcome from those due to cardiac embolism; the most benign group is that of lacunar strokes. Recent trials indicate a more serious prognosis for patients with carotid stenosis than previously believed, although these data are affected by referral bias. Outcome data will need to be updated in the future as more becomes known about the aetiology and pattern of cerebrovascular disease.