Recent laboratory and clinical research has changed the fatalist view that
little can be done for patients suffering stroke, and has generated a new
paradigm in which rapid evaluation allows patients to be selected for novel
treatments that can reduce mortality and long-term disability. The
widespread introduction of computed tomography (CT) in the 1970s
revolutionized stroke diagnosis, but the recent development and deploy￾ment of multidetector CT (MDCT), along with increased computing
power and synchronized power injectors, have added a new dimension to
CT in which more detailed anatomic imaging can be combined with an
ability to explore the physiology of the cerebral vasculature. This enhanced
ability to perform perfusion imaging has resulted in CT becoming a
widely available imaging technique that can depict the extent of cerebral
ischemia and so provide one of the essential components of the rapid
assessment required for the improved management of patients with stroke