Cerebral perfusion imaging in acute stroke.

Herein, the author discusses four perfusion technologies, including the diffusible tracer methods-xenon-enhanced computed tomography (CT) and single photon emission CT with various radioisotopes-and the nondiffusible tracer techniques-CT perfusion and magnetic resonance (MR) perfusion and diffusion. The methods for and important issues in the performance of each technique are presented, along with the accuracy of the data acquired with each technique, as demonstrated with experimental studies. In addition, the use of each technique in the evaluation of patients with acute stroke and their relative advantages and disadvantages are presented.