Imaging of acute stroke: CT and/or MRI.

Acute ischemic stroke is now clearly recognized as a medical emergency. As such diagnosis has to be done quickly and in a precise way during the therapeutic window. Both computed tomography and magnetic resonance imaging are tools that can adequately demonstrate ischemia really very early on. MRI using diffusion techniques has a much higher sensitivity for acute lesions but its implementation has not been unproblematic due to initial resistance and some technical problems. Thus, very often CT is still preferred with MR used for situations where the answer given is not sufficient as well as for follow-up of lesions. However, the parallel development of new therapeutic strategies have rendered the precision of the tools more and more sophisticated and their combined use can help to improve patient outcomes in ways never imagined previously. No matter which technique is used, be it alone or in combination, the idea is to speed up and optimize management in order to provide early revascularization and reperfusion.