Stroke and ischemia.

With the introduction of diffusion imaging the diagnosis and acute stroke can be made within minutes of clinical onset. In combination with perfusion imaging, tissue viability can be assessed. The etiology of ischemia can in most cases be investigated by MR angiography. The current applications of these techniques are reviewed, and pitfalls as well as problems in the diagnosis of acute stroke are discussed. With the availability of these techniques, patients can almost instantaneously be approved for pharmacotherapy and monitored and thus clinical outcome potentially can be improved tremendously.