RSNA News - September 2004

Radiologists Play More Prominent Role in Stroke Triage

The CT scan (left) in this patient with acute hemiplegia is relatively unremarkable. The CT angiogram (middle) shows an occluded right middle cerebral artery (MCA) and the CT perfusion image (right) shows a large area of very low cerebral blood volume in all of the right MCA territory. Images courtesy of Vincent P. Mathews, M.D.

Acute left hemisphere stroke, diffusion-perfusion mismatch on MR image. Although there is only a small ischemic lesion on DWI (arrow), there is a much larger region at risk (dotted line) shown by PWI (mean transit time map, longer times in red). The goal of urgent treatment is to quickly restore blood flow to prevent further injury within the tissue at risk. Image courtesy of Howard A. Rowley, M.D.