Diagnostic radiology of apoplexy - imaging of cerebral ischemia

The recent enhancements achieved in CT and MR imaging techniques have launched a debate about the techniques preferrably to be applied for diagnostic evaluation of acute cerebral stroke. At present, CT still is the modality of choice for primary evaluation of cerebral ischemia, due to relative cost-effectiveness, high availability, and the capability to reliably differentiate ischemia from hemorrhage. MRI on the other hand is superior to CT in detecting and imaging the infarction area within the first few hours, especially if the technique of diffusion-weighted sequencing is applied. Current research focuses on determining whether MRI with perfusion and diffusion-weighted sequencing will yield images distinctly showing the penumbra on the one hand, and the damaged brain tissue on the other. It remains to be seen whether improved tomographic imaging will lead to novel approaches for therapy. (orig./CB)