Imaging funzionale per diffusione (DWI) e ischemia cerebrale in fase acuta: Potenzialità diagnostiche e confronto con metodiche convenzionali

Stroke is the third leading cause of death and is a major cause of long-term disability. Neuroprotective treatment within a 4-hour «therapeutic window» has proved highly efficacious in reducing morbility and mortality in animal model. It is with this background that the need for emergent diagnosis and therapy of acute stroke in strongly suggested. Computed tomography (CT) shows the parenchymal changes of acute stroke too late to be helpful, and its role has been primarily to evaluate the possibility of intracerebral or subarachnoid hemorrhage. While conventional magnetic resonance (MR) imaging can demonstrate parenchymal abnormalities 4–6 hours after ischemia, newer techniques such as diffusion-weighted MR imaging (DWI) hold promise that a diagnosis of ischemia can be made within minutes after the acute event. In this article compares different aspects of hyperacute cerebral ischemia depicted at diffusion-weighted imaging before infarction is depicted at conventional MR or CT scans. DWI techniques may improve stroke diagnosis and may contribute to advances in treatment.