The Value of Apparent Diffusion Coefficient Maps in Early Cerebral Ischemia

Prediction of the regions of the ischemic penumbra that are likely to progress to infarction is of great clinical interest. Whether lowered apparent diffusion coefficient (ADC) values were present in the ischemic penumbra of patients presenting with acute ischemic stroke and were specific to regions of the penumbra that proceeded to infarction was investigated. Nineteen patients with hemispheric stroke of less than 6 hours' onset and with acute scans showing a perfusion lesion greater than a diffusion lesion (ischemic penumbra) were studied. Scans also were performed subacutely (days 3 to 5) and at outcome (day 90). The outcome scan was used to identify regions of the penumbra that proceeded to infarction. The ADC ratios were significantly reduced (P