MRI predicts area of increased plasminogen activation in permanent focal cerebral ischemia.

To determine if MRI can predict intracerebral plasminogen activation after focal cerebral ischemia (FCI), ischemic regions detected by MRI after 48 h of permanent FCI in rats were compared with areas of increased plasminogen activation, defined by histological zymography after 72 h of ischemia. The overlap between areas of MRI alterations (64.5% +/- 5.4% of total ischemic hemisphere) and areas with increased plasminogen activation (62.2% +/- 3.6%) was significant for the hemisphere (p < 0.001), the cortex (p < 0.05), and the basal ganglia (p < 0.05). Thus, MRI can predict the extent of increased plasminogen activation, which may play a role in BBB-mediated post-ischemic brain edema and secondary hemorrhage.