MRI spots patients prone to poststroke bleeds

Contrast-enhanced MRI reliably predicts whether acute stroke patients receiving intravenous tPA treatment are particularly susceptible to intracranial hemorrhage, according to a study presented at the American Society of Neuroradiology meeting in San Diego.

Dr. David J. Mikulis, an associate professor of neuroradiology at Toronto Western Hospital, reported that the presence of blood-brain barrier breakdown identified with postgadolinium T1-weighted spin-echo imaging produced 100% positive and negative predictive values for 10 of 24 patients who developed hemorrhagic transformation.

Hyperintensities were absent in all 14 patients without intracranial bleeding but were seen in five of 10 patients who developed hemorrhage in the week following treatment.

Studies presented by Mikulis and other researchers at the meeting added weight to growing evidence demonstrating the power of MRI and CT to determine when tPA thrombolysis should be attempted beyond the traditional three-hour treatment window.