OAK BROOK, Ill -- February 9, 2009 -- Some patients who suffer an ischaemic stroke may benefit from a clot-busting drug 9 or more hours after the onset of symptoms, according to a study published online in the journal Radiology.
In the retrospective study, William A. Copen, MD, Advanced Magnetic Resonance Neuroimaging, Massachusetts General Hospital (MGH), Boston, Massachusetts, and colleagues analysed the test results of 109 ischaemic stroke patients at MGH. The testing methods included perfusion magnetic resonance imaging (MRI) and diffusion MRI.
"Comparing the lesions that we see in these 2 MR images reveals which areas of the brain are threatened by a lack of blood flow, but could still be salvageable," said Dr. Copen. "A mismatch between the lesions suggests that a patient might still benefit from thrombolytic therapy."
Most patients in the study with blockage in a proximal artery continued to demonstrate a diffusion-perfusion mismatch between 9 and 24 hours after the onset of their strokes.
"Patients who have a mismatch have been successfully treated up to 9 hours after stroke onset, which is already much longer than the guidelines allow," Dr. Copen said. "Our findings suggest a need for a clinical trial to measure the effectiveness of thrombolytic therapy more than 9 hours after the onset of an ischaemic stroke."
SOURCE: Radiological Society of North America
E-Mail this DGNews to a colleague
