Abstract
Purpose
To determine the evolution of the ischemic lesion volumes in a population treated with tissue plasminogen activator (t‐PA), MRIs were performed before treatment and 24 hours later; final infarct size was evaluated 60 days later.
Materials and Methods
A total of 42 patients with hemispheric stroke were recruited for a thrombolytic study. Intravenous t‐PA was given after MRI within the first seven hours after stroke onset. Volumes were evaluated on day 0 and day 1 with diffusion‐weighted imaging (DWI), on day 60 with T2‐weighted imaging (T2WI), and recanalization was assessed based on day 1 MR angiography (MRA).
Results
Lesion volume increased between day 0 and day 1, and decreased between day 1 and day 60. It was lower in the group of patients with recanalization on day 1 MRA.
Conclusion
Volume analysis emphasizes the effectiveness of recanalization as a predictive factor for better outcome, based on final infarct size. The decrease in lesion volumes between day 1 and day 60 suggests that other factors leads to overestimation of day 1 abnormal diffusion volume. This could explain the delayed partial reversibility of the DWI abnormality. J. Magn. Reson. Imaging 2005;22:23–28. © 2005 Wiley‐Liss, Inc.