Methodology: 4/5
Usefulness: 3.5/5

Thomalla G, et al. Lancet. 2020 Nov 14;396(10262):1574-1584

Question and Methods: The authors evaluated the role of perfusion-imaging facilitated thrombolysis in strokes of unknown duration by way of a systematic review and individual patient data meta-analysis.
Findings: Perfusion-imaging facilitated thrombolysis improved neurological outcomes (mRS 0-1 at 90 days: 47 vs 39% [OR 1.49, 95% CI 1.10-2.03, P = 0.011] for tPA vs placebo).
Limitations: Trials reviewed were all stopped early, possibly introducing bias and 85% of perfusion imaging used was MRI, limiting applicability to a Canadian context.

Interpretation: Stroke care is evolving and becoming more nuanced; perfusion-imaging is likely to disrupt traditional time cut-offs for thrombolysis in the near future. 

By: Dr. Doran Drew

For all our other stroke related posts check out this link.


  • Hans Rosenberg

    Dr. Rosenberg is an emergency physician at the Ottawa Hospital, assistant professor at the University of Ottawa, and Director of the Digital Scholarship and Knowledge Dissemination Program.