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Role of diffusion and perfusion MRI in selecting patients for reperfusion therapies

Mikayel Grigoryan1, Christie E Tung, Gregory W Albers

  • 1Stanford Stroke Center, Department of Neurology and Neurological Sciences, Stanford University Medical Center, 780 Welch Road, Palo Alto, CA 94304, USA. mikayel@gmail.com

Neuroimaging Clinics of North America
|June 7, 2011
PubMed

Insights

Expanding the treatment window for acute ischemic stroke is crucial. Advanced MRI techniques can identify salvageable brain tissue, potentially enabling thrombolytic therapy beyond the current 4.5-hour limit for more stroke patients.

Area of Science:

  • Neurology
  • Radiology
  • Emergency Medicine

Background:

  • Ischemic stroke poses a significant threat, with salvageable brain tissue (ischemic penumbra) diminishing over time.
  • Current treatment with intravenous alteplase is limited to 4.5 hours post-stroke symptom onset.
  • A wider therapeutic window could benefit a larger patient population.

Purpose of the Study:

  • To explore the potential of advanced MRI techniques in identifying the ischemic penumbra.
  • To assess the feasibility of extending thrombolytic treatment beyond 4.5 hours for acute ischemic stroke.

Main Methods:

  • Utilizing advanced MRI to differentiate between irreversibly damaged brain tissue (infarct core) and the potentially salvageable ischemic penumbra.
  • Developing patient selection strategies based on penumbral imaging for clinical trials.

Main Results:

  • Penumbral imaging demonstrates promise in identifying viable brain tissue at risk.
  • Advances in imaging technology may facilitate patient selection for extended treatment windows.

Conclusions:

  • MRI-based penumbral imaging holds significant potential for optimizing acute ischemic stroke treatment.
  • Further research, including phase III trials, is warranted to establish extended thrombolytic therapy protocols.

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