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A Magnetic Resonance Imaging Protocol for Stroke Onset Time Estimation in Permanent Cerebral Ischemia
Published on: September 16, 2017
Magnetic resonance diffusion-perfusion mismatch in acute ischemic stroke: An update
1Feng Chen, Yi-Cheng Ni, Department of Radiology, Catholic University of Leuven, Campus Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium.
World Journal of Radiology
|April 3, 2012
Summary
Magnetic resonance perfusion-diffusion mismatch (PDM) helps identify stroke tissue at risk. While PDM shows promise for predicting treatment benefits and outcomes, further research is needed to confirm its effectiveness in guiding thrombolytic therapy.
Area of Science:
- Neuroimaging
- Cerebrovascular Diseases
- Medical Diagnostics
Background:
- Magnetic resonance perfusion-diffusion mismatch (PDM) is a key concept in evaluating acute stroke.
- It approximates the extent of tissue at risk.
- Recent findings suggest PDM may not perfectly delineate the ischemic penumbra.
Purpose of the Study:
- To review the applications and limitations of PDM in acute stroke.
- To discuss efforts to optimize PDM and alternative methods for defining the ischemic penumbra.
- To examine the relationship between PDM patterns and clinical outcomes in stroke patients.
Main Methods:
- Review of existing literature on perfusion-diffusion mismatch in stroke.
- Analysis of PDM's role in patient selection for stroke treatment.
- Evaluation of PDM as a surrogate marker for stroke outcomes.
Main Results:
- Patients with PDM often show improved reperfusion, reduced infarct growth, and better clinical outcomes.
- However, the benefit of thrombolytic therapy when selected by PDM remains unclear.
- Early diffusion-weighted imaging may overestimate the infarct core, while perfusion imaging may overestimate the penumbra.
Conclusions:
- PDM is a valuable tool for assessing stroke, but its limitations require optimization.
- Alternative imaging strategies are being investigated to more accurately define the ischemic penumbra.
- Larger cohort studies are necessary to validate the PDM hypothesis and its clinical utility in guiding stroke treatment.
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