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A Method for Determination and Simulation of Permeability and Diffusion in a 3D Tissue Model in a Membrane Insert System for Multi-well Plates
Published on: February 23, 2018
Evaluation of the clinical-diffusion and perfusion-diffusion mismatch models in DEFUSE
Maarten G Lansberg1, Vincent N Thijs, Scott Hamilton
1Stanford Stroke Center, Stanford University Medical Center, Palo Alto, CA 94304, USA. Lansberg@stanford.edu
Stroke
|May 15, 2007
Summary
The perfusion-diffusion mismatch (PDM) model is more accurate than the clinical-diffusion mismatch (CDM) model for selecting acute stroke patients for reperfusion therapy within 3 to 6 hours. PDM identified patients with a significantly higher chance of a favorable clinical response.
Area of Science:
- Neurology
- Radiology
- Medical Imaging
Background:
- The perfusion-diffusion mismatch (PDM) model aids in selecting acute stroke patients for reperfusion therapy.
- The clinical-diffusion mismatch (CDM) model offers a less technically demanding alternative, omitting perfusion-weighted imaging.
Purpose of the Study:
- To evaluate and compare the accuracy of the PDM and CDM models in the DEFUSE dataset.
- To determine which mismatch model best predicts favorable outcomes after reperfusion therapy.
Main Methods:
- The DEFUSE study involved acute stroke patients receiving intravenous tPA between 3-6 hours post-symptom onset.
- MRI scans were acquired before and after treatment to assess PDM and CDM presence.
Main Results:
- PDM was present in 54% and CDM in 62% of patients; agreement between models was not significant (kappa=0.07).
- PDM showed a significant association with favorable clinical response (OR=5.4, P=0.039).
- Optimized PDM criteria yielded a higher odds ratio for favorable response (OR=70, P=0.001) compared to optimized CDM (OR=5.1, P=0.066).
Conclusions:
- The PDM model demonstrates superior accuracy in identifying acute stroke patients likely to benefit from reperfusion therapy within the 3- to 6-hour window.
- PDM is a more reliable predictor of favorable clinical outcomes compared to CDM.
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