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Updated: Jun 10, 2026
07:33
Quantifying Mixing using Magnetic Resonance Imaging
Published on: January 25, 2012
Double-wave-vector diffusion-weighting experiments with multiple concatenations at long mixing times
Marco Lawrenz1, Jürgen Finsterbusch
1Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|July 20, 2010
Summary
Multiple concatenations of diffusion-weighting periods improve double-wave-vector (DWV) MR imaging. This method enhances signal modulation and accuracy for microscopic tissue analysis on whole-body systems.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Biophysics
- Medical Physics
Background:
- Double-wave-vector (DWV) MR sequences offer advanced microscopic tissue analysis.
- Long gradient pulses in DWV experiments reduce signal modulation on whole-body systems.
Purpose of the Study:
- To investigate a multiple concatenation approach for DWV experiments to overcome signal modulation issues.
- To enhance the applicability and reliability of DWV measurements with long mixing times on standard whole-body MR systems.
Main Methods:
- Extension of the tensor equation to accommodate multiple concatenations of diffusion-weighting periods.
- Validation using Monte-Carlo simulations to approximate signal behavior with typical whole-body gradient pulse durations.
Main Results:
- The multiple concatenation model accurately approximates observed signals for standard gradient pulse durations.
- Anisotropy measures derived from this model show good accuracy.
- Increased signal modulation is achieved by using shorter gradient pulses with multiple concatenations.
Conclusions:
- The multiple concatenation approach effectively ameliorates signal modulation problems in DWV experiments.
- This method improves the accuracy and reliability of DWV measurements on whole-body MR systems.
- Enables more robust microscopic tissue characterization using standard clinical MRI scanners.
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