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Updated: Aug 31, 2025
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High-speed Particle Image Velocimetry Near Surfaces
Published on: June 24, 2013
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Velocity-selective excitation: Principles and applications
Zungho Zun1, Taehoon Shin2,3,4
1Department of Radiology, Weill Cornell Medicine, New York, New York, USA.
NMR in Biomedicine
|August 22, 2022
Summary
Velocity-selective (VS) excitation offers novel MRI contrast based on spin motion. This review details VS excitation principles and its clinical uses in angiography and arterial spin labeling.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Medical Physics
- Biomedical Engineering
Background:
- Velocity-selective (VS) excitation is an advanced MRI technique.
- It generates image contrast by leveraging the motion of spins.
- Understanding its principles is crucial for clinical applications.
Purpose of the Study:
- To elucidate the fundamental principles of VS excitation.
- To review its practical implementation in MRI pulse sequences.
- To demonstrate its utility in various clinical applications.
Main Methods:
- Review of generalized excitation k-space formalism.
- Analysis of practical VS excitation pulse sequences (sinusoidal, sinc-shaped velocity profiles).
- Demonstration of applications in arterial spin labeling and angiography.
Main Results:
- Established a Fourier relationship between sequence parameters and excitation profiles for moving spins.
- Identified practical VS pulse sequences for controlled velocity profiles.
- Showcased VS excitation's role in saturation/inversion-based ASL and black/bright-blood angiography.
Conclusions:
- VS excitation provides a powerful method for motion-based contrast in MRI.
- Its application in ASL and angiography is well-supported by k-space formalism.
- Practical considerations for implementation and system errors are discussed.
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