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Frequency response of multipoint chemical shift-based spectral decomposition
Ethan K Brodsky1, Venkata V Chebrolu, Walter F Block
1Department of Radiology, University of Wisconsin, Madison, Wisconsin 53705-2275, USA. brodskye@cae.wisc.edu
Journal of Magnetic Resonance Imaging : JMRI
|October 1, 2010
Summary
This study presents a framework for analyzing multipoint chemical shift imaging techniques. The frequency response of these species separation methods is linear and can be fully characterized by magnitude and phase curves.
Area of Science:
- Magnetic Resonance Imaging
- Spectroscopy
Background:
- Multipoint chemical shift based species separation techniques are crucial for analyzing complex biological samples.
- These methods involve acquiring images at multiple echo times and employing maximum likelihood estimation for signal decomposition.
Purpose of the Study:
- To establish a framework for characterizing the frequency response of multipoint chemical shift based species separation techniques.
- To analyze the linear transform properties of these decomposition methods.
Main Methods:
- Acquisition of complex images at multiple echo times.
- Application of maximum likelihood estimation for signal decomposition.
- Numerical and experimental modeling to determine frequency response magnitude and phase.
Main Results:
- Development of simple expressions to describe the frequency response for various input signals.
- High agreement observed between numerical modeling and experimental results.
- Demonstration of the linear nature of chemical shift based species separation.
Conclusions:
- Chemical shift based species separation is a linear process fully described by frequency response magnitude and phase.
- The periodic nature of the frequency response impacts the robustness of techniques addressing field inhomogeneity.
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