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S5FP: spectrally selective suppression with steady state free precession
J A Derbyshire1, D A Herzka, E R McVeigh
1Laboratory of Cardiac Energetics, National Heart, Lung and Blood Institute, National Institutes of Health, DHHS, Bethesda, MD 20892-1061, USA. jad11@nih.gov
Magnetic Resonance in Medicine
|September 13, 2005
Summary
A novel Spectrally Selective Suppression with SSFP (S(5)FP) method effectively suppresses fat signals in MRI scans. This technique maintains water signal integrity and contrast with minimal impact on imaging speed.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Pulse Sequence Optimization
Background:
- Steady-State Free Precession (SSFP) is a widely used MRI pulse sequence.
- Achieving spectral fat suppression without compromising image quality or scan time is a persistent challenge in MRI.
Purpose of the Study:
- To introduce and validate a new method, Spectrally Selective Suppression with SSFP (S(5)FP), for effective fat signal suppression in MRI.
- To demonstrate that S(5)FP leverages the inherent spectral properties of SSFP for targeted signal attenuation.
Main Methods:
- The S(5)FP method utilizes SSFP at TE = TR/2 to partition magnetization into phase-opposed components.
- One component is Z-stored while the other is selectively suppressed using gradient crushing and RF spoiling.
- Validation was performed using computational simulations, phantom studies, and human subject imaging.
Main Results:
- S(5)FP achieved significant attenuation of fat signals in MRI.
- Water signals remained largely unaffected, preserving normal SSFP image contrast.
- The method introduced less than 10% temporal overhead, minimizing reduction in temporal resolution.
Conclusions:
- S(5)FP is an effective technique for spectral fat suppression in MRI.
- The method offers a good balance between fat suppression efficacy, water signal preservation, and minimal impact on scan time.
- S(5)FP presents a valuable advancement for MRI applications requiring robust fat suppression.
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