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Increasing spoiling efficiency in RF-spoiled gradient echo sequences by averaging of RF phase-cycle-adapted k-spaces
Jochen Leupold1, Jürgen Hennig
1Medical Physics, Department of Radiology, University Hospital Freiburg, Freiburg, Germany. jochen.leupold@uniklinik-freiburg.de
Magnetic Resonance in Medicine
|March 12, 2011
Summary
This study introduces a novel RF-spoiling method for averaged MRI scans. It reduces spoiler gradient moments by leveraging k-space acquisition for artifact cancellation, enhancing signal-to-noise ratio.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Image Reconstruction
- Signal Processing
Background:
- RF-spoiling is crucial in gradient echo sequences to minimize artifacts.
- Averaging multiple acquisitions enhances signal-to-noise ratio (SNR) but can accumulate ghosting artifacts.
- Current methods require significant spoiler gradient moments, impacting scan time and hardware.
Purpose of the Study:
- To develop an improved RF-spoiling technique for averaged MRI.
- To reduce the required spoiler gradient moment in multi-acquisition scans.
- To minimize ghosting artifacts while preserving SNR in averaged images.
Main Methods:
- A novel k-space data acquisition strategy is proposed.
- The averaging process is integrated into the RF-spoiling mechanism.
- Sequence cycle timing is adjusted based on total averages and RF phase-cycling patterns.
Main Results:
- The necessary spoiler gradient moment is reduced by a factor equal to the number of averages.
- Ghost artifacts from individual acquisitions cancel out in the averaged image.
- The method achieves normal averaging of the object with an enhanced SNR.
Conclusions:
- The presented method effectively improves RF-spoiling in averaged MRI.
- It offers a significant reduction in spoiler gradient requirements.
- This technique leads to artifact-free averaged images with improved SNR.
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