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Low rank off-resonance correction for double half-echo k-space acquisitions
Mark Bydder1, Fadil Ali1, Andres Saucedo1
1Department of Radiological Sciences, David Geffen School of Medicine, University of California Los Angeles, CA, USA.
Magnetic Resonance Imaging
|September 16, 2022
Summary
This study presents a model-based method to correct off-resonance artifacts in double half-echo MRI. The technique effectively reduces pixel shifts and blurring, improving image quality in low bandwidth sodium imaging.
Area of Science:
- Medical Imaging
- Magnetic Resonance Imaging (MRI)
- Spectroscopy
Background:
- Double half-echo k-space acquisitions reduce echo-times using center-out readouts.
- This acquisition method is sensitive to off-resonance effects, causing pixel shifts.
- Off-resonance artifacts degrade image quality in MRI.
Purpose of the Study:
- To develop and demonstrate a model-based approach for correcting off-resonance in double half-echo MRI.
- To mitigate pixel shifts and blurring caused by off-resonance.
- To improve image quality in low bandwidth sodium imaging.
Main Methods:
- A model-based technique was applied to correct off-resonance.
- The method involves demodulating the k-space signal with a constant off-resonance term per slice.
- Center-out readouts in forward and reverse directions were utilized.
Main Results:
- The proposed method effectively removes pixel shifts caused by off-resonance.
- A significant reduction in image blurring was observed.
- Successful demonstration on phantom and in vivo low bandwidth sodium imaging datasets.
Conclusions:
- Model-based off-resonance correction is effective for double half-echo MRI.
- The technique enhances image clarity and reduces artifacts.
- This approach shows promise for improved low bandwidth sodium imaging.
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