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Diffusion Tensor Magnetic Resonance Imaging in Chronic Spinal Cord Compression
Published on: May 7, 2019
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Low-rank plus sparse compressed sensing for accelerated proton resonance frequency shift MR temperature imaging.
Zhipeng Cao1,2,3, John C Gore1,2,3, William A Grissom1,2,3
1Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee.
Magnetic Resonance in Medicine
|February 2, 2019
Summary
A new method improves MR thermography reconstruction for MRI heating and MR-guided focused ultrasound. This technique enhances temperature accuracy and enables faster imaging with compressed sensing.
Area of Science:
- Medical Physics
- Biomedical Imaging
- Magnetic Resonance Imaging
Background:
- Compressed sensing (CS) is crucial for accelerating dynamic MRI scans.
- Proton Resonance Frequency (PRF) shift thermography requires accurate temperature reconstruction.
- Existing CS methods for PRF thermography have limitations in accuracy and acceleration.
Purpose of the Study:
- To develop an improved multichannel CS reconstruction for MR PRF shift thermography.
- To enhance the evaluation of MRI-induced RF heating.
- To improve temperature monitoring during MR-guided high intensity focused ultrasound (MRgFUS) procedures.
Main Methods:
- A novel CS reconstruction method was developed, enforcing joint low rank and sparsity on complex difference domain PRF data.
- The method was validated on four retrospectively undersampled dynamic PRF datasets.
- Performance was compared against L1+TV and conventional L+S CS reconstruction approaches.
Main Results:
- The proposed method achieved a 3.6x acceleration ratio with superior temperature accuracy compared to existing methods.
- For RF heating evaluation, RMS error was 12% (proposed) vs. 19% (L+S) and 17% (L1+TV).
- In vivo MRgFUS thalamotomy showed peak temperature errors of 19% (proposed) vs. 31% (L+S) and 35% (L1+TV).
Conclusions:
- The complex difference-based low rank and sparse model improves compressibility for dynamic PRF thermography.
- The proposed multichannel CS reconstruction enables high acceleration factors for MRgFUS and RF heating evaluation.
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