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Enhanced phase-sensitive SSFP reconstruction for fat-water separation in phased-array acquisitions
Ozgur Yilmaz1,2, Emine Ulku Saritas1,2,3, Tolga Çukur1,2,3
1Department of Electrical and Electronics Engineering, Bilkent University, Ankara, Turkey.
Journal of Magnetic Resonance Imaging : JMRI
|December 24, 2015
Summary
This study introduces a novel method to enhance fat-water separation in MRI using phased-array coils. The technique improves image quality by reducing noise and increasing accuracy in tissue classification for better diagnostic insights.
Area of Science:
- Magnetic Resonance Imaging
- Medical Imaging Physics
Background:
- Phased-array balanced steady-state free precession (bSSFP) is vital for fat-water separation.
- Spatial variations in phased-array coil sensitivity can degrade phase estimates and tissue classification.
- Existing phase-sensitive SSFP (PS-SSFP) methods struggle with noise in these challenging acquisitions.
Purpose of the Study:
- To develop and validate a method for improving the reliability of phase-sensitive fat-water separation in phased-array bSSFP MRI.
- To address the limitations of current PS-SSFP techniques caused by coil sensitivity variations.
Main Methods:
- Region-growing phase correction was applied to individual coil images using unsupervised seed selection.
- An optimal linear combination of phase-corrected images was used for fat and water signal segregation.
- The method was tested on non-contrast enhanced SSFP angiograms of the lower extremities at 1.5T using an 8-channel coil.
Main Results:
- The proposed method significantly improved fat suppression compared to standard PS-SSFP (P < 0.005).
- Reconstructed water images showed increased similarity to reference IDEAL images (P < 0.005).
- Tissue misclassification was substantially reduced across the imaging volume.
Conclusions:
- The novel method enhances fat-water separation in phased-array MRI by improving phase estimates.
- This leads to more reliable fat suppression and accurate tissue classification.
- The technique offers a valuable improvement for bSSFP imaging with phased-array coils.
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