Free-breathing liver fat quantification using a multiecho 3D stack-of-radial technique

Area of Science:

• Medical Imaging
• Radiology
• Hepatology

Background:

• Nonalcoholic fatty liver disease (NAFLD) diagnosis relies on invasive liver biopsy.
• Current noninvasive MRI fat quantification methods require breath-holding, limiting efficiency.
• There is a need for faster, noninvasive techniques for liver fat assessment.

Purpose of the Study:

• To develop and evaluate a novel free-breathing 3D stack-of-radial (FB radial) MRI technique for liver fat quantification.
• To compare the accuracy of the FB radial technique against established breath-hold MRI methods.

Main Methods:

• Phantoms and 11 healthy subjects were scanned at 3 Tesla.
• Proton-density fat fraction (PDFF) was measured using FB radial MRI (with and without acceleration).
• FB radial PDFF was compared to breath-hold single-voxel MR spectroscopy (SVS) and breath-hold 3D Cartesian MRI using regression and Bland-Altman analysis.

Main Results:

• FB radial MRI demonstrated high correlation (ρ > 0.998, ρc > 0.995) and minimal differences (<2.2%) with BH SVS in phantoms.
• FB radial MRI showed excellent correlation (ρ > 0.999, ρc > 0.998) and minimal differences (<0.6%) with BH Cartesian MRI in phantoms.
• In vivo liver and abdomen scans showed significant correlation (ρ > 0.986, ρc > 0.985) and small differences (<1%) with BH SVS, and high correlation (ρ > 0.996, ρc > 0.995) and small differences (<0.9%) with BH Cartesian MRI.

Conclusions:

• The novel FB radial technique enables accurate 3D liver fat quantification.
• This free-breathing MRI method can be performed in 1-2 minutes.
• The technique offers a promising noninvasive alternative for NAFLD assessment.