Related Experiment Video
Updated: Dec 20, 2025
Fat-Water Phantoms for Magnetic Resonance Imaging Validation: A Flexible and Scalable Protocol
Published on: September 7, 2018
Free-Breathing Volumetric Liver and Proton Density Fat Fraction Quantification in Pediatric Patients Using
Xiaodong Zhong1, Houchun H Hu2,3, Tess Armstrong4
1MR R&D Collaborations, Siemens Healthcare, Los Angeles, California, USA.
Background:
Stack-of-radial multiecho gradient-echo MRI is promising for free-breathing liver quantification and may benefit children.
Purpose:
To validate stack-of-radial MRI with self-gating motion compensation in phantoms, and to evaluate it in children.
Study Type:
Prospective.
Phantoms:
Four vials with different driven by a motion stage.
Subjects:
Sixteen pediatric patients with suspected nonalcoholic fatty liver disease or steatohepatitis (five females, 13 ± 4 years, body mass index 29.2 ± 8.6 kg/m2 ).
Field Strength/Sequences:
Stack-of-radial, and 2D and 3D Cartesian multiecho gradient-echo sequences at 3T.
Assessment:
Ungated and gated stack-of-radial proton density fat fraction (PDFF) and maps were reconstructed without and with self-gating motion compensation. Stack-of-radial measurements of phantoms without and with motion were validated against reference 2D Cartesian results of phantoms without motion. In subjects, free-breathing stack-of-radial and reference breath-hold 3D Cartesian were acquired. Subject inclusion for statistical analysis and region of interest placement were determined independently by two observers.
Statistical Tests:
Phantom results were fitted with a weighted linear model. Demographic differences between excluded and included subjects were tested by multivariate analysis of variance. PDFF and measurements were compared using Bland-Altman analysis. Interobserver agreement was assessed by the intraclass correlation coefficient (ICC).
Results:
Ungated stack-of-radial inside moving phantom vials showed a significant positive bias of 64.3 s-1 (P < 0.00001), unlike gated results (P > 0.31). Subject inclusion decisions for statistical analysis from two observers were consistent. No significant differences were found between four excluded and 12 included subjects (P = 0.14). Compared to breath-hold Cartesian, ungated and gated free-breathing stack-of-radial exhibited mean differences of 18.5 s-1 and 3.6 s-1 . Mean PDFF differences were 1.1% and 1.0% for ungated and gated measurements, respectively. Interobserver agreement was excellent (ICC for PDFF = 0.99, ICC for = 0.90; P < 0.0003).
Data Conclusion:
Stack-of-radial MRI with self-gating motion compensation seems to allow free-breathing liver and PDFF quantification in children.
Level Of Evidence:
2 TECHNICAL EFFICACY STAGE: 2.
