@article{daebaa6000c64e6ca09225478245cb8a,
title = "Multisite multivendor validation of a quantitative MRI and CT compatible fat phantom",
abstract = "Purpose: Chemical shift-encoded magnetic resonance imaging enables accurate quantification of liver fat content though estimation of proton density fat-fraction (PDFF). Computed tomography (CT) is capable of quantifying fat, based on decreased attenuation with increased fat concentration. Current quantitative fat phantoms do not accurately mimic the CT number of human liver. The purpose of this work was to develop and validate an optimized phantom that simultaneously mimics the MRI and CT signals of fatty liver. Methods: An agar-based phantom containing 12 vials doped with iodinated contrast, and with a granular range of fat fractions was designed and constructed within a novel CT and MR compatible spherical housing design. A four-site, three-vendor validation study was performed. MRI (1.5T and 3T) and CT images were obtained using each vendor's PDFF and CT reconstruction, respectively. An ROI centered in each vial was placed to measure MRI-PDFF (%) and CT number (HU). Mixed-effects model, linear regression, and Bland-Altman analysis were used for statistical analysis. Results: MRI-PDFF agreed closely with nominal PDFF values across both field strengths and all MRI vendors. A linear relationship (slope = −0.54 ± 0.01%/HU, intercept = 37.15 ± 0.03%) with an R2 of 0.999 was observed between MRI-PDFF and CT number, replicating established in vivo signal behavior. Excellent test-retest repeatability across vendors (MRI: mean = −0.04%, 95% limits of agreement = [−0.24%, 0.16%]; CT: mean = 0.16 HU, 95% limits of agreement = [−0.15HU, 0.47HU]) and good reproducibility using GE scanners (MRI: mean = −0.21%, 95% limits of agreement = [−1.47%, 1.06%]; CT: mean = −0.18HU, 95% limits of agreement = [−1.96HU, 1.6HU]) were demonstrated. Conclusions: The proposed fat phantom successfully mimicked quantitative liver signal for both MRI and CT. The proposed fat phantom in this study may facilitate broader application and harmonization of liver fat quantification techniques using MRI and CT across institutions, vendors and imaging platforms.",
keywords = "computed tomography, fat, liver, magnetic resonance imaging, phantom",
author = "Ruiyang Zhao and Diego Hernando and Harris, {David T.} and Hinshaw, {Louis A.} and Ke Li and Lakshmi Ananthakrishnan and Bashir, {Mustafa R.} and Xinhui Duan and Ghasabeh, {Mounes Aliyari} and Kamel, {Ihab R.} and Carolyn Lowry and Mahadevappa Mahesh and Daniele Marin and Jessica Miller and Pickhardt, {Perry J.} and Jean Shaffer and Takeshi Yokoo and Brittain, {Jean H.} and Reeder, {Scott B.}",
note = "Funding Information: The authors acknowledge support from the Wisconsin State Economic Engagement and Development (SEED) Program, as well as the NIH (R01 DK088925, R01 DK100651, R41 EB025729, R44 EB025729, K24 DK102595, and R01 DK083380). Further, the authors wish to thank GE Healthcare, who provides research support to the University of Wisconsin and Duke University, Siemens Healthineers who provides research support to the University of Wisconsin-Madison, the Johns Hopkins University, Duke University, and the University of Texas-Southwestern, Philips Healthcare who provides research support to the University of Texas-Southwestern. Finally, Dr. Reeder is a Romnes Faculty Fellow, and has received an award provided by the University of Wisconsin-Madison Office of the Vice Chancellor for Research and Graduate Education with funding from the Wisconsin Alumni Research Foundation. The authors wish to thank David Rutkowski from Calimetrix for helpful discussions. Funding Information: The authors acknowledge support from the Wisconsin State Economic Engagement and Development (SEED) Program, as well as the NIH (R01 DK088925, R01 DK100651, R41 EB025729, R44 EB025729, K24 DK102595, and R01 DK083380). Further, the authors wish to thank GE Healthcare, who provides research support to the University of Wisconsin and Duke University, Siemens Healthineers who provides research support to the University of Wisconsin‐Madison, the Johns Hopkins University, Duke University, and the University of Texas‐Southwestern, Philips Healthcare who provides research support to the University of Texas‐Southwestern. Finally, Dr. Reeder is a Romnes Faculty Fellow, and has received an award provided by the University of Wisconsin‐Madison Office of the Vice Chancellor for Research and Graduate Education with funding from the Wisconsin Alumni Research Foundation. The authors wish to thank David Rutkowski from Calimetrix for helpful discussions. Publisher Copyright: {\textcopyright} 2021 American Association of Physicists in Medicine",
year = "2021",
month = aug,
doi = "10.1002/mp.15038",
language = "English (US)",
volume = "48",
pages = "4375--4386",
journal = "Medical Physics",
issn = "0094-2405",
publisher = "AAPM - American Association of Physicists in Medicine",
number = "8",
}