Retrospective Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. Oct 28, 2023; 15(10): 293-303
Published online Oct 28, 2023. doi: 10.4329/wjr.v15.i10.293
Two-point Dixon and six-point Dixon magnetic resonance techniques in the detection, quantification and grading of hepatic steatosis
Mohamed Elfaal, Alanna Supersad, Craig Ferguson, Stephanie Locas, Florin Manolea, Mitchell P Wilson, Medica Sam, Wendy Tu, Gavin Low
Mohamed Elfaal, Alanna Supersad, Craig Ferguson, Stephanie Locas, Florin Manolea, Mitchell P Wilson, Medica Sam, Wendy Tu, Gavin Low, Department of Radiology & Diagnostic Imaging, University of Alberta, Edmonton T6G2B7, Alberta, Canada
Author contributions: Elfaal M, Supersad A, Ferguson C, Locas S, Manolea F, Wilson MP, Sam M, Tu W, and Low G contributed to data collection, data analysis, editing the manuscript; and all authors approved the final manuscript.
Institutional review board statement: The study was reviewed and approved by the Ethics Committee of the University of Alberta, Canada and the Institutional Review Board of Alberta Health Services and Northern Alberta Clinical Trials and Research Centre.
Informed consent statement: The Ethics Committee of the University of Alberta, Canada, waived the requirement for signed informed consent for this retrospective study for which anonymous clinical data was used.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Data sharing statement: No additional data is available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Gavin Low, MBChB, MPhil, MRCS, FRCR, Professor, Department of Radiology & Diagnostic Imaging, University of Alberta, WMC 2B2.41 8440-112 ST, Edmonton T6G2B7, Alberta, Canada. gavinlow@mic.ca
Received: September 6, 2023
Peer-review started: September 6, 2023
First decision: September 19, 2023
Revised: September 20, 2023
Accepted: September 28, 2023
Article in press: September 28, 2023
Published online: October 28, 2023
Processing time: 47 Days and 18.3 Hours
Abstract
BACKGROUND

Hepatic steatosis is a very common problem worldwide.

AIM

To assess the performance of two- and six-point Dixon magnetic resonance (MR) techniques in the detection, quantification and grading of hepatic steatosis.

METHODS

A single-center retrospective study was performed in 62 patients with suspected parenchymal liver disease. MR sequences included two-point Dixon, six-point Dixon, MR spectroscopy (MRS) and MR elastography. Fat fraction (FF) estimates on the Dixon techniques were compared to the MRS-proton density FF (PDFF). Statistical tests used included Pearson’s correlation and receiver operating characteristic.

RESULTS

FF estimates on the Dixon techniques showed excellent correlation (≥ 0.95) with MRS-PDFF, and excellent accuracy [area under the receiver operating characteristic (AUROC) ≥ 0.95] in: (1) Detecting steatosis; and (2) Grading severe steatosis, (P < 0.001). In iron overload, two-point Dixon was not evaluable due to confounding T2* effects. FF estimates on six-point Dixon vs MRS-PDFF showed a moderate correlation (0.82) in iron overload vs an excellent correlation (0.97) without iron overload, (P < 0.03). The accuracy of six-point Dixon in grading mild steatosis improved (AUROC: 0.59 to 0.99) when iron overload cases were excluded. The excellent correlation (> 0.9) between the Dixon techniques vs MRS-PDFF did not change in the presence of liver fibrosis (P < 0.01).

CONCLUSION

Dixon techniques performed satisfactorily for the evaluation of hepatic steatosis but with exceptions.

Keywords: Chemical shift encoded Dixon magnetic resonance techniques; Hepatic steatosis; Liver fat quantification; Magnetic resonance spectroscopy; Proton density fat fraction; Ultrasound

Core Tip: Fat fraction (FF) estimates on the Dixon techniques (two-point Dixon and six-point Dixon) have excellent correlation with magnetic resonance spectroscopy-proton density FF (MRS-PDFF), and excellent accuracy in detecting steatosis, and grading severe steatosis. However, in iron overload, two-point Dixon was not evaluable due to confounding effect on liver signal from T2* decay. The excellent correlation between the Dixon techniques vs MRS-PDFF was not affected by co-existing liver fibrosis.