3D Multiecho Dixon for the Evaluation of Hepatic Iron and Fat in a Clinical Setting. Issue 3 (22nd February 2017)

• Record Type: Journal Article
• Authors: Henninger, Benjamin; Zoller, Heinz; Kannengiesser, Stephan; Zhong, Xiaodong; Jaschke, Werner; Kremser, Christian
• Is Part Of: Journal of magnetic resonance imaging. Volume 46:Issue 3(2017)
• Page Start: 793
• Page End: 800
• Publication Date: 2017-02-22
• Subjects: MRI -- liver -- iron -- fat -- Dixon -- relaxometry; Magnetic resonance imaging -- Periodicals; 616
• DOI: 10.1002/jmri.25630
• Languages: English
• ISSNs: 1053-1807

Abstract

Abstract : Purpose: To prospectively evaluate a new 3D‐multiecho‐Dixon (3D‐ME‐Dixon) sequence for the quantification of hepatic iron and fat in a clinical setting. Materials and Methods: In all, 120 patients underwent 1.5T magnetic resonance imaging of the liver between December 2013 and June 2015 including the following three sequences: 3D‐ME‐Dixon with inline calculation of R2* and proton‐density fat‐fraction (PDFF) maps, single‐voxel‐spectroscopy (SVS), 2D multigradient‐echo sequence (2D‐ME‐GRE). SVS and 2D‐ME‐GRE were used as reference for PDFF and R2*, respectively. R2*‐ and PDFF‐values from 3D‐ME‐Dixon were compared with those of the reference. Linear regression analysis, Bland–Altman plots, and agreement parameters were calculated. Results: In total, 103 patients were finally included (87 men and 16 women; mean age, 50.51 years); 17/120 were excluded due to fat/water‐swaps or R2*‐values exceeding the constraint of 400 1/s for 3D‐ME‐Dixon. A strong correlation ( r = 0.992, P < 0.001) between R2* of 3D‐ME‐Dixon and the reference 2D‐ME‐GRE was found. Bland–Altman analysis revealed systematically lower values for 3D‐ME‐Dixon (16.499%). Using an adapted threshold of 57 1/s, 3D‐ME‐Dixon obtained a positive/negative percentage agreement (PPA/NPA) of 84.4%/91.4% for detecting hepatic iron overload. For hepatic fat the correlation between 3D‐ME‐Dixon and the reference SVS was strong ( r = 0.957, P < 0.001); PPA/NPA was 88.3%/91.4%. Conclusion: The 3D‐ME‐Dixon sequence is a valuable tool for the evaluation of hepatic iron and fat in a clinical setting. Fat/water‐swaps remain a drawback requiring improvements to the implementation and making it necessary to have proven conventional sequences at hand in case of an eventual occurrence. Level of Evidence : 1. Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:793–800