The objective of this study was to evaluate the feasibility and accuracy of postcontrast, dual-energy computed tomography (DECT) using multimaterial decomposition (MMD) for quantification of the hepatic fat fraction (HFF).
Various degrees of fatty liver were produced in 16 rabbits divided into 4 groups, by feeding them a high-fat, high-cholesterol diet. After 6 weeks, precontrast, single-energy computed tomography (SECT) and postcontrast DECT were performed, and HFF maps were obtained from the DECT using MMD. T2*-corrected, multiecho, chemical-shift imaging for obtaining the proton density fat fraction (PDFF) map and histologic assessment of the hepatic steatosis were also performed. The Pearson correlations coefficients were calculated, and Bland-Altman analysis was performed of the fat fractions determined by DECT, magnetic resonance imaging (MRI), and pathology. Receiver operating characteristic curve analysis was performed to detect 5% hepatic steatosis or greater. The histologic HFF was used as the reference standard, and PDFFs determined by chemical-shift imaging as the technical standard.
The HFFs calculated by MMD of postcontrast DECT scans were strongly correlated with those of pathology as well as the PDFFs of MRI (P < 0.05), and the mean differences of the Bland-Altman plots between the HFFs of DECT with MMD and the PDFFs of MRI were close to zero. The diagnostic performance of postcontrast DECT with MMD for detecting 5% hepatic steatosis or greater was comparable to that of the attenuation value of precontrast SECT and the PDFFs of MRI (P = 0.17–0.82).
Quantification of the HFF using postcontrast DECT with MMD was feasible and showed comparable sensitivity and specificity to the precontrast SECT for the detection of hepatic steatosis.
From the *Department of Radiology, SMG-SNU Boramae Medical Center; and †Department of Radiology, ‡Institute of Radiation Medicine, and §Department of Pathology, Seoul National University Hospital, Seoul, Korea.
Received for publication April 24, 2014; accepted July 17, 2014.
Reprints: Jeong Min Lee, MD, PhD, Department of Radiology, Seoul National University Hospital, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea (e-mail: firstname.lastname@example.org).
This study was supported by GE Healthcare CT research.
J.M.L. is currently receiving a grant from Bayer Healthcare, Guerbe, and GE Healthcare and was on the speaker’s bureau for Bayer Healthcare. B.I.C. previously received a grant from Dongseo Medical, CMS, and Acuzen Company. For the remaining authors, no conflicts of interest or funding sources were declared.