Multimaterial decomposition algorithm for quantification of fat in hepatocellular carcinoma using rapid kilovoltage-switching dual-energy CT: A comparison with chemical-shift MR imaging

Abstract

Understanding intratumoral fat in hepatocellular carcinoma (HCC) is clinically important to elucidate prognosis. We sought to quantify HCC and liver fat with a multimaterial decomposition (MMD) algorithm with rapid kilovoltage-switching dual-energy computed tomography (DECT) relative to chemical-shift magnetic resonance imaging (CSI).In this retrospective study, 40 consecutive patients with HCC underwent non-contrast-enhanced (non-CE) and four-phases contrast-enhanced (four-CE) DECT (80 and 140 kVp) and abdominal MR imaging (including CSI) between April 2011 and December 2012. Fat volume fraction (FVFDECT) maps were generated by MMD algorithm to quantify HCC and liver fat. Fat fraction measured by CSI (FFCSI) was determined for HCC and liver on dual-echo sequence using 1.5- or 3-Tesla MR systems. The correlation between FVFDECTand FFCSIwas evaluated using Pearson correlation test, while non-CE FVFDECTand four-CE FVFDECTwere compared by one-way ANOVA and Bland-Altman analysis.Forty patients (mean age, 70.1years ± 7.8; 25 males) were evaluated. FVFDECTand FFCSIexhibited weak to moderate correlations for HCC in non-CE and four-CE except in equilibrium phase (r=0.42, 0.44, 0.35, and 0.33; all P