Improved detection of hypervascular liver lesions with CAIPIRINHA-Dixon-TWIST-volume-interpolated breath-hold examination.
OBJECTIVES
The aim of this study was to assess the diagnostic performance of a dynamic, multiphasic contrast-enhanced volume-interpolated sequence with advanced parallel imaging techniques, Dixon fat saturation, and view sharing with 5 hepatic arterial subphases for the detection of focal liver lesions.


MATERIALS AND METHODS
Twenty-four consecutive patients (13 females, 11 males; mean [SD] age, 58 [15] years) with focal liver lesions were included in this prospective study. The examination was performed at a 3-T magnetic resonance imaging system (MAGNETOM Skyra; Siemens Healthcare, Erlangen, Germany). Five dynamic arterial subphases with a temporal resolution of 2.6 seconds, starting 17 seconds after injection of the hepatobiliary contrast agent gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Eovist; Bayer HealthCare, Leverkusen, Germany), were acquired using an accelerated parallel imaging volume-interpolated sequence with view sharing (multiarterial controlled aliasing in parallel imaging results in higher acceleration-Dixon-time-resolved angiography with interleaved stochastic trajectories-volumetric interpolated breath-hold examination [MA-CDT-VIBE]). The fourth of the 5 arterial acquisition phases (ie, at 24.8 seconds after the start of contrast agent injection) was considered the equivalent of a standard hepatic arterial phase (equivalent standard arterial phase [ESAP]). The diagnostic value of all 5 dynamic arterial phases for the detection of focal liver lesions, as compared with the single ESAP, was judged in 2 independent consensus readings. The 2 consensus reading groups were blinded to each others' results. The complete, comprehensive multisequence magnetic resonance imaging examination, including T1-weighted, T2-weighted, and multiphasic contrast-enhanced sequences, served as the standard of reference for lesion detection.


RESULTS
Forty-six percent of the patients (11/24) had hypervascular lesions. In 79 % of all patients (19/24), the best arterial parenchymal contrast of one of the MA-CDT-VIBE acquisition phases was considered better than that of the ESAP. In one third of all cases (8/24 for the first and 6/24 for the second consensus reading), MA-CDT-VIBE showed an improved lesion detection rate compared with ESAP, especially in hypervascular lesions (4/11, representing 36% of all patients with hypervascular lesions). There was a high degree of interrater agreement between the 2 consensus reading groups (the Cohen κ, 0.71-1.00; P < 0.001).


CONCLUSIONS
Compared with a standard hepatic arterial phase, MA-CDT-VIBE with 5 hepatic arterial subphases demonstrated greater diagnostic accuracy for the detection of hypervascular focal liver lesions and provided a robust and optimized hepatic arterial acquisition phase.