Hepatic lesions: morphologic and functional characterization with multiphase breath-hold 3D gadolinium-enhanced MR angiography--initial results.

Abstract

To investigate multiphase (arterial, portal venous, and late venous phases) breath-hold three-dimensional (3D) gadolinium-enhanced magnetic resonance (MR) angiography for the detection and functional characterization of hepatic lesions. Breath-hold fast spoiled gradient-echo 3D gadolinium-enhanced MR angiography was performed in 18 patients with 35 hepatic lesions. Measurements of signal intensity were obtained for 27 seconds in each phase, with 23-second delays between the three phases. Lesion-liver visibilities at each phase on the MR angiographic, precontrast T1-weighted, T2-weighted, and postcontrast T1-weighted images were compared. The MR angiographic functional lesion characterization was based on the combined assessment of spatial variations and the evolution of contrast material enhancement in all three phases. All 35 lesions were correctly characterized on the MR angiographic images, which is significantly (P < .01) better than the precontrast T1-weighted (n = 14 [40%]), T2-weighted (n = 23 [66%]), and postcontrast T1-weighted (n = 25 [71%]) imaging results. Analysis of the spatial variations and the evolution of contrast material enhancement significantly (P < .01) improved lesion characterization in 66% (23 of 35) of all lesions. Multiphase breath-hold 3D gadolinium-enhanced MR angiography is feasible and robust and significantly improves the morphologic detection of benign or malignant lesions during the early arterial phase. It further improves the functional characterization of hepatic lesions, combining an arterial, portal-venous, and late MR angiographic phase of contrast enhancement.