Journal of magnetic resonance imaging : JMRI
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J Magn Reson Imaging · Feb 1999
Pyogenic hepatic abscesses: MRI findings on T1- and T2-weighted and serial gadolinium-enhanced gradient-echo images.
The purpose of this study was to determine the magnetic resonance imaging (MRI) features of pyogenic hepatic abscesses on T1-weighted, T2-weighted, and serial gadolinium (Gd)-enhanced T1-weighted spoiled gradient-echo (SGE) images including images acquired in the immediate, intermediate, and late phases of enhancement. The MRI studies of 20 patients with pyogenic liver abscesses were retrospectively reviewed. All patients were examined on 1.5 (n = 19) and 1.0 (n = 1) T MR scanners. ⋯ No perilesional signal changes and enhancement difference was observed in 15 lesions. Characteristic features of abscesses include: intense mural enhancement on early gadolinium-enhanced images, which persists with negligible change in thickness and intensity on later post-gadolinium images, and the presence of periabscess increased enhancement on immediate post-gadolinium images. These MRI features may help to distinguish abscesses from other focal liver lesions during differential diagnosis.
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J Magn Reson Imaging · Feb 1999
A retrospective analysis of the accuracy of T2-weighted images and dynamic gadolinium-enhanced sequences in the detection and characterization of focal hepatic lesions.
The aim of this study was to determine the relative ability of T2-weighted and dynamic gadolinium-enhanced T1-weighted gradient-echo sequences to detect and characterize focal hepatic lesions. We retrospectively studied 37 patients with proven focal hepatic lesions using the following sequences: a T1-weighted spin-echo sequence (T1), a T2-weighted sequence (T2), and a series of breath-hold dynamic gadolinium-enhanced T1-weighted gradient-echo sequences (Gd). Two observers were asked to determine retrospectively the number and type of focal hepatic lesions present using images from three combinations of sequences (T1+T2, T1+Gd, T1+T2+Gd). ⋯ Both readers detected more focal lesions when both the T2-weighted sequences and the gadolinium-enhanced sequences were available than on either sequence alone, although this improvement reached statistical significance (P<0.05) only for one of the readers. There was no significant difference (P<0.05) in the ability to characterize lesions between any of the sets of sequences. The combination of dynamic gadolinium-enhanced images and T2-weighted images was shown to assess focal hepatic lesions better than either of these sequences alone.