MR cholangiopancreatography: comparison of 2D single-shot fast spin-echo and 3D fast spin-echo sequences

Abstract

Purpose: To compare 2D single-shot Fast Spin-Echo (FSE) and two 3D FSE MR cholangiopancreatography (MRCP) sequences with different slice thickness in the evaluation of normal and abnormal biliary and pancreatic duct systems.

Materials and methods: Thirty-two consecutive patients, both with normal biliary and pancreatic ducts (n=14) and with different biliary and/or pancreatic duct disease (n=18) underwent MRCP with a 1.5 T superconductive magnet. One 2D single-shot FSE and two 3D FSE MRCP sequences with different slice thickness (1.6 mm and 3 mm) were performed in each patient. Images were analysed with regards to: artefacts (0=none, 1=minimal, 2=present but not affecting the diagnostic evaluation, 3=present and affecting the diagnostic evaluation), image quality (0=non-diagnostic, 1=poor, 2=fair, 3=good, 4=excellent), duct conspicuity (0=not-visible, 1=poor, 2=good, 3=excellent), diagnostic confidence (possible presence of dilatations, stones and stenoses).

Results: Artefacts were rarely present, without significant differences among the three sequences. The 2D single-shot FSE sequence provided a significantly better image quality and significantly better conspicuity of the intrahepatic and pancreatic ducts in comparison to both the 1.6-mm and 3-mm thickness 3D FSE sequences. The three sequences yielded identical results in the detection of 17 cases of dilatation and 10 cases of stenosis as well as in the evaluation of their degree. Stones in the biliary tree were detected in 6 cases with the 2D single-shot FSE sequence, in 5 cases in the MIP images of the 3D FSE sequence with slice thickness of 1.6 mm and in 4 cases in the MIP images of the 3D FSE sequence with slice thickness of 3 mm. The diagnostic confidence did not show statistically significant differences among the three sequences.

Conclusions: The 2D single-shot FSE sequence proved to be superior to the 3D FSE sequences in the evaluation of normal and abnormal biliary and pancreatic duct systems.