Three-dimensional Fast-Recovery Fast Spin-Echo MRCP: Comparison with Two-dimensional Single-Shot Fast Spin-Echo Techniques

Abstract

To retrospectively evaluate the technical quality of and the visibility of the biliary tree and pancreatic duct on magnetic resonance (MR) cholangiopancreatographic (MRCP) images obtained with a single-breath-hold three-dimensional (3D) fast-recovery fast spin-echo (FRFSE) sequence in comparison with conventional two-dimensional (2D) single-shot fast spin-echo (SSFSE) thin-section and thick-slab sequences. Institutional review board approval was obtained; informed consent was not required for this HIPAA-compliant study. MRCP was performed at 1.5 T in 53 consecutive patients (25 men and 28 women, aged 23-84 years). A single-breath-hold volume acquisition was performed by using the 3D FRFSE sequence and the conventional 2D SSFSE sequences. Two radiologists graded studies obtained with each sequence in a blinded fashion, and the paired Student t test was used to assess differences in technical quality, visibility of eight individual ductal segments of the biliary tree and pancreatic duct, and number of ductal segments visualized per patient. Studies obtained with 3D FRFSE were of significantly higher technical quality than those obtained with thin-section 2D SSFSE (P < .02 for both readers). The 3D FRFSE maximum intensity projection reconstruction and 2D SSFSE thick-slab sequence proved statistically equivalent with regard to the overall visibility of the biliary tree and pancreatic duct and the number of ductal segments visualized per patient. In comparison with 2D SSFSE thin-section imaging, however, 3D FRFSE imaging produced an improved overall duct segment visibility grade of 0.45 on a three-point visibility scale (P < .001), with a corresponding average per-patient improvement of 1.9 out of eight possible fully visualized duct segments (P < .001). The 3D FRFSE sequence shows promise for improved visibility of the pancreatic duct and biliary tree, compared with the conventional 2D SSFSE thin-section and thick-slab approach, while permitting the entire MRCP examination to be performed in a single breath hold.