Biliary anatomy on 3D MRCP: Comparison of volume‐rendering and maximum‐intensity‐projection algorithms

Abstract

Purpose: To compare volume-rendering (VR) and maximum-intensity-projection (MIP) of three-dimensional T2-weighted turbo spin-echo magnetic resonance cholangiopancreatography using a free-breathing navigatortriggered prospective acquisition correction (3D-TSE-PACE-MRCP) to define biliary anatomies. Materials and Methods:VR and MIP images of 3D-TSE-PACE-MRCP for 102 patients were retrospectively evaluated. Interpretation of cystic duct variation and biliary branching patterns of each image were recorded independently by two radiologists in a blinded fashion. Interpretation confidence on a five-point scale was compared using the Wilcoxon signed-rank test. The McNemar test was used to compare the accuracies of each reformation with the reference standard obtained by consensus interpretation of both the images and source images. Results:The reference standard identified all biliary bifurcations and 95 of 102 cystic duct confluences (93.1%). VR findings agreed with the reference standard findings more often than MIP with regard to cystic duct variation (94 [92.2%] vs. 76 [74.5%], P Ͻ 0.01) while there was no significant difference for biliary branching patterns (99 [97.1%] vs. 92 [90.2%], P ϭ 0.092). The mean confidence score was significantly higher with VR than MIP with regard to both cystic duct variation and biliary branching patterns (3.7 vs. 2.4; P Ͻ 0.01; 4.1 vs. 3.3; P Ͻ 0.01).Conclusion: VR reformation of 3D-TSE-PACE-MRCP defines biliary anatomies more accurately than MIP.

3D-MRCP for evaluation of intra- and extrahepatic bile ducts: comparison of different acquisition and reconstruction planes

“…Single-shot and standard MIP reconstructions of 3D MRCP were comparable in terms of anatomical bile duct visualization, whereas selective MIP postprocessing proved useful for detection of pathological alterations. In a retrospective study, Morita and colleagues compared volume rendering (VR) and MIP of 3D TSE MRCP sequences to define biliary anatomy mostly in patients without major biliary tract anomaly [18]. Definition of biliary anatomy was found to be more accurate using VR reformation than MIP.…”

“…One disadvantage of VR reconstructions is that the detection degree of each structure depends on the setting of display parameters, particularly on the lower threshold of the opacity curve. Therefore VR images need to be evaluated interactively [18]. …”

CT and MR cholangiography: advantages and pitfalls in perioperative evaluation of biliary tree

“…Among the available MRI techniques, the two most commonly used sequences are based on the T 2 weighted turbo spin-echo sequence [42]: the two-dimensional single-shot fast spin echo (2D SSFSE) sequence; and the respiratory-triggered 3D Fourier transformation fastrecovery fast-spin echo (3D FRFSE) sequence. With 2D SSFSE, the advantage of a shorter acquisition time is balanced against the inability to depict fine details of the biliary tree.…”

Magnetic resonance cholangiopancreatography in 3 Tesla: 2D MRCP versus 3D MRCP in diagnostic evaluation with special reference to different acquisition and reconstruction planes

“…Single-shot and standard MIP reconstructions of 3D MRCP were comparable in terms of anatomical bile duct visualization, whereas selective MIP post-processing proved useful for detection of pathological alterations. In a retrospective study, Morita and colleagues [18] compared volume rendering (VR) and MIP of 3D-TSE MRCP sequences to define biliary anatomy mostly in patients without major biliary tract anomaly. Definition of biliary anatomy was found to be more accurate using VR reformation than MIP.…”