Objective: Biliary strictures after liver transplantation are common. We aimed to compare different magnetic resonance cholangiopancreatography (MRCP) sequences with regard to their diagnostic accuracy in depicting anastomotic stenoses (AST), ischaemic-type biliary lesions (ITBL) and cholelithiasis.
Methods: In patients with clinically suspected biliary obstruction after liver transplantation, MRCP was performed at 1.5 T using two-dimensional (2D) single-shot RARE, 2D T2-weighted (T2w) HASTE, 2D TrueFISP and 3D T2w TSE RESTORE sequences. The presence and localisation of lesions were assessed for each sequence independently and all sequences together. Endoscopic retrograde cholangiopancreatography (ERCP) served as the "gold standard".
Results: Biliary strictures were detected with a sensitivity of 96% by MRCP and most accurately depicted when all sequences were analysed together. AST was visualised with highest sensitivity on TrueFISP and 3D T2w TSE sequences (79%). For ITBL highest sensitivity was found with the HASTE sequence (81%). Highest sensitivity for filling defects was revealed by the 3D T2w TSE sequence (54%). Receiver operating characteristic (ROC) curve/area under the curve (AUC) analysis revealed the best results for the 3D T2w TSE sequence.
Conclusion: Our results underline the value of different MRCP sequence types for the depiction of biliary lesions. A clinical protocol consisting of different sequences may be helpful depending on the clinical question and the likely underlying abnormality.