Ischemic-type biliary lesions in liver transplant recipients: evaluation with magnetic resonance cholangiography

We assessed the diagnostic value of magnetic resonance cholangiography (MRC) when evaluating ischemic-type biliary lesions in the follow-up of liver transplant patients. We retrospectively reviewed magnetic resonance imaging and MRC of 28 liver transplant recipients with ischemic changes of the biliary tree. The MR examinations were performed at 1.5 T. After the acquisition of axial T1w and T2w sequences, MRC involved a coronal respiratory-triggered, fat-suppressed, two-dimensional, thin-slab, heavily T2w fast spin-echo sequence, and/or a coronal breath-hold, thin- and thick-slab, single-shot T2w sequence. Eleven patients underwent either surgical reconstruction of the biliary system (n = 4) or liver retransplantation (n = 7); the pathologic specimens were employed as standard of reference. The final diagnosis was obtained through direct cholangiography in the remaining cases. Without knowledge of the surgical, pathologic, and cholangiographic findings, two experienced investigators evaluated in conference the MR images to determine the presence of biliary tract abnormalities. MRC demonstrated strictures involving the hepatic bifurcation and the extrahepatic bile duct of the graft in 26 patients; a concomitant thickening of the biliary wall was described in 18 out of these 26 subjects. MRC also showed sludge or stones formation in the donor common bile duct in 16 out of these patients. In conclusion, MRC allows noninvasive, reliable, assessment of ischemic-type biliary lesions in liver transplant recipients.