Assessment of vascular and biliary complications after liver transplantation: imaging with multidetector computed tomography angiography (MDCT-A), doppler us and contrast-enhanced us (CEUS)
Objectives: Early complications after liver transplantation usually occur in the vascular compartment (thrombosis, pseudoaneurysm, vasospasm of the hepatic arteries, portal hypertension, portal stenosis, hepatic veins stenosis or congestion) and in the intrahepatic biliary system. The early detection of blood flow through the liver after transplantation affects prognosis. The purpose of this study was to evaluate the efficacy of Doppler US, CEUS and MDCT-A for the diagnosis of complications in the hepatic vessels and bile ducts.
Methods: In the early postoperative follow-up of liver transplant recipients, 20 patients underwent colour Doppler sonograms before and after intravenous injection of the ultrasound contrast agent SonoVue. The hepatic artery, portal vein, hepatic veins and bile ducts were evaluated in the hepatic portal and in the left and right lobe. All the findings were correlated with MDCT-A results or surgery considered as reference standard.
Results: Visualization of the portal vein and hepatic veins was similar without and with contrast medium. Hepatic arteries were visualized in 16 patients without contrast medium, in 19 patients with contrast medium. The remaining patient showed hepatic artery thrombosis, which was confirmed MDCT-angiographically. US also detected biliary complications in 7 patients (segmental ducts excluded from the anastomosis, stenosis of the biliodigestive anastomosis, lithiasis) and normal bile ducts in the remaining 13 cases.
Conclusions: US enables early detection of hepatic vessels and intrahepatic biliary tree complications. Imaging of hepatic arteries and peripheral portal vein branches after liver transplantation improves significantly with the use of contrast-enhanced sonography.