Contrast-enhanced ultrasound in the evaluation of hepatic artrey complication with collateral transformation after liver transplantation

Objective To summarize the contrast-enhanced ultrasonographic(CEUS) features of hepatic artery complication with collateral transformation after liver transplantation and to explore the diagnostic value of CEUS for collateral transformation of hepatic artery.Methods All 30 post-orthotopic liver transplantation patients suspected hepatic artery complication by color Doppler flow imaging or clinical manifestation were performed CEUS,digital subtraction angiography(DSA) and/or computed tomography combining computed tomography angiography(CT+CTA) at liver transplantation center of the Third Affiliated Hospital of Sun Yat-sen University between April 2004 and December 2011.Hepatic artery CEUS features of patients with collateral transformation of hepatic artery and patients without collateral transformation of hepatic artery were retrospectively compared.Results There were 30 post-orthotopic liver transplantation patients,including 11 patients with collateral transformation of hepatic artery confirmed by CT+CTA or DSA and 19 patients without collateral transformation of hepatic artery confirmed by DSA.The diagnostic time of hepatic artery complication in patients with collateral transformation of hepatic artery was significantly later than that of patients without collateral transformation of hepatic artery(144-1917 d,median 304 d vs 5-232 d,median 47 d,U=20,P0.01).All 11 patients with collateral transformation of hepatic artery had hepatic artery complication and most of them were hepatic artery thrombosis(HAT) patients(9/11,81.8%);however,most of patients without collateral transformation of hepatic artery were hepatic artery stenosis(HAS) patients(15/19,78.9%) and one of them had normal hepatic artery.The distribution of hepatic artery complication types between two groups was significantly different(Fisher′s exact test,P=0.001).Patients with collateral transformation of hepatic artery hadn not evident clinical symptoms,but most of them showed bile duct abnormality(10/11) in conventional ultrosonography.Hepatic artery CEUS features of patients with collateral transformation of hepatic artery had particular features as follows:(1)Proper hepatic artery in most patients could not be displayed(10/11).(2)Small,tortuous arteries gathered as reticulate(5/11) or patchy(6/11) pattern,accompanied with stripe enhanced pattern(2/11) in porta hepatis.The proper hepatic arteries were displayed and no other arteries at porta hepatic were displayed in all patients without collateral transformation of hepatic artery except 3 HAT patients.Conclusion Collateral transformation of hepatic artery in patients with hepatic artery complication after liver transplantation had some particular features in CEUS which may be a new method to diagnose collateral transformation of hepatic artery.