A COMPARISON OF MR AND DUPLEX-DOPPLER ULTRASOUND FOR VASCULAR ASSESSMENT PRIOR TO ORTHOTOPIC LIVER-TRANSPLANTATION

A prospective blinded comparison of duplex Doppler ultrasound (DDU) an d a magnetic resonance angiography (MRA) 2-D time-of-flight technique was performed to assess the hepatic vasculature in 23 adult patients r eferred for orthotopic liver transplantation. Both techniques confirme d patency of the inferior vena cava in all patients, demonstrated a co mplete portal vein occlusion in one patient, and accurately defined th e vascular and organ anatomy in a patient with situs inversus. The res ults were confirmed at surgery in 18 of the patients who have subseque ntly undergone liver transplantation. In one patient a partial portal vein thrombosis was found at surgery which was not detected by either imaging technique. MRA was more sensitive overall in detecting porto-s ystemic collaterals (31 locations in 17 patients) compared with ultras ound (24 locations in 17 patients), although ultrasound detected more patients with recanalized para-umbilical veins (DDU: 10 patients; MRA: 8 patients). These results indicate that a simple MRA technique can e qual duplex Doppler ultrasound for the non-invasive assessment of pate ncy of the hepatic vasculature and should be considered when DDU exami nation is equivocal or technically inadequate. MRA may provide additio nal information on the presence and size of porto-systemic collaterals which may be of value in monitoring portal hypertension.