Duplex Doppler ultrasonography for monitoring liver transplants.

The utility of duplex Doppler ultrasonography (US) for monitoring was evaluated after 19 liver transplantations. The assessment of the resistive index (RI) of the hepatic arteries showed no significant difference in the RI measured in grafts with stable function compared with grafts with ischemic damage, acute rejection, chronic rejection, or cytomegalovirus hepatitis. Nor was there any correlation between the levels of RI and the severity of acute rejection. In 2 out of 5 liver transplants in which hepatic artery pulsations were not identified with US, hepatic artery thrombosis was found at angiography. Although high echogenicity of the parenchyma was often observed during acute rejection episodes, it was not diagnostic for rejection. Fluid collections observed around the grafts resolved spontaneously. Thus, duplex Doppler US for monitoring liver transplants is especially useful for the diagnosis of hepatic artery thrombosis. It was not helpful for the diagnosis of acute or chronic rejection.