Liver transplant rejection: value of the resistive index in Doppler US of hepatic arteries.

Abstract
The authors prospectively evaluated the accuracy of the resistive index (RI) in Doppler ultrasound (US) for the detection of the increased vascular resistance that theoretically occurs with acute liver transplant rejection. RIs were calculated for the proximal hepatic artery and a more distal hepatic artery branch in 67 liver transplant recipients. Biopsies were performed within 24 hours of transplantation, with no intervening therapy. Examination of biopsy specimens by a single pathologist revealed findings of no, minimal, or moderate to severe rejection. RIs in hepatic arteries showed no significant differences among the three pathologic groups. No correlation was found between the RI and improved or worsened rejection in 11 patients who underwent biopsy and US more than once. RIs in hepatic arteries are of no value in the prediction of liver transplant rejection.