Hepatic hemodynamic alterations after administration of oral CT contrast agents.

Abstract

To assess the effects of oral computed tomography (CT) contrast agents on hepatic hemodynamics with duplex Doppler ultrasound (US). Thirty healthy subjects who fasted underwent duplex Doppler US of the hepatic artery and portal vein both before and after administration of oral CT contrast agents. Resistive indexes were determined for the hepatic arteries. Peak and mean velocity (centimeters per second) and mean diameter were calculated for the main portal vein. Statistically significant elevation of the resistive index (P < .01) of the hepatic arteries was observed after ingestion of oral CT contrast agents. Increase in the mean resistive index at 15 minutes was 12% in the proper hepatic arteries and 20% in the intrahepatic arteries. There was a postprandial increase in mean portal venous flow compared with baseline levels (1,110 mL/min +/- 210 vs 940 mL/min +/- 140) (P < .05). An elevation of hepatic artery resistance that is probably due to arterial vasoconstriction after ingestion of oral CT contrast agents can be observed with Doppler US. Hemodynamic changes in liver vasculature after ingestion of oral CT contrast agents may have as yet unknown implications for CT scanning of the liver.