HEPATIC HEMODYNAMIC-ALTERATIONS AFTER ADMINISTRATION OF ORAL CT CONTRAST AGENTS

PURPOSE: To assess the effects of oral computed tomography (CT) contra st agents on hepatic hemodynamics with duplex Doppler ultrasound (US). MATERIALS AND METHODS: Thirty healthy subjects who fasted underwent d uplex Doppler US of the hepatic artery and portal vein both before and after administration of oral CT contrast agents. Resistive indexes we re determined for the hepatic arteries. Peak and mean velocity (centim eters per second) and mean diameter were calculated for the main porta l vein. RESULTS: Statistically significant elevation of the resistive index (P < .01) of the hepatic arteries was observed after ingestion o f oral CT contrast agents. Increase in the mean resistive index at 15 minutes was 12% in the proper hepatic arteries and 20% in the intrahep atic arteries. There was a postprandial increase in mean portal venous flow compared with baseline levels (1,110 mL/min +/- 210 vs 940 mL/mi n +/- 140) (P < .05). CONCLUSION: An elevation of hepatic artery resis tance that is probably due to arterial vasoconstriction after ingestio n of oral CT contrast agents can be observed with Doppler US. Hemodyna mic changes in liver vasculature after ingestion of oral CT contrast a gents may have as yet unknown implications for CT scanning of the live r.