Hepatic arterial blood flow velocities: assessment by transcutaneous and intravascular Doppler sonography.

Background/aims: Doppler sonography has been used to assess hepatic arterial perfusion in a number of published reports. However, adequate validation studies are available for neither the transcutaneous nor the intravascular Doppler approach. The aim of this comparative study was to assess hepatic arterial perfusion with both methods.

Methods: In 15 patients the right hepatic artery was examined with intravascular and transcutaneous Doppler sonography after calibration of Doppler devices in vitro with a thread model. The measurements were performed simultaneously in five and separately within 24 h in 10 patients.

Results: In vitro, the correlations between the velocities of the thread and the velocities as determined by intravascular (r=1.0, p<0.001) and transcutaneous Doppler sonography (r=1.0, p<0.001) were excellent. In vivo, the best correlation was found for systolic peak velocities (intravascular: 58.5+/-18.1 cm/s, mean+/-standard deviation, transcutaneous: 58.2+/-25.2 cm/s, r=0.63, p=0.01). Although lower mean (intravascular: 26.5+/-7.7 cm/s, transcutaneous: 32.5+/-14.4 cm/s) and end-diastolic velocities (intravascular: 11.5+/-4.0 cm/s, transcutaneous: 18.4+/-8.6 cm/s) were found with intravascular compared to transcutaneous Doppler sonography, significant correlations were demonstrable between results obtained by both methods (r=0.63, p=0.01 for mean and r=0.57, p=0.025 for diastolic velocities). Similarly, the calculated resistive (intravascular: 0.79+/-0.07, transcutaneous: 0.68+/-0.06, r=0.65, p=0.009) and pulsatility indices (intravascular: 1.78+/-0.47, transcutaneous: 1.26+/-0.25, r=0.55, p=0.034) were somewhat higher using the intravascular device, but correlated well with the numbers obtained by the transcutaneous approach.

Conclusions: The data suggest that with use of different Doppler devices, systolic velocities are the most suitable parameter for Doppler assessment of hepatic arterial perfusion.