Hepatic vein transit time of an ultrasound contrast agent: simplified procedure using pulse inversion imaging

Abstract

The aim of this study was to ascertain whether a new ultrasound technique, namely pulse inversion imaging, could assess the arrival of a contrast agent in the hepatic veins, and to describe possible advantages of this procedure in determining transit time over a previously described method based upon spectral Doppler quantification. 15 subjects were scanned using pulse inversion imaging. A bolus injection of 2.5 g Levovist (Schering AG, Berlin, Germany) 300 mg x ml(-1) was given into an antecubital vein. Median transit times of 16 s (range 14-20 s) were found in patients with liver cirrhosis (n=4), 22 s (range 16-27 s) in patients with focal liver lesions (n=8) and 31 s (range 30-32 s) in control subjects (n=3). The maximum interobserver variation was 2 s and the maximum intraobserver variation was 3 s (n=10). Transit time was assessed by both pulse inversion imaging and spectral Doppler quantification in six patients. Comparison of the two methods showed transit times within 2 s apart in five patients and within 5 s apart in one patient. In conclusion, it is possible to assess transit time using pulse inversion imaging. This method is simpler than a previously described method requiring computer analysis. Moreover, several liver veins can be assessed simultaneously. Different transit times were observed in different liver veins in two patients with liver tumours. A short transit time (<27 s) appears to be found only in patients with liver disease. After transit time assessment, it is possible to use the injected contrast agent for late phase imaging of the liver parenchyma.

Intrahepatic Transit Time Predicts Liver Fibrosis in Patients with Chronic Hepatitis B: Quantitative Assessment with Contrast-Enhanced Ultrasonography

“…Using spectral Doppler imaging, Albrecht et al (1999) reported that cirrhosis was associated with an appreciably shorter hepatic vein transit time compared with controls and patients with noncirrhotic diffuse liver disease. Bang et al (2001) found that pulse-inversion imaging was a simpler and more practical technique than the spectral Doppler method in evaluating hepatic transit time in a clinical setting. However, the majority of these studies used the first-generation contrast agent (Levovist, Schering AG, Berlin, Germany) and a high mechanical index technique, in which contrast microbubbles were destroyed in the scanning plane and continuous perfusion imaging was not possible.…”

Portalsystemic hemodynamic changes in chronic severe hepatitis B: An ultrasonographic study

“…In recent years, some new techniques and methods have been introduced to the hemodynamic study in liver. For example, hepatic vein transit time was measured by spectral Doppler or pulse-inversion imaging [30,31] .…”

Functional studies

“…1). This simplified technique not only simplifies measurements of the arrival time in hepatic veins but also enables measurement of the delay between arrival in the hepatic arteries and hepatic vein which was not possible with the spectral Doppler technique [6,7]. These studies used offline P111 Fig.…”