Ultraschall Med 2005; 26 - OP050
DOI: 10.1055/s-2005-917331

HEPATIC TRANSIT TIME ALLOWS DIFFERING BETWEEN BENIGN AND MALIGNANT LIVER LESIONS

T Haendl 1, D Strobel 1, N Steinerbrunner 1, M Frieser 1, EG Hahn 1, T Bernatik 1
  • 1Department of Medicine I, University of Erlangen-Nuremberg, Erlangen, Germany

Purpose: Shortening of the hepatic transit time (HTT) of an echo enhancer (hepatic artery to hepatic vein delay) indicates metastatic spread to the liver. Previous studies showed an average transit time of about 15s in patients without liver lesions, and about 6.5s in patients with known liver metastasis.

Is there an influence of benign liver lesions on the hepatic transit time? Permits the change of the hepatic transit time discrimination between malignant and benign lesions?

Methods and Materials: Patients with sonographically found liver lesions were enrolled in this study. The dignities of the liver lesions were proven either by MRI or biopsy.

We measured the HTT of an echo enhancer (Sonovue®) in pulse inversion mode on the basis of time intensity curves (TIC) in patients with focal liver lesions. The hepatic artery and a hepatic vein were visualized simultaneously in an intercostal section. The difference of the arrival time of the echo enhancer in the hepatic vein and the hepatic artery supplied the real HTT.

Results: Of 44 patients enrolled in this study 2 (5%) had primary liver tumors (HCC) based on cirrhosis. These were excluded of further statistical analysis due to the complex hemodynamic changes in liver cirrhosis. 19 (43%) patients had metastatic growth in the liver. Benign lesions were found in 23 (52%) patients. The mean HTT in patients with liver metastasis was 6.4s±1.6, whereas in patients with benign lesions it was significantly longer 10.4s±3.4 (p<0.001). None of the patients with liver metastasis had an HTT of more than 10s. HTT of more than 10s excludes a metastatic spread to the liver (sensitivity 100%), whereas about half of the patients with benign lesions had an HTT of less than 10s (specificity of 52%). Neither size nor amount of benign liver lesions seems to have an impact on the HTT. At the same time there was no influence of age or cardiovascular drugs on the HTT.

Conclusions: Measurement of HTT (HTT>10s) allows ruling out liver metastasis.

In case of HTT shortening further evaluation of the liver is needed.

Benign liver lesions do also lead to a shortening of HTT, even though this is significantly less pronounced than the HTT shortening in patients with liver metastasis.