title: Hepatic transit time in benign liver lesions.
abstract: OBJECTIVE
  Shortening of the hepatic transit time (HTT) of an echo enhancer indicates a potential metastatic spread to the liver. Previous studies showed a significant difference in the HTT between patients with metastases (6.5 sec) and patients without liver lesions (15 sec). The influence of benign liver lesions on the HTT is unclear, although benign liver tumors are a frequent finding. We therefore compared the HTT of benign liver lesions to the HTT of liver metastases.
  
  
  METHODS
  Patients with focal liver lesions were enrolled in this study. We measured the HTT of an echo enhancer (Sonovue) in pulse inversion mode on the basis of time intensity curves (TIC). For this the hepatic artery and a branch of the hepatic vein were visualized simultaneously in an intercostal section. The difference between the arrival time of the echo enhancer in the hepatic artery and the hepatic vein offered the real HTT.
  
  
  RESULTS
  42 patients were enrolled in this study. 19 patients had metastatic growth in the liver, benign lesions were found in 23 patients. The mean HTT in patients with liver metastasis (6.4 sec +/- 1.6) was significantly less than in patients with benign lesions (10.4 sec +/- 3.4) (p < 0.001). None of the patients with liver metastasis had an HTT of greater than 10 sec.
  
  
  CONCLUSIONS
  An HTT of greater than 10 sec seems to rule out liver metastasis. If the HTT is less than 10 sec, further evaluation of the liver is needed. There are indications that benign liver lesions also lead to a shortening of the HTT, but this is less pronounced than in patients with liver metastasis.
authors.affiliation: Medicine 1, University of Erlangen Nuremberg. thomas.haendl@med1.imed.uni-erlangen.de
authors.forename: T
authors.initials: T
authors.lastname: Haendl
authors.forename: D
authors.initials: D
authors.lastname: Strobel
authors.forename: N
authors.initials: N
authors.lastname: Steinebrunner
authors.forename: M
authors.initials: M
authors.lastname: Frieser
authors.forename: E G
authors.initials: EG
authors.lastname: Hahn
authors.forename: T
authors.initials: T
authors.lastname: Bernatik
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D006391:Hemangioma / Q000000981:diagnostic imaging / Q000378:metabolism; D006499:Hepatic Artery / Q000000981:diagnostic imaging*; D006503:Hepatic Veins / Q000000981:diagnostic imaging*; D006801:Humans; D007700:Kinetics; D008099:Liver / Q000000981:diagnostic imaging* / Q000378:metabolism*; D008107:Liver Diseases / Q000000981:diagnostic imaging* / Q000378:metabolism*; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism; D008875:Middle Aged; D014463:Ultrasonography