title: Early changes in liver perfusion caused by occult metastases in rats: detection with quantitative CT.
abstract: OBJECTIVE
  To determine whether computed tomography (CT) can depict liver hemodynamic changes caused by occult hepatic micrometastases in rat.
  
  
  METHODS
  Liver micrometastases (mean diameter, 500 micrometer +/- 300) were produced in seven BD IX rats by injecting 10(7) DHDK12 PROb colorectal carcinoma cells into the spleen. Macrometastases (mean diameter, 7 mm +/- 3) were produced in four other rats. Five normal rats were studied as controls. CT images were obtained every 300 msec for 30 seconds during the injection of 1 mL per kilogram of body weight of contrast medium. The time-attenuation curves of the aorta, portal vein, and liver were used to calculate liver perfusion with a deconvolution model designed for the dual blood supply.
  
  
  RESULTS
  Micrometastases in an apparently normal liver caused a 34% decrease in portal blood flow and a 25% increase in the mean transit time for the blood to pass through the liver. These findings suggest increased resistance in the sinusoidal capillaries. Similar but greater changes were found in the macrometastases.
  
  
  CONCLUSIONS
  Occult liver micrometastases in rats generate changes in liver perfusion that can be detected with CT.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale (INSERM) U494, Paris, France. ca@cuenod.net
authors.forename: C
authors.initials: C
authors.lastname: Cuenod
authors.forename: I
authors.initials: I
authors.lastname: Leconte
authors.forename: N
authors.initials: N
authors.lastname: Siauve
authors.forename: A
authors.initials: A
authors.lastname: Resten
authors.forename: C
authors.initials: C
authors.lastname: Dromain
authors.forename: B
authors.initials: B
authors.lastname: Poulet
authors.forename: F
authors.initials: F
authors.lastname: Frouin
authors.forename: O
authors.initials: O
authors.lastname: Clément
authors.forename: G
authors.initials: G
authors.lastname: Frija
mesh_terms: D000818:Animals; D003287:Contrast Media; D006499:Hepatic Artery / Q000000981:diagnostic imaging; D007472:Iohexol / Q000031:analogs & derivatives; D008102:Liver Circulation; D008114:Liver Neoplasms, Experimental / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000556:secondary*; D008297:Male; D011169:Portal Vein / Q000000981:diagnostic imaging; D051381:Rats; D011919:Rats, Inbred Strains; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; C093233:iobitridol; D007472:Iohexol