title: Detection of liver micrometastases from colorectal origin by perfusion CT in a rat model.
abstract: BACKGROUND
  Some patients with colorectal carcinoma have liver metastases (LMs) which cannot be detected by conventional imaging. This study aimed to assess whether hepatic perfusion changes induced by micrometastases can be detected by perfusion computed tomography (CT).
  
  
  METHODS
  LMs were produced in rats by injecting carcinoma cells into the portal vein. Perfusion CT was performed at microscopic (day 10), interval (day 17), and macroscopic stage (day 34). Perfusion parameters were computed using a dual-input one-compartmental model.
  
  
  RESULTS
  Micro and macro LMs presented a mean diameter of 0.5 and 2.6 mm, respectively. Compared to controls, LMs at interval (1.1 mm) and macroscopic stage induced significant perfusion changes: a decrease of 42% (P=0.004) and 41% (P=0.029) in hepatic transit time and an increase of 292% (P=0.073) and 240% (P=0.001) in portal delay, respectively.
  
  
  CONCLUSIONS
  LMs with a mean diameter between 1.1 and 2.6 mm induced significant hepatic perfusion changes, detected by CT. Such detection may help to select patients and propose chemotherapy at the time of primary tumor resection.
authors.affiliation: Department of Colorectal Surgery, Beaujon Hospital (AP-HP), 100 boulevard du General Leclerc, 92118 Clichy, Paris, France; Research Unit Bichat-Beaujon, INSERM U773, Universite Paris VII (Denis Diderot), Paris, France. yves.panis@bjn.aphp.fr.
authors.forename: Caroline
authors.initials: C
authors.lastname: Hatwell
authors.forename: Magaly
authors.initials: M
authors.lastname: Zappa
authors.forename: Mathilde
authors.initials: M
authors.lastname: Wagner
authors.forename: Nicolas
authors.initials: N
authors.lastname: Michoux
authors.forename: Valérie
authors.initials: V
authors.lastname: Paradis
authors.forename: Valérie
authors.initials: V
authors.lastname: Vilgrain
authors.forename: Leon
authors.initials: L
authors.lastname: Maggiori
authors.forename: Yves
authors.initials: Y
authors.lastname: Panis
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000473:pathology*; D004195:Disease Models, Animal; D008102:Liver Circulation; D008113:Liver Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000556:secondary*; D008297:Male; D061206:Neoplasm Micrometastasis; D055420:Perfusion Imaging / Q000379:methods*; D011237:Predictive Value of Tests; D051381:Rats; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*; D047368:Tumor Burden