title: CT hepatic perfusion measurement: comparison of three analytic methods.
abstract: OBJECTIVE
  To compare the efficacy of three analytic methods, maximum slope (MS), dual-input single-compartment model (CM) and deconvolution (DC), for CT measurements of hepatic perfusion and assess the effects of extra-hepatic systemic factors.
  
  
  METHODS
  Eighty-eight patients who were suspected of having metastatic liver tumors underwent hepatic CT perfusion. The scans were performed at the hepatic hilum 7-77 s after administration of contrast material. Hepatic arterial and portal perfusions (HAP and HPP, ml/min/100 ml) and arterial perfusion fraction (APF, %) were calculated with the three methods, followed by correlation assessment. Partial correlation analysis was used to assess the effects on hepatic perfusion values by various factors such as age, sex, risk of cardiovascular diseases, arrival time of contrast material at abdominal aorta, transit time from abdominal aorta to hepatic parenchyma, and liver dysfunction.
  
  
  RESULTS
  Mean HAP of MS was significantly higher than DC. HPP of CM was significantly higher than MS and CM, and HPP of MS was significantly higher than DC. There was no significant difference in APF. HAP and APF showed significant and moderate correlations among the methods. HPP showed significant and moderate correlations between CM and DC, and poor correlation between MS and CM or DC. All methods showed weak correlations between HAP or APF and age or sex. Finally, MS showed weak correlations between HAP or HPP and arrival time or cardiovascular risks.
  
  
  CONCLUSIONS
  Hepatic perfusion values arrived at with the three methods are not interchangeable. CM and DC are less susceptible to extra-hepatic systemic factors.
authors.affiliation: Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017, Japan.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Kanda
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yoshikawa
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Ohno
authors.forename: Naoki
authors.initials: N
authors.lastname: Kanata
authors.forename: Hisanobu
authors.initials: H
authors.lastname: Koyama
authors.forename: Daisuke
authors.initials: D
authors.lastname: Takenaka
authors.forename: Kazuro
authors.initials: K
authors.lastname: Sugimura
mesh_terms: D000368:Aged; D000465:Algorithms; D001783:Blood Flow Velocity; D005260:Female; D006801:Humans; D008102:Liver Circulation; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging* / Q000503:physiopathology; D055420:Perfusion Imaging / Q000379:methods*; D011856:Radiographic Image Enhancement / Q000379:methods; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*