title: Aortic and Hepatic Contrast Enhancement During Hepatic-Arterial and Portal Venous Phase Computed Tomography Scanning: Multivariate Linear Regression Analysis Using Age, Sex, Total Body Weight, Height, and Cardiac Output.
abstract: OBJECTIVE
  We evaluated the effect of the age, sex, total body weight (TBW), height (HT) and cardiac output (CO) of patients on aortic and hepatic contrast enhancement during hepatic-arterial phase (HAP) and portal venous phase (PVP) computed tomography (CT) scanning.
  
  
  METHODS
  This prospective study received institutional review board approval; prior informed consent to participate was obtained from all 168 patients. All were examined using our routine protocol; the contrast material was 600 mg/kg iodine. Cardiac output was measured with a portable electrical velocimeter within 5 minutes of starting the CT scan. We calculated contrast enhancement (per gram of iodine: [INCREMENT]HU/gI) of the abdominal aorta during the HAP and of the liver parenchyma during the PVP. We performed univariate and multivariate linear regression analysis between all patient characteristics and the [INCREMENT]HU/gI of aortic- and liver parenchymal enhancement.
  
  
  RESULTS
  Univariate linear regression analysis demonstrated statistically significant correlations between the [INCREMENT]HU/gI and the age, sex, TBW, HT, and CO (all P < 0.001). However, multivariate linear regression analysis showed that only the TBW and CO were of independent predictive value (P < 0.001). Also, only the CO was independently and negatively related to aortic enhancement during HAP and to liver parenchymal enhancement when the contrast material injection protocol was adjusted for the TBW (P < 0.001).
  
  
  CONCLUSIONS
  By multivariate linear regression analysis only the TBW and CO were significantly correlated with aortic and liver parenchymal enhancement; the age, sex, and HT were not. The CO was the only independent factor affecting aortic and liver parenchymal enhancement at hepatic CT when the protocol was adjusted for the TBW.
authors.affiliation: From the *Department of Radiological Technology, Tsuchiya General Hospital, Nakajima-cho, Naka-ku; †Department of Diagnostic Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima; ‡Department of Diagnostic Radiology, Graduate School of Medical Sciences, §Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto; and ∥Department of Diagnostic Radiology, Tsuchiya General Hospital, Nakajima-cho, Naka-ku, Hiroshima, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Masuda
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakaura
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Funama
authors.forename: Toru
authors.initials: T
authors.lastname: Higaki
authors.forename: Masao
authors.initials: M
authors.lastname: Kiguchi
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Imada
authors.forename: Tomoyasu
authors.initials: T
authors.lastname: Sato
authors.forename: Kazuo
authors.initials: K
authors.lastname: Awai
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging / Q000503:physiopathology; D001827:Body Height / Q000502:physiology*; D001835:Body Weight / Q000502:physiology*; D002302:Cardiac Output / Q000502:physiology*; D003287:Contrast Media; D005260:Female; D006499:Hepatic Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D007472:Iohexol; D008297:Male; D008875:Middle Aged; D011169:Portal Vein / Q000000981:diagnostic imaging / Q000503:physiopathology; D011446:Prospective Studies; D011856:Radiographic Image Enhancement / Q000379:methods*; D012737:Sex Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol