title: Determination of optimal intravenous contrast agent iodine dose for the detection of liver metastasis at 80-kVp CT.
abstract: OBJECTIVE
  To determine the optimal iodine mass (IM) to achieve a 50-HU increase in hepatic attenuation for the detection of liver metastasis based on total body weight (TBW) or body surface area (BSA) at 80-kVp computed tomography (CT) imaging of the liver.
  
  
  METHODS
  One-hundred and fifty patients who underwent contrast-enhanced CT at 80-kVp were randomised into three groups: 0.5 gI/kg, 0.4 gI/kg and 0.3 gI/kg. Portal venous phase images were evaluated for hepatic parenchymal enhancement (∆HU) and visualisation of liver metastasis. Iodine mass per BSA (gI/m(2)) calculated in individual patients were evaluated.
  
  
  RESULTS
  Mean ∆HU for the 0.5 gI/kg group (84.2 HU) was higher than in the 0.4 gI/kg (66.1 HU) and 0.3 gI/kg (53.7 HU) groups (P < 0.001). Linear correlation equations between ∆HU and IM per TBW or BSA are ∆HU = 7.0 + 153.0 × IM/TBW (r = 0.73, P < 0.001) and ∆HU = 11.4 + 4.0 × IM/BSA (r = 0.75, P < 0.001), respectively. The three groups were comparable for the visualisation of hepatic metastases.
  
  
  CONCLUSIONS
  The iodine mass to achieve a 50-HU increase in hepatic attenuation at 80-kVp CT was estimated to be 0.28 gI/kg of body weight or 9.6 gI/m(2) of body surface area.
  
  
  CONCLUSIONS
  • Hepatic enhancement is expressed as ∆HU = 7.0 + 153.0 × IM [g]/TBW [kg]. • Hepatic enhancement is expressed as ∆HU = 11.4 + 4.0 × IM [g]/BSA [m(2)]. • Essential iodine dose at 80-kVp CT was 0.28 gI/kg or 9.6 gI/m(2).
authors.affiliation: Department of Radiology, Gifu University Hospital, 1-1 Yanagido, 501-1194, Gifu, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Goshima
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kanematsu
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Noda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kondo
authors.forename: Haruo
authors.initials: H
authors.lastname: Watanabe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawada
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kawai
authors.forename: Yukichi
authors.initials: Y
authors.lastname: Tanahashi
authors.forename: Kyongtae T
authors.initials: KT
authors.lastname: Bae
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001830:Body Surface Area; D001835:Body Weight; D003287:Contrast Media / Q000008:administration & dosage; D003937:Diagnosis, Differential; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007275:Injections, Intravenous; D007455:Iodine / Q000008:administration & dosage; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D009367:Neoplasm Staging; D011379:Prognosis; D011446:Prospective Studies; D015203:Reproducibility of Results
chemical_list: D003287:Contrast Media; D007455:Iodine