Recommended iodine dose for multiphasic contrast-enhanced mutidetector-row computed tomography imaging of liver for assessing hypervascular hepatocellular carcinoma: multicenter prospective study in 77 general hospitals in Japan.
OBJECTIVE
To determine the recommended iodine dose of contrast material (CM) for hepatic arterial-dominant phase (HAP) and hepatic parenchymal phase (HPP) imaging to assess hypervascular hepatocellular carcinoma (HCC).


METHODS
This was a prospective study including 348 patients with hypervascular HCC in 77 hospitals as a postmarketing surveillance to investigate the effects of body weight-tailored dose of CM (300 mgI/mL of iohexol) for hepatic multiphasic contrast-enhanced multidetector-row computed tomography imaging. Informed consent was obtained from all patients who were enrolled. The tumor-to-liver contrast (TLC) of HAP images was assessed qualitatively (QL-TLC) and quantitatively (QT-TLC [HU]; computed tomography [CT] value of tumor-CT value of hepatic parenchyma). Minimal and sufficient QT-TLC were defined as CT values corresponding to the median and 75% of QL-TLC assigned with "good," respectively. The recommended iodine dose was estimated by the relationship between iodine dose (mgI/kg) and QT-TLC.


RESULTS
There was a good correlation between QL-TLC and QT-TLC. The recommended iodine dose of CM for HAP imaging was considered to be in the range of 567-647 mgI/kg based on minimal (33.7 HU) and sufficient QT-TLC (40.9 HU). Meanwhile, the recommended dose of CM for HPP imaging was 572 mgI/kg as a dose that gives hepatic enhancement more than 50 HU during HPP imaging.


CONCLUSIONS
The recommended iodine dose of CM for HAP and HPP imaging may be different, being 567-647 mgI/kg and 572 mgI/kg, respectively, in assessing hypervascular HCC.
Department of Radiology, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan. ichikawa@yamanashi.ac.jp
Tomoaki
T
Ichikawa
Masahiro
M
Okada
Hiroshi
H
Kondo
Hironobu
H
Sou
Takamichi
T
Murakami
Masayuki
M
Kanematsu
Shushi
S
Yoshikawa
Kazuhito
K
Shiosakai
Akiko
A
Hayakawa
Kazuo
K
Awai
Kengo
K
Yoshimitsu
Yasuyuki
Y
Yamashita
D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D003287:Contrast Media / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D005260:Female; D006769:Hospitals, General / Q000706:statistics & numerical data; D006801:Humans; D007472:Iohexol / Q000008:administration & dosage; D007564:Japan / Q000453:epidemiology; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D008297:Male; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D015995:Prevalence; D011856:Radiographic Image Enhancement / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000706:statistics & numerical data
D003287:Contrast Media; D007472:Iohexol
Computed tomography; contrast material; hepatocellular carcinoma; liver