title: MDCT of hypervascular hepatocellular carcinomas: a prospective study using contrast materials with different iodine concentrations.
abstract: OBJECTIVE
  The objective of our study was to investigate the effect of different iodine concentrations in contrast materials on the depiction of hypervascular hepatocellular carcinomas (HCCs) by MDCT.
  
  
  METHODS
  This prospective study involved 100 consecutive patients with chronic liver disease, including 27 patients with hypervascular HCCs. The first 50 patients received 100 mL of iopamidol at a concentration of 370 mg I/mL (group A) and the subsequent 50, 100 mL at 300 mg I/mL (group B); in both groups, the contrast material was administered at a rate of 3.0 mL/sec. Unenhanced scanning and four-phase enhanced scanning at 25, 40, 60, and 180 sec after the start of contrast injection were performed. The enhancement of the aorta, liver, and portal vein was measured during each phase. In addition, tumor-to-liver contrast was calculated for the 27 patients with hypervascular HCCs. Of the 27 patients with hypervascular HCCs, 15 were in group A and 12 were in group B.
  
  
  RESULTS
  During all phases, aortic enhancement was significantly greater in group A than group B (p < 0.01). Hepatic enhancement was significantly greater in group A than group B at 60 and 180 sec (both p < 0.01). There was no significant difference in hepatic enhancement between the two groups at 25 and 40 sec. Tumor-to-liver contrast was significantly greater in group A than group B during the late arterial phase (40 sec, p = 0.02), although there was no significant difference at 25, 60, and 180 sec.
  
  
  CONCLUSIONS
  Contrast materials with higher iodine concentration are more effective for depicting hypervascular HCCs on MDCT during the late arterial phase.
authors.affiliation: Department of Radiology, Kinki University School of Medicine, 377-2 Ohno-Higashi, Osaka-Sayama, Osaka 589-8511, Japan.
authors.forename: Yukinobu
authors.initials: Y
authors.lastname: Yagyu
authors.forename: Kazuo
authors.initials: K
authors.lastname: Awai
authors.forename: Masaaki
authors.initials: M
authors.lastname: Inoue
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Watai
authors.forename: Toshiko
authors.initials: T
authors.lastname: Sano
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Nishimura
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000000981:diagnostic imaging*; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007267:Injections; D007479:Iopamidol / Q000008:administration & dosage*; D008113:Liver Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D007479:Iopamidol