title: Hepatocellular carcinoma: evaluation with biphasic, contrast-enhanced, helical CT.
abstract: OBJECTIVE
  To evaluate the added value of hepatic arterial-dominant phase (HAP) imaging to portal venous-dominant phase (PVP) imaging in patients with hepatocellular carcinoma (HCC) at computed tomography (CT).
  
  
  METHODS
  Sixty-six patients with proved HCC underwent biphasic contrast-enhanced CT. HAP and PVP images were obtained at 20-50 and 60-100 seconds, respectively. PVP images were evaluated for the number of HCC foci. Then, HAP images were reviewed to determine whether any additional HCCs were seen.
  
  
  RESULTS
  Three hundred twenty-six tumor foci were seen. HAP images depicted 309 foci (95%) and PVP images 268 (82%). In seven patients (11%), tumor was visible only on HAP images. During the HAP, tumors were hyperattenuating compared with liver in 26 patients, of mixed attenuation in 26, and hypoattenuating in 14 without correlation with histologic appearance. Portal vein thrombosis was identified in 17 of 21 patients on HAP images; in 12 patients, the thrombosis was diagnosed as malignant with neovascularity within the thrombus or diffuse thrombus enhancement.
  
  
  CONCLUSIONS
  Use of both HAP and PVP contrast-enhanced CT optimizes the evaluation of patients with or at risk for HCC.
authors.affiliation: Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA.
authors.forename: R L
authors.initials: RL
authors.lastname: Baron
authors.forename: J H
authors.initials: JH
authors.lastname: Oliver
authors.forename: G D
authors.initials: GD
authors.lastname: Dodd
authors.forename: M
authors.initials: M
authors.lastname: Nalesnik
authors.forename: B L
authors.initials: BL
authors.lastname: Holbert
authors.forename: B
authors.initials: B
authors.lastname: Carr
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging*; D003287:Contrast Media; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007482:Iothalamate Meglumine; D008113:Liver Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating; D011169:Portal Vein / Q000000981:diagnostic imaging; D012680:Sensitivity and Specificity; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014283:Triiodobenzoic Acids
chemical_list: D003287:Contrast Media; D014283:Triiodobenzoic Acids; C054871:ioversol; D007482:Iothalamate Meglumine