title: Spiral CT for the detection of hepatocellular carcinomas:relative value of arterial- and late-phase scanning.
abstract: BACKGROUND
  Spiral computed tomography (CT) can image the liver during arterial and late phases of contrast and optimize the evaluation of hypervascular tumor. The objective of this study was to evaluate the relative value of arterial- and late-phase spiral CT in the detection of hepatocellular carcinomas.
  
  
  METHODS
  Fifty-eight patients with hepatocellular carcinomas underwent two-phase spiral CT examination with 10-mm collimation at 10 mm/s table speed (Siemens Somatom Plus S), and 120 mL of contrast material (36 g iodine) was injected at the rate of 3 mL/s. CT images of hepatic arterial and late phases were obtained with a 35-s and 180-s delay, respectively.
  
  
  RESULTS
  In 58 patients, 111 hepatocellular carcinoma lesions were seen. The arterial phase detected 93 (84%) and the late phase 75 (68%) lesions (p < 0.01). The arterial phase detected more lesions in 11 patients, and the late phase detected more in two patients and an equal number in 45 patients. If lesions larger than 2 cm are excluded, the arterial phase detected 40 (74%) and the late phase 21 (39%) of 54 lesions (p < 0.001).
  
  
  CONCLUSIONS
  The arterial phase of spiral CT greatly improves the detection of hepatocellular carcinoma when compared with the late phase.
authors.affiliation: Department of Radiology, Seoul National University Hospital, 28, Yongon-dong, Chongno-Gu, Seoul, 110-744, Korea.
authors.forename: B I
authors.initials: BI
authors.lastname: Choi
authors.forename: J M
authors.initials: JM
authors.lastname: Cho
authors.forename: J K
authors.initials: JK
authors.lastname: Han
authors.forename: D S
authors.initials: DS
authors.lastname: Choi
authors.forename: M C
authors.initials: MC
authors.lastname: Han
mesh_terms: D000328:Adult; D000368:Aged; D000792:Angiography; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000000981:diagnostic imaging*; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006499:Hepatic Artery; D006801:Humans; D007275:Injections, Intravenous; D007455:Iodine / Q000008:administration & dosage; D007459:Iodized Oil / Q000008:administration & dosage; D007483:Iothalamic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives; D008113:Liver Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011856:Radiographic Image Enhancement / Q000379:methods*; D016037:Single-Blind Method; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007483:Iothalamic Acid; D007459:Iodized Oil; D007455:Iodine; C019462:meglumine ioglicinate