title: Sensitivity of double-phase helical CT during arterial portography for detection of hypervascular hepatocellular carcinoma.
abstract: OBJECTIVE
  The purpose of our work was to determine the usefulness of double-phase helical CT during arterial portography (CTAP) for the detection of hypervascular hepatocellular carcinoma (HCC).
  
  
  METHODS
  Eighty-four patients with 176 hypervascular HCC nodules underwent double-phase CTAP. Hypervascular HCCs were diagnosed by iodized oil CT after transcatheter arterial chemoembolization (TACE). The first-phase images were obtained 30 s after the initiation of injection of a nonionic iodinated contrast medium into the superior mesenteric artery or splenic artery, and the second-phase images were obtained after 70 s. These images were interpreted separately for detection of HCC.
  
  
  RESULTS
  The double-phase CTAP detected two nodules and six nodules that were missed by the first- and second-phase images, respectively. The sensitivity for hypervascular HCC nodules was 89% for the first phase, 91% for the second phase, and 93% for the first phase and second phase combined. The double-phase CTAP showed significantly superior sensitivity to the first-phase CTAP for detecting HCC nodules (p < 0.05). However, there was no statistically significant difference between the sensitivities of the double-phase CTAP and the second-phase CTAP. The positive predictive values of the double-phase images were inferior to those of either the first-phase or the second-phase images alone.
  
  
  CONCLUSIONS
  Double-phase helical CTAP was found to be no better than second-phase CTAP alone for the detection of hypervascular HCC nodules.
authors.affiliation: Department of Radiology, Osaka University Medical School, Suita-city, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Hori
authors.forename: T
authors.initials: T
authors.lastname: Murakami
authors.forename: T
authors.initials: T
authors.lastname: Kim
authors.forename: S
authors.initials: S
authors.lastname: Takahashi
authors.forename: H
authors.initials: H
authors.lastname: Oi
authors.forename: K
authors.initials: K
authors.lastname: Tomoda
authors.forename: Y
authors.initials: Y
authors.lastname: Narumi
authors.forename: H
authors.initials: H
authors.lastname: Nakamura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000628:therapy; D016461:Chemoembolization, Therapeutic; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods