title: Surgically staged focal liver lesions: accuracy and reproducibility of dual-phase helical CT for detection and characterization.
abstract: OBJECTIVE
  To assess the accuracy and reproducibility of dual-phase helical computed tomography (CT) in enabling preoperative detection and characterization of surgically staged focal liver lesions.
  
  
  METHODS
  Surgically and histopathologically proven liver lesions were evaluated by three experienced CT readers. These lesions were present in 77 patients who underwent dual-phase helical CT. Images were interpreted separately by the three blinded reviewers. Each lesion was graded on a nine-point scale of confidence, with 1 being definitely benign, 9 being definitely malignant, and 5 being indeterminate. The chi2 test was used to determine if the distribution of lesion classifications was different between readers.
  
  
  RESULTS
  There was a total of 237 lesions: 73 were benign and 164 were malignant. Sensitivity for lesion detection was 69%, 70%, and 71% for the three reviewers, respectively. Specificity was 91%, 86%, and 90%, and the area under the curve for the alternative-free response receiver operating characteristic curve was 0.84, 0.83, and 0.85, respectively. The difference in the distributions of lesion classification between the three reviewers was not statistically significant (P =.67) as determined by chi2 analysis.
  
  
  CONCLUSIONS
  Dual-phase CT has sensitivity of 69%-71% and high specificity (86%-91%) in enabling the detection and characterization of focal liver lesions. Interpretation is highly reproducible, as there is minimal variation between experienced reviewers.
authors.affiliation: Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins Hospital, 600 N Wolfe St, Rm 100, Baltimore, MD 21287, USA. ikamel@jhmi.edu
authors.forename: Ihab R
authors.initials: IR
authors.lastname: Kamel
authors.forename: Michael A
authors.initials: MA
authors.lastname: Choti
authors.forename: Karen M
authors.initials: KM
authors.lastname: Horton
authors.forename: H J V
authors.initials: HJ
authors.lastname: Braga
authors.forename: Bernard A
authors.initials: BA
authors.lastname: Birnbaum
authors.forename: Elliot K
authors.initials: EK
authors.lastname: Fishman
authors.forename: Richard E
authors.initials: RE
authors.lastname: Thompson
authors.forename: David A
authors.initials: DA
authors.lastname: Bluemke
mesh_terms: D005260:Female; D020518:Focal Nodular Hyperplasia / Q000000981:diagnostic imaging*; D006801:Humans; D008107:Liver Diseases / Q000000981:diagnostic imaging*; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D036542:Tomography, Spiral Computed