title: Differentiation between true focal liver lesions and pseudolesions in patients with fatty liver: evaluation of helical CT criteria.
abstract: OBJECTIVE
  To determine the potential of helical CT for differentiating true lesions from pseudolesions in patients with fatty liver.
  
  
  METHODS
  Helical CT of 44 patients with diffuse fatty liver (22 with true lesions; 22 with pseudolesions) were reviewed by two observers with regard to morphological features of visible lesions. Univariate analysis was used to detect discriminating criteria for the diagnosis of true lesions.
  
  
  RESULTS
  Interobserver agreement was excellent for 9/10 morphological criteria (kappa = 0.831-1). True lesions were more frequently distant from the liver capsule (50.00% vs. 4.55%), located in the right lobe (72.73% vs. 31.82%), round (86.36% vs. 54.55%), heterogeneous (27.27% vs. 0.00%) and had ill-defined margins (40.91% vs. 13.64%) compared with pseudolesions (P < 0.05). Using univariate analysis, a location distant from the liver capsule was the most discriminating variable to differentiate between true and pseudolesions (P = 0.0060). Hyperattenuating content and round shape were the most sensitive criteria (sensitivity = 90.91% and 86.36%, respectively) for the diagnosis of true lesions, and heterogeneity, vascular displacement and encapsulation were the three most specific ones (specificity = 100.00%). Best accuracy was obtained with an association of the three variables (accuracy = 86.36%).
  
  
  CONCLUSIONS
  Helical CT provides objective and discriminating morphological criteria to differentiate between true lesions and pseudolesions in patients with fatty liver.
authors.affiliation: Departments of Abdominal Imaging, Lariboisière Hospital-AP-HP-GHU Nord and University Paris 7, Paris, France. philippe.soyer@lrb.aphp.fr
authors.forename: Philippe
authors.initials: P
authors.lastname: Soyer
authors.forename: Marc
authors.initials: M
authors.lastname: Sirol
authors.forename: Yann
authors.initials: Y
authors.lastname: Fargeaudou
authors.forename: Florent
authors.initials: F
authors.lastname: Duchat
authors.forename: Lounis
authors.initials: L
authors.lastname: Hamzi
authors.forename: Mourad
authors.initials: M
authors.lastname: Boudiaf
authors.forename: Mounir
authors.initials: M
authors.lastname: Aout
authors.forename: Youcef
authors.initials: Y
authors.lastname: Guerrache
authors.forename: Eric
authors.initials: E
authors.lastname: Vicaut
authors.forename: Roland
authors.initials: R
authors.lastname: Rymer
mesh_terms: D003937:Diagnosis, Differential; D005234:Fatty Liver / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D036542:Tomography, Spiral Computed