title: Differentiation of focal liver lesions using three-dimensional ultrasonography: retrospective and prospective studies.
abstract: OBJECTIVE
  To differentiate focal liver lesions based on enhancement patterns using three-dimensional ultrasonography (3D US) with perflubutane-based contrast agent.
  
  
  METHODS
  Two hundred and eighty two patients with focal liver lesions, including 168 hepatocellular carcinomas (HCCs), 63 metastases, 40 hemangiomas and 11 focal nodular hyperplasias (FNHs), were examined by 3D US with perflubutane-based contrast agent. Tomographic ultrasound images and sonographic angiograms were reconstructed. Among 282 lesions, enhancement patterns of 163 lesions between January 2007 and October 2007 were analyzed retrospectively. Then from November 2007 to May 2008, compared with contrast-enhanced (CE) 2D US, CE 3D US was performed on 119 lesions for prospective differential diagnosis. Sensitivity, specificity, area under receiver operating characteristic curve (A(z)) and inter-reader agreement were assessed.
  
  
  RESULTS
  With the tridimensional view, dominant enhancement patterns were revealed as diffuse enhancement or peripheral ring-like enhancement, followed with washout change for HCCs or metastases, respectively, and peripheral nodular enhancement or diffuse enhancement with spoke-wheel arteries, followed by persistent enhancement for hemangiomas or FNHs, respectively. At CE 3D US, the prospective differentiation of lesions showed sensitivity 92% (mean for two readers), specificity 91% and A(z) value 0.95 for HCCs, 84%, 97%, and 0.95 for metastases, 91%, 98%, and 0.98 for hemangiomas and 80%, 99%, and 0.99 for FNHs, respectively, while good to excellent inter-reader agreement was achieved. No significant difference exists between prospective diagnosis accuracy at CE 3D US and that at CE 2D US.
  
  
  CONCLUSIONS
  CE 3D US provides a spatial perspective for liver tumor enhancement, and could help in differentiating focal liver lesions.
authors.affiliation: Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Wen
authors.initials: W
authors.lastname: Luo
authors.forename: Kazushi
authors.initials: K
authors.lastname: Numata
authors.forename: Manabu
authors.initials: M
authors.lastname: Morimoto
authors.forename: Akito
authors.initials: A
authors.lastname: Nozaki
authors.forename: Michio
authors.initials: M
authors.lastname: Ueda
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kondo
authors.forename: Satoshi
authors.initials: S
authors.lastname: Morita
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Tanaka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D020518:Focal Nodular Hyperplasia / Q000000981:diagnostic imaging; D006391:Hemangioma / Q000000981:diagnostic imaging; D006801:Humans; D021621:Imaging, Three-Dimensional; D008107:Liver Diseases / Q000000981:diagnostic imaging*; D008113:Liver Neoplasms / Q000556:secondary / Q000648:ultrastructure; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012189:Retrospective Studies; D014463:Ultrasonography
chemical_list: D003287:Contrast Media