title: US characterization of focal hepatic lesions with intermittent high-acoustic-power mode and contrast material.
abstract: OBJECTIVE
  This study was performed to determine whether ultrasound (US) performed with SonoVue, a contrast agent that contains microbubbles filled with sulfur hexafluoride vapor, depicts differential patterns of contrast enhancement in focal hepatic lesions.
  
  
  METHODS
  Forty focal hepatic lesions (15 hepatocellular carcinomas [HCCs], 10 metastases, 11 hemangiomas, and four focal nodular hyperplasias) in 39 patients were evaluated by means of US, color Doppler US, and contrast-enhanced US performed by using intermittent high-acoustic-power mode. Contrast-enhanced helical computed tomography (11 patients) and US-guided fine needle aspiration (28 patients) were used as reference procedures. Contrast enhancement patterns were defined by means of both subjective and objective analysis, and baseline and contrast-enhanced US scans were reviewed offline.
  
  
  RESULTS
  Thirteen of 15 HCCs, eight of 10 metastases, and all four hemangiomas with an atypical pattern at baseline US were correctly characterized after SonoVue injection. Two of 15 HCCs and two of 10 metastases remained indeterminate, with no characteristic baseline or contrast-enhanced patterns identified. Baseline US was essential in characterizing all hemangiomas with a typical pattern (n = 7), and color Doppler US with spectral analysis of tumoral vessels was essential in characterizing focal nodular hyperplasia. The percentage of diagnostic agreement with reference procedures was significantly increased (P < .001) for contrast-enhanced US compared with baseline US.
  
  
  CONCLUSIONS
  Characteristic patterns of US contrast enhancement with SonoVue help in characterizing and differentiating focal hepatic lesions.
authors.affiliation: Department of Radiology, Cattinara Hospital, University of Trieste, Strada di Fiume 447, Trieste 34149, Italy.
authors.forename: Emilio
authors.initials: E
authors.lastname: Quaia
authors.forename: Michele
authors.initials: M
authors.lastname: Bertolotto
authors.forename: Loretta
authors.initials: L
authors.lastname: Calderan
authors.forename: Elisa
authors.initials: E
authors.lastname: Mosconi
authors.forename: Roberto Pozzi
authors.initials: RP
authors.lastname: Mucelli
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging*; D003287:Contrast Media; D005260:Female; D020518:Focal Nodular Hyperplasia / Q000000981:diagnostic imaging*; D006391:Hemangioma / Q000000981:diagnostic imaging*; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary; D008297:Male; D008875:Middle Aged; D010743:Phospholipids; D011446:Prospective Studies; D013459:Sulfur Hexafluoride; D018615:Ultrasonography, Doppler, Color
chemical_list: D003287:Contrast Media; D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride