title: Vascularization and perfusion of hepatocellular carcinoma: assessment with contrast-enhanced ultrasound using perflutren protein-type A microspheres.
abstract: OBJECTIVE
  To assess the vascularization and the perfusion within hepatocellular carcinoma (HCC) including treatment-related changes with contrast-enhanced (CE) ultrasound (US).
  
  
  METHODS
  Twenty-six biopsy-verified HCC lesions (size between 2.5-8 cm, median 3.8 cm) in 20 patients were examined with unenhanced and CE vascular US techniques immediately before selective angiography for transarterial chemoembolization (TACE) as well as immediately after TACE using all of the following modalities: color-coded Doppler sonography (CCDS), power Doppler imaging (PDI), CE pulse inversion harmonic imaging with PDI (PIHI+PDI), and CE coded harmonic angiography (CHA). In CE US studies, perflutren protein-type A microspheres were administered as contrast agent in a single 0.5 ml i.v. bolus diluted in 20 ml 0.9% NaCl. Selective arteriograms and CE computed tomographies were taken for reference purposes. The Wilcoxon test was used for statistical analysis.
  
  
  RESULTS
  Intratumoral vessels could be visualized before TACE in 11/26 lesions (42%) with CCDS; in 15/26 (58%) with PDI; in 23/26 (88%) with CE CHA; in 26/26 (100%) with CE PIHI+PDI. Following TACE, the sensitivities were calculated as follows: CCDS 33%; PDI 55%; CE CHA 77%; and CE PIHI+PDI 100%. The corresponding negative predictive values were 74% for CCDS; 81% for PDI; 89% for CE CHA and 100% for CE PIHI+PDI. During the capillary phase, contrast enhancement could be observed in the CHA mode only.
  
  
  CONCLUSIONS
  CE US by means of PIHI+PDI and CHA enables reliable visualization of residual tumor following TACE equivalent to that which is attained with angiography and Contrast Harmonic Imaging with Power Doppler, if perflutren microspheres are used as contrast agent in a single low-dose bolus.
authors.affiliation: Institute of Diagnostic Radiology, Passau Hospital - Teaching Hospital of the University of Regensburg, Germany.
authors.forename: Ernst Michael
authors.initials: EM
authors.lastname: Jung
authors.forename: Reinhard
authors.initials: R
authors.lastname: Kubale
authors.forename: Karl-Peter
authors.initials: KP
authors.lastname: Jungius
mesh_terms: D000328:Adult; D000368:Aged; D001808:Blood Vessels / Q000000981:diagnostic imaging*; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000628:therapy; D016461:Chemoembolization, Therapeutic; D003287:Contrast Media; D003952:Diagnostic Imaging / Q000379:methods / Q000592:standards; D005466:Fluorocarbons; D006801:Humans; D008863:Microspheres; D008875:Middle Aged; D011237:Predictive Value of Tests; D015424:Reperfusion; D012680:Sensitivity and Specificity; D013205:Staphylococcal Protein A; D014463:Ultrasonography / Q000379:methods* / Q000592:standards
chemical_list: D003287:Contrast Media; D005466:Fluorocarbons; D013205:Staphylococcal Protein A; C042852:perflutren