title: [Native and signal-enhanced power Doppler sonography for characterization of liver lesions].
abstract: OBJECTIVE
  To evaluate the characterisation of liver lesions using power Doppler sonography before and after intravenous injection of the ultrasound contrast agent Levovist.
  
  
  METHODS
  39 patients with 41 liver lesions (10 haemangiomas, 2 focal nodular hyperplasias (FNH), 2 focal fatty infiltrations, 1 echinococcal lesion, 11 hepatocellular carcinomas, 14 metastases and one cholangiocarcinoma) were evaluated prospectively. Power Doppler images before and after intravenous injection of the ultrasound contrast agent Levovist were analysed by two radiologists and one gastroeterologist, who subjectively classified the distribution (peripheral, central, diffuse) and amount (none, minimal, moderate and strong) of flow pattern in each sonographic examination. Histological verification was obtained in all liver lesions, except in haemangiomas, where MR imaging and in one FNH where scintigraphy was regarded as sufficient proof.
  
  
  RESULTS
  On the whole, power Doppler sonography after contrast injection was superior to unenhanced power Doppler-sonography in 20 liver lesions and equal in 7. After contrast injection, previously visible flow was enhanced in 14 patients, in 6 lesions flow was detected, which was not seen before in the power mode. Moderate or strong flow signals were detected before contrast injection in 8/26, post contrast injection in 18/26 malignant tumours. Contrawise, 13/15 benign lesions did show any or only minimal flow signals before and 10/15 after contrast injection.
  
  
  CONCLUSIONS
  Intratumoural flow signals favour a malignant tumour. The absence of flow signals is a frequent finding in benign lesions but does not rule out malignancy.
authors.affiliation: Radiologische Universitätsklinik Bonn.
authors.forename: H
authors.initials: H
authors.lastname: Strunk
authors.forename: G
authors.initials: G
authors.lastname: Stuckmann
authors.forename: E
authors.initials: E
authors.lastname: Fröhlich
authors.forename: J
authors.initials: J
authors.lastname: Textor
authors.forename: K
authors.initials: K
authors.lastname: Wilhelm
authors.forename: N
authors.initials: N
authors.lastname: Hortling
authors.forename: J
authors.initials: J
authors.lastname: Remig
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging*; D003287:Contrast Media; D003937:Diagnosis, Differential; D004444:Echinococcosis, Hepatic / Q000000981:diagnostic imaging; D005234:Fatty Liver / Q000000981:diagnostic imaging; D006391:Hemangioma / Q000000981:diagnostic imaging*; D006801:Humans; D006965:Hyperplasia; D008099:Liver / Q000000981:diagnostic imaging* / Q000473:pathology*; D008107:Liver Diseases / Q000000981:diagnostic imaging*; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary; D011134:Polysaccharides; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D019780:Technetium Tc 99m Lidofenin; D018608:Ultrasonography, Doppler / Q000379:methods*
chemical_list: D003287:Contrast Media; D011134:Polysaccharides; D019275:Radiopharmaceuticals; C059891:SHU 508; D019780:Technetium Tc 99m Lidofenin
vernacular_title: Native und signalverstärkte Power-Doppler-Sonographie zur Charakterisierung von Leberherden.