title: Characterization of hyperechoic focal liver lesions: quantitative evaluation with pulse inversion harmonic imaging in the late phase of levovist.
abstract: OBJECTIVE
  The aim of this study was to evaluate hyperechoic focal liver lesions with pulse inversion harmonic imaging in the late phase of SH U 508A (Levovist; Schering AG, Berlin, Germany) and to determine whether quantitative evaluation improves the characterization of the lesions.
  
  
  METHODS
  Twenty-six patients with hyperechoic liver lesions were enrolled in this study. Pulse inversion harmonic imaging was performed before and after administration of Levovist. Scan data were digitally stored, and each lesion was analyzed with a personal computer-based quantification package. All lesions were confirmed by histologic or triphasic spiral computed tomographic examinations. The intensity was measured in decibels in regions of interest drawn within the lesion and surrounding liver parenchyma. The lesion-liver ratios were than calculated. After contrast agent administration, a ratio equal to or greater than 1 was presumed benign, whereas a ratio of less than 1 was considered malignant.
  
  
  RESULTS
  Nine malignant (7 metastases, 1 hepatocellular carcinoma, and 1 cholangiocarcinoma) and 17 benign (14 hemangioma, 1 focal nodular hyperplasia, 1 focal fatty change, and 1 inflammatory pseudotumor) hyperechoic lesions were quantitatively evaluated. All malignant (n = 9) and 2 benign lesions (1 hemangioma and 1 inflammatory pseudotumor) had ratios of less than 1. In 15 of 17 benign lesions, the ratios were equal to or greater than 1. The intensity ratios calculated for benign and malignant lesions showed a statistically significant difference (P < .05).
  
  
  CONCLUSIONS
  Pulse inversion harmonic imaging with quantitative evaluation facilitates the differential diagnosis of hyperechoic focal liver lesions. A lesion-liver ratio equal to or greater than 1 predicts a benign nature, assuming that malignant lesions show a ratio of less than 1.
authors.affiliation: Department of Radiology, Gazi University School of Medicine, 1 Kat, 06510 Besevler, Ankara, Turkey. celik72@yahoo.com
authors.forename: Halil
authors.initials: H
authors.lastname: Celik
authors.forename: Hakan
authors.initials: H
authors.lastname: Ozdemir
authors.forename: Cem
authors.initials: C
authors.lastname: Yücel
authors.forename: Serap
authors.initials: S
authors.lastname: Gultekin
authors.forename: Suna O
authors.initials: SO
authors.lastname: Oktar
authors.forename: Mehmet
authors.initials: M
authors.lastname: Arac
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging*; D008107:Liver Diseases / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011134:Polysaccharides; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography / Q000379:methods
chemical_list: D003287:Contrast Media; D011134:Polysaccharides; C059891:SHU 508