Differentiation between benign and malignant hepatic lesions: utility of color stimulated acoustic emission with the microbubble contrast agent Levovist.
OBJECTIVE
This study was undertaken to determine whether the examination of color stimulated acoustic emission in the late phase of Levovist (SH U 508A; Schering AG, Berlin, Germany) enhancement is helpful in the discrimination between benign and malignant liver lesions.


METHODS
Fifty-six patients with focal hepatic lesions were examined. Diagnosis of the lesions was confirmed by liver biopsy, computed tomography, or scintigraphy. Thirty-one patients had malignant liver lesions: hepatocellular carcinoma (n = 14), cholangiocellular carcinoma (n = 1), metastasis (n = 14), and lymphoma (n = 2). Twenty-five patients had benign lesions: focal nodular hyperplasia (n = 8), hepatic adenoma (n = 1), focal hyposteatosis or hypersteatosis (n = 6), hemangioma (n = 7), and regenerative cirrhotic nodules (n = 3). After a delay of 5 to 10 minutes without scanning, the liver was examined by color stimulated acoustic emission with a fast sweep of 1 to 3 seconds.


RESULTS
All patients with homogeneous color stimulated acoustic emission in the late phase of Levovist enhancement had benign liver lesions (P < .001; specificity, 100%; sensitivity, 68%; positive predictive value, 100%; and negative predictive value, 79%). Eighty-one percent of the patients with nonenhancing lesions in the late phase surrounded by enhanced liver parenchyma had malignant liver lesions (P < .001; specificity, 72%; sensitivity, 94%; positive predictive value, 81%; and negative predictive value, 90%). Interobserver agreement (weighted kappa value) improved from 0.570 +/- 0.038 for baseline sonography to 0.918 +/- 0.028 for color stimulated acoustic emission sonography. The area under the receiver operating characteristic curves for color stimulated acoustic emission sonography (0.927) was significantly higher than for baseline sonography (0.739; P < .05).


CONCLUSIONS
Color stimulated acoustic emission in the late phase of Levovist enhancement has a high specificity and sensitivity for differentiation between benign and malignant focal liver lesions.
von Herbay
Alexandra
A
Department of Medicine, University of Düsseldorf, Düsseldorf, Germany.
Vogt
Christoph
C
Häussinger
Dieter
D
D000704:Analysis of Variance; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008107:Liver Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D008113:Liver Neoplasms / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011134:Polysaccharides; D012372:ROC Curve; D018608:Ultrasonography, Doppler
D003287:Contrast Media; D011134:Polysaccharides; C059891:SHU 508