Small hepatocellular carcinomas in patients with liver cirrhosis: potentials and limitations of contrast-enhanced power Doppler sonography.

Detection and characterization of focal liver lesions are critical for patients with liver cirrhosis. The potential of contrast-enhanced sonography in the characterization of focal liver lesions is well established in the literature. However, prospective studies in the assessment of patients with suspected hepatocellular carcinoma (HCC) in liver cirrhosis are rare. B-mode imaging often cannot differentiate small focal lesions in cirrhotic livers. Also, power Doppler is not capable of characterizing small focal lesions in cirrhosis. Contrast-enhanced sonography with a first-generation enhancer seems to improve the accuracy of diagnosis of small HCC. The differentiation of HCC and dysplastic nodules is notoriously difficult. In addition, other arterial hypervascularized liver lesions should be considered, depending on the clinical background. The limitations and drawbacks of contrast-enhanced sonography should be considered. All imaging methods are of limited value in the detection of solid liver lesions smaller than 1 cm.