Background: Early diagnosis of hepatocellular carcinoma (HCC) is extremely important because surgical resection and local ablation therapy are undoubtfully the most effective treatment regimen. Recent advances in sonographic techniques have risen the question of sonography utility. The scope of this investigation was to assess the detection accuracy of tumor vascularity in HCC by contrastenhanced,
wide-band phase inversion (PI) power Doppler sonography.
Material and Methods: Twenty-one patients were examined with 21 nodules (16 hypo-, 2 iso-, 3 hyperechoic nodules). The presence of hepatocellular carcinoma was confirmed by fine-needle biopsy results in 16 nodules, and the diagnosis in the remaining tumors was based on imaging findings and tumor markers. All patients, prior to enhanced sonography, had undergone both the native B-mode and tissue harmonic imaging mode sonography, color Doppler, and power Doppler examinations.
Results: Three patients were excluded. 18 nodules evaluation by contrast-enhanced, wide-band PI power Doppler US revealed tumor vessels in 100% cases in arterial phase. The characteristic chaotic pattern of lesions vascularity was evidently pronounced. Rapid increase of enhancement during the arterial and slow decrease of enhancement during the portal phase were the special features of HCCs helping in making the final diagnosis. Power Doppler sonography detection rates were 14 cases (77%).
Conclusions: Based on our results we can recommend wide-band, phase inversion power Doppler sonography in the differential diagnosis of HCC by visualizing characteristic behavior of enhancement pattern in the most cases.

Keywords: hepatocellular carcinoma, echo-enhanced, wide-band phase inversion power Doppler sonography, Levovist contrast agent, Biopsy, Fine-Needle, Carcinoma, Hepatocellular - ultrasonography, Contrast Media - diagnostic use, Diagnosis, Differential, Liver Neoplasms - ultrasonography, Neovascularization, Pathologic - ultrasonography, Ultrasonography, Doppler, Color - methods