Comparison between color power Doppler ultrasound with echo-enhancer and spiral computed tomography in the evaluation of hepatocellular carcinoma vascularization before and after ablation procedures

OBJECTIVE: Use of new echo enhancers capable of passing the lung filter has extended the clinical applications of color power Doppler flow imaging in many diseases and appears promising in the study of neoplasm vascularizatio n. Levovist (Shering, Berlin Germany) is an ultrasound contrast agent conta ining galactose microbubbles suspended in palmitic oil. The sensitivity of Levovist-enhanced color power Doppler was compared to that of standard colo r power Doppler and contrast-enhanced spiral computed tomography (CT) in th e detection of vascular signals in hepatocellular carcinoma. METHODS: We examined 29 hepatocellular carcinoma nodules in cirrhotic liver s that had appeared avascular on unenhanced color power Doppler. Color powe r Doppler studies were repeated with and without Levovist enhancement befor e (15 examinations) and/or after (23 examinations) percutaneous ablation pr ocedures. Findings (vascularized vs nonvascularized) were compared to those obtained with contrast-enhanced spiral computed tomography (gold standard) performed no more than 24 h after each of the 38 Doppler examinations. RESULTS:In pretreatment studies, Levovist-enhanced power Doppler correctly revealed vascularization in 12 of 15 lesions that had appeared avascular wi thout echo enhancement and confirmed the avascularity of one other nodule; the remaining two, which appeared avascular on contrast-enhanced Doppler, d isplayed vascularization on the spiral CT examination. Levovist-enhanced po wer Doppler was fully concordant with spiral CT findings in all of the post treatment examinations. CONCLUSION: Considering the absence of false positive results in this study , echo-enhanced color power Doppler can be considered reliable in diagnosin g incomplete necrosis of hepatocellular carcinomas after percutaenous ablat ion. Spiral computed tomography can thus be reserved for those cases in whi ch the enhanced power Doppler examination reveals no evidence of vascularit y. (C) 2001 by Am. Cell. of Gastroenterology.