Evaluation of liver masss lesions with late pahse "Pulse Inversion" harmonic ultrasonograph using levovist

Purpose: The comparison of PIH US during the late phase of Levovist with conventional US and spiral CT for hepatic lesion detection and differential diagnosis. Material and methods: Thirty patients with proved or suspected liver masses (ages between 35-77) were enrolled in this study. All patients underwent conventional US, contrast enhanced PIH US, contrast enhanced triphasic spiral CT examinations consequtively. Additionally four patients were also examined with contrast enhanced dynamic liver NIRI. Two readers experienced in hepatobiliary US, who had no knowledge about patients, evaluated pre and post contrast images according to echogenicity, conspicuity, number, smallest size and rim sign of lesions. CT and MRI examinations were evaluated by two other radiologist who also had no information about patients. Statistical analysis were performed with 'SPSS for WINDOWS' programme and evaluations were tested by Chi-square and Wilcoxon tests. Differences with a p value less than 0.05 were considered statistically significant. Results: Fifteen malign (13 metastases, two HCC), 15 benign ( 10 hemangioma and five focal fatty changes) lesions were detected. After IV contrast agent administration in 13/15 of the malign lesions echogenicity decreased while conspicuity increased. In 14/15 of the benign lesions decrease in echogenity was not observed and their conscipuity decreased. Rim sign was found in eight patients with hepatic metastases. We have detected a significant increase in the number of lesions with PIH US (average n=5.54) than conventional US ( average n=2.46) (p<0.05). There was no significant difference between the average number of lesions observed with PIH US and spiral CT. The median smallest diameter of the lesions shown with PIH US (5mm) was significantly lower than with spiral CT (15mm) (p<0.05), while no significant difference was found between PIH US (5mm) and conventional US (10mm). Conclusion: PIH US is superior to conventional US in the evaluation of number, smallest size and differential diagnosis of liver lesions. Larger series are needed to compare PIH US and spiral CT. We think that PIH US is equivalent to CT and it can replace the expensive or radiation using modalities especially in the differential diagnosis and staging of malignancies.