Abstract: Objective To analyze the hemodynamics of primary and metastatic small hepatic carcinomas on contrast-enhanced ultrasonography.
Methods Totally，210 primary and 93 metastatic small hepatic carcinoma lesions were examined by contrast-enhanced ultrasound. The enhancement patterns on the arterial，portal and delayed phases between the two groups were summarized. Results（1）In 303 small primary hepatic carcinoma lesions，contrast-enhanced ultrasound showed rapid enhancement in the arterial phase，and clearance in the portal and delay phase. While dynamic contrast-enhanced ultrasonography displayed that the enhancement peak time and the time from clearance of enhancement echo to hypoecho of metastatic small hepatic carcinoma were obviously earlier than those of primary hepatic carcinoma（P＜0.05）.（2） Contrast-enhanced ultrasound showed that 95.7％（201/210）of primary small hepatic carcinoma and 23％（2/93） of metastatic small hepatic carcinoma in the arterial phase were hyperechoic（P＜0.05），while hemodynamic changes of primary and metastatic small hepatic carcinomas had no statistical difference（P＞0.05）in the portal and delayed phase.（3）On the arterial contrast enhancement pattern，93.4％（196／210）lesions of primary small hepatic carcinoma showed overall uniformity，while that in metastatic small hepatic carcinoma was 35.5％（33／93）with statistic significance（P＜0.05）. And 54.8％ （51／93）lesions of metastatic small hepatic carcinoma showed peripheral annular enhancement or irregular enhancement，much higher than 5.2％（11／210）in primary small hepatic carcinoma （P＜0.05）. Conclusion Metastatic and primary small hepatic carcinomas present hyper-enhancement in the arterial phase of contrastenhanced ultrasound. However，they are different at enhancment pattern and the time from clearance of enhancement echo to hypoecho. Contrast-enhanced ultrasound has an important clinical value for diagnosis and differential diagnosis of primary and metastatic small hepatic carcinomas.