摘要

Objectives-The purpose of this study was to explore the effects of a microbubble contrast agent (SonoVue; Bracco SpA, Milan, Italy) on the spread of gas generated by heating during radiofrequency ablation in vivo. Methods-Radiofrequency ablation was performed with or without SonoVue on 2 areas per rabbit liver in 20 rabbits under sonographic guidance. They were divided into groups 1 and 2 on the basis of ablation with and without SonoVue. In group 1, SonoVue (0.05 mL/kg) was injected as an intravenous bolus. After radiofrequency ablation, 3 orthogonal diameters of hyperechogenicity and defects of enhancement on contrast-enhanced sonography were measured sonographically. Coagulated zones and ablation times were also evaluated. Results-There were no significant differences in the sizes of the hyperechoic areas, defects, or coagulated zones between the groups (P>.05). However, the total number of ablations with clearly visualized hyperechogenicity was 15 in group 1 versus 7 in group 2, as opposed to ablations with partial or not clearly visualized hyperechogenicity (P<.05). A comparison between hyperechoic and pathologic volumes provided correlation values of r(2) = 0.803 and r(2) = 0.624 for groups 1 and 2, respectively. In addition, the ablation time for group 1 was significantly shorter (P<.05). Conclusions-A microbubble agent would not change the size of the ablated area, but it can improve prediction of ablated areas and reduce the ablation time for achieving the same effects. Therefore, it might be useful to prevent unfavorable ablation of adjacent organs and vessels.