射频消融肝蒂毁损联合肝动脉阻断在精准肝切除中的作用

Role of ultrasound-guided radiofrequency ablation for hepatic pedicle lesioning combined with temporary occlusion of the hepatic artery in precise liver resection

目的通过建立动物精准肝切除模型来评估射频消融肝蒂毁损联合肝动脉阻断在精准肝切除中应用的安全性及可行性。方法选取健康广西巴马小型猪6头,每头动物均选取S3、S5、S6段作为目标肝段,超声引导下射频消融肝蒂毁损,同时行肝动脉暂时阻断,根据缺血边界完整切除肝段。观察指标为动物术后存活情况、动物肝功能变化、肝段血管血流指标以及肝段门脉、动脉、胆管病理变化情况。结果术后死亡率及并发症发生率为0,所有动物术后14d肝功能均恢复正常。所有肝段显色效果明显。射频消融后所有目标肝段门静脉的血流速度为均0,动脉的血流速度为15.1±15.4cm/s,较射频前显著降低(P=0.000);所有保留肝段的门脉及动脉血流速度在射频前、射频后、术后14d无显著变化。连续切片显微观察肝段门脉、动脉及胆管平均毁损长度分别为1.7±0.5、1.4±0.4、1.6±0.4cm。结论超声引导下射频消融肝蒂毁损联合肝动脉暂时阻断技术安全、可靠,可以更好地消除残存动脉血流对显色效果的影响。为避免损伤邻近肝蒂,电极插入部位距肝蒂分叉处的垂直距离应至少为1.5cm。

Objective To evaluate the safety and feasibility of radiofrequency ablation（RFA） for hepatic pedicle lesioning in combination with hepatic artery clamping for precise liver resection by establishing a model of precise liver resection in animals. Methods Six healthy Guangxi Bama miniature pigs were selected for this study, and S3, S5 and S6 used as target hepatic segments. The hepatic pedicles were lesioned by radioablation under ultrasound guidance. The hepatic artery was clamped temporarily at the time of radioablation. Three segments（S3, S5 and S6） were resected on each pig. The main outcome measures included the local and general tolerance, the change of blood flow parameters of each segmental arterial and portal branches, and the microscopic appearance of the segmental arterial, portal and biliary tract branches. Results There was no any complication or death following RFA application, and the liver function was restored to normal 14 days after the operation in all animals. Demarcation areas were clear in all target hepatic segments. The blood flow velocity of the portal branches was 0cm/s in all the target hepatic segments after RFA. The arterial blood flow velocity was 15.1±15.4cm/s, which was significantly lower compared with that before RFA（P〉0.000）. There was no difference in the flow rate of the unaffected segmental vessels following RFA. The mean ablated length of segmental portal, arterial and biliary tract branches was 1.7±0.5cm, 1.4±0.4cm, 1.6±0.4cm, respectively. Conclusions The technique is expedient, safe and effective. Simultaneous temporary occlusion of the hepatic artery adds further benefit. The probe needs to be at least 1.5cm away from non targeted structures to avoid unintended thermal injury.