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

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. DOI: 10.11855/j.issn.0577-7402.2016.08.05