高强聚焦超声消融兔腹主动脉旁肝肿瘤对腹主动脉的影响

Impact of ablation of liver tumor adjacent to abdominal aorta using MRI-guided high intensity focused ultrasound in rabbits

目的观察高强聚焦超声(HIFU)消融兔腹主动脉旁肝肿瘤对腹主动脉的影响。方法对43只实验兔建立腹主动脉旁VX2肝肿瘤模型,于MR引导下行HIFU消融肿瘤,通过彩色多普勒超声观察消融前、消融后即刻、2h和6h腹主动脉充盈情况,测量血流峰值血流速(PSV)、平均血流速度(Vm)、平均血流量、阻力指数(RI)和搏动指数(PI)变化;病理观察消融前及消融后即刻腹主动脉的改变情况。结果共对40只实验兔成功建立腹主动脉旁肝肿瘤模型。消融后即刻腹主动脉血流通畅,未见明显狭窄、塌陷或闭塞。较之消融前,消融后即刻腹主动脉PSV、Vm和平均血流量明显减慢,RI和PI明显上升(P均<0.05),之后逐渐恢复,于消融后6h恢复至消融前水平(P均>0.05)。病理学检查示消融后即刻腹主动脉无损伤。结论 HIFU消融腹主动脉旁肿瘤可一过性改变腹主动脉血流动力学,而对管壁无明显损伤。

Objective To explore the impact of ablation of liver tumor adjacent to the abdominal aorta using MRI-guided high intensity focused ultrasound （HIFU） in rabbits. Methods Models of VX2 liver tumor adjacent to abdominal aorta were established in 43 rabbits. The ablation of the liver tumor was performed using MRI-guided HIFU. Color Doppler ultrasonography was used to observe if the abdominal aorta was filling and to measure the peak systolic velocity （PSV）, mean velocity （Vm）, average blood flow, resistance index （RI） and pulsatility index （PI） of abdominal aorta before and immedi- ately, 2 h and 6 h after ablation. Pathological changes of the abdominal aorta were also observed. Results The models of liver tumor adjacent to abdominal aorta were successfully established in 40 rabbits. After ablation, blood flow was normal in the abdominal aorta, while no stenosis, collapse nor occlusion was observed. PSV, Vm, average blood flow reduced and RI, PI increased immediately after ablation （all P〈0.05） and recovered to the pre-ablation level （all P〉0.05） 6 h later. Pathological results showed no injury of the abdominal aorta immediately after ablation. Conclusion HIFU ablation of liver tumor adjacent to abdominal aorta can cause transient hemodynamic changes, but has no obvious impact on the aortic wall in rabbit models.