Experimental Study On The Effect Of CEUS Combined With ARFI In Microwave Ablation For Hepatic Alveolar Echincoccosis In Rats

Objective: To evaluate the value of CEUS combined with ARFI technique in the evaluation of microwave ablation of HAE lesions in rats.Methods: 45 HAE rat models were randomly divided into experimental group(n﹦35)and control group(n﹦10).Microwave ablation was performed under ultrasound guidance in the experimental group,but not in the control group.The maximum diameter of the lesion was measured by routine ultrasound,CEUS and ARFI before and after 1 month of ablation.The mean gray scale ratio and shear wave velocity were measured after 1 month of ablation and control group.Then all the rats were killed,and staining for CD34 and Masson was performed on the pathological sections.The MVD and fibrosis area of the corresponding marginal zone were calculated respectively for correlation analysis.The total inactivation and residue of the lesion were judged according to the pathological results,and the diagnostic efficacy was compared.Results: Experimental group with 28 rats(30 lesions)and control group with 10 rats(10 lesions)were selected in the study.There were 19 complete ablations(21 lesions)and 9 residual lesions(9 lesions).(1)The gray scale ratio of edge zone in three groups was positively correlated with MVD(r=0.541,r=0.831,r=0.639,all P<0.05),SWV value was positively correlated with fibrosis area(r=0.494,r=0.778,r=0.693,all P<0.05).After 1 month of ablation,the mean marginal gray scale ratio and MVD of the complete ablation group were significantly lower than those of the residual group and the control group,while the mean SWV value and fibrosis area were higher(P <0.001).There was no difference between the residual group and the control group(P >0.05).(2)The maximum diameter of the lesions measured under CEUS and ARFI imaging was larger than that of conventional ultrasound(P <0.05),but there was no significant difference between CEUS and ARFI(P <0.05).The maximum diameter of ablation focus were smaller than before in the experimental group(all P <0.001).(3)The accuracy of diagnosis of residual HAE lesions under CEUS after ablation was 83.33%,the sensitivity was 88.89%,the specificity was80.95%,consistent with pathological findings(Kappa=0.638).The accuracy of ARFI diagnosis HAE lesion residue was 86.67%,the sensitivity was 66.67%,the specificity was 95.24%,consistent with pathological findings(Kappa=0.661).The accuracy of the combination was 93.33%,the sensitivity is 100%,the specificity was 90.48%,consistent with pathological findings(Kappa=0.851).Conclusions: CEUS and ARFI imaging techniques can determine the ablation range and biological status of marginal zone of rat HAE models in a real time,non-invasive and comprehensive manner.The combination of CEUS and ARFI technology has good application value in evaluating the effect of microwave ablation of HAE lesions.