Objective To observe area of coagulation necrosis after microwave ablation(MWA)of rabbit liver showed on contrast-enhanced ultrasound(CEUS)in comparison with pathological findings.Methods Twenty-five healthy male experimental rabbits were equally randomly divided into L0,M0,H0,M7 and M14 groups.MWA was achieved with different power and time,and then CEUS and pathological examinations were performed,respectively.Four target areas of rabbit liver were ablated under 20 W for 1 min in L0 group,under 30 W for 1 min in M0 group and under 30 W for 3 min in H0 group,and the ablated areas were observed on the same day after MWA,while 2 target areas of rabbit liver were ablated under 30 W for 1 min in M7 and M14 groups,and the ablated areas were observed 7 days and 14 days after MWA,respectively.The ablated foci and ablated foci+edema band(inflammatory reaction band,IRB)showed on CEUS and pathology were compared,and their differences and changes with time going were analyzed.Results On the day of ablation,the extent of ablation foci,ablation foci+IRB as well as IRB in L0,M0 and H0 groups showed on CEUS were all larger than pathological findings under light microscopy(all P＜0.05),and the difference value of the length of the ablation foci between 2 methods increased sequentially among group L0,M0 and H0(all adjusted P＜0.05).Seven days after ablation,the area of ablation foci measured with CEUS in M 7 group was slightly larger than that measured with pathology(adjusted P=0.045),but no significant difference of the length nor the short diameter was found(both adjusted P＞0.05).Fourteen days after ablation,no significant difference of the length,the short diameter nor the area of ablation foci was detected between 2 methods in M14 group(all adjusted P＞0.05).The length,short diameter and area of ablation foci in M0 group measured with CEUS or pathology were all smaller than those in M 7 and M14 groups(all adjusted P＜0.05),while no significant difference was found between the latter 2 groups(all adjusted P＞0.05).Conclusion On the day of MWA of rabbit liver with different power and time settings,the areas of ablation foci,ablation foci+IRB and IRB showed on CEUS were larger than pathological findings.The range of ablation foci showed on CEUS 7 days after ablation was basically in line with pathology,indicating that CUES should be reexamined 7 days after ablation to evaluate the actual extent of coagulation and necrosis of ablation foci.