Comparative Study On The Evaluation Of Carotid Atherosclerotic Plaque Instability By SMI And Contrast-enhanced Ultrasound

Objective:to observe the distribution of neovascularization in carotid atherosclerotic plaques with superb microvascular imaging(SMI)and contrast enhanced ultrasound(CEUS),and to investigate whether SMI and CEUS were consistent in detecting the stability of carotid atherosclerotic plaques.Methods:From January 2018 to December 2020,158 cases(a total of 165 plaques)of symptomatic patients with ischemic cerebrovascular disease were selected as t he research object.According to the difference echogenity of the plaques by ultrasound imaging,three groups were divided:low heterogeneity echo group(54 plaques),low homogeneous echo group(58 plaques)and strong heterogeneity echo group(53plaques)patches.The blood flow in the same section plaque were detected with SMI and CEUS,and the results were compared and analyzed.Result:158 cases included 98 males and 60 females,The average age was(74.1+8.2)years old.Among the 54 plaques in the low heterogeneity echo group,37(68.5%)plaques were vulnerable and 17 plaques were stable by SMI,40(74.1%)plaques were vulnerable and 14 plaques were stable by CEUS,and the difference was not statistically significant(P=0.523).Among the 58 plaques in the low homogeneous echo group,43(74.1%)plaques were vulnerable and 15 plaques were stable by SMI,44(75.9%)plaques were vulnerable and 14 plaques were stable by CEUS,and the difference was not statistically significant(P=0.830).Among the 53 plaques in the strong heterogeneity echo group,11(20.8%)plaques were identified as vulnerable type and 42 plaques as stable type by SMI,13(24.5%)plaques as vulnerable type and 40plaques as stable type by CEUS,the difference was not statistically significant(P=0.643).SMI and CEUS showed statistically no significant difference in the detection rate of neovascularization between homogeneous low-echo plaque group and heterogeneous low-echo plaque group(χ~2=0.433,P=0.511;χ~2=0.048,P=0.827).SMI and CEUS showed statistically significant difference in the detection rate of neovascularization between homogeneous low-echo plaque group and heterogeneous high-echo plaque group(χ~2=31.591,P<0.001;χ~2=29.212,P<0.001).SMI and CEUS showed statistically significant difference in the detection rate of neovascularization between heterogeneous low-echo plaque group and heterogeneous high-echo plaque group(χ~2=24.669,P<0.001;χ~2=26.266,P<0.001).Conclusion:SMI and CEUS high consistency in the evaluation results of plaque stability,so SMI can be used as a non-invasive method to detect and evaluate neovascularizationin carotid atherosclerotic plaques.