Using SMI And CEUS To Evaluate The Neovascular In Different Thinkness Carotid Atherosclerotic Plaque

Objective: To research the neovascular in the carotid atherosclerotic plaques using superb microvascular imaging(SMI)and contrast enhanced ultrasound(CEUS),and to compare the difference of the neovascular in different thinkness carotid atherosclerotic plaques.Also to make a comparison with superb microvascular imaging(SMI)and contrast-enhanced ultrasound(CEUS)on checking the neovascular in the carotid atherosclerotic plaques.Methods:Selected 56 patients(40 males and 16 females,aged 41~84 years old,average 64.1±8.2 years old)with 80 hypoechoic and/or isoechoic carotid atherosclerotic plaques these were diagnosed by conventional two-dimensional ultrasound and doppler flow ultrasound during July 2014 to December 2015.There was no statistically significant difference in gender and age.And all included patients signed informed consent before contrast-enhanced ultrasound(CEUS).According to the thickness of plaque,plaques were into three groups: plaque thickness 1.5mm~2.4mm,24 cases;plaque thickness 2.5mm~2.4mm,28 cases;plaque thickness≥3.5mm,28 cases.Firstly,we used conventional ultrasound to observe the location,echo,size,shape of carotid atherosclerotic plaques and to measure the thickest section of carotid atherosclerotic plaques for all included patients.In this section,we researched the enhancement of plaque by using SMI.As well,we researched the enhancement of plaque by using CEUS in this thickest section.Observed and recorded the enhancement of plaques with SMI and CEUS.On the base of enhancement classification criteria,to grade and count all date.We used SPSS17.0 statistical software to apply spearman-test for the result of the enhancement by SMI and CEUS respectively.Rank correlation coefficient of spearman rs>0 shows positive correlation,rs<0 shows negative correlation,rs=0 shows zero correlation(rs is the estimated value of the totality rank correlation coefficient--ρs).And then we used Kappa test to check the consistency between SMI and CEUS on examining the neovascular in the carotid atherosclerotic plaques.Kappa>0 shows there is statistics significance,the higher Kappa shows the better consistency;Kappa≥0.75 shows satisfactory consistency,but Kappa < 0.4 shows consistency unsatisfactory;Kappa=+1 shows two results reached a consensus;Kappa=-1 shows two results inconsistent absolutely;Kappa=0 shows two results are due to chance;Kappa<0 shows two results are meaningless.Results:1 SMI test showed: plaque thickness 1.5mm~2.4mm group,10 cases(41.7%)of 0 level enhancement,9 cases(37.5%)of 1 level enhancement,4 cases(16.6%)of 2 level enhancement,1 case(4.2%)of 3 level enhancement;plaque thickness 2.5mm~3.4mm group,1 case(3.6%)of 0 level enhancement,2 cases(7.1%)of 1 level enhancement,9 cases(32.1%)of 2 level enhancement,16 cases(57.2%)of 3 level enhancement;plaque thickness ≥3.5mm group,0 case(0.0%)of 0 level enhancement,3 cases(10.7%)of 1 level enhancement,11 cases(39.3%)of 2 level enhancement,14 cases(50.0%)of 3 level enhancement.2 CEUS test showed: plaque thickness 1.5mm~2.4mm group,12 cases(50.0%)of 0 level enhancement,7 cases(29.2%)of 1 level enhancement,3 cases(12.5%)of 2 level enhancement,2 cases(8.3%)of 3 level enhancement;plaque thickness 2.5mm~3.4mm group,2 cases(7.1%)of 0 level enhancement,1 case(3.6%)of 1 level enhancement,8 cases(28.6%)of 2 level enhancement,17 cases(60.7%)of 3 level enhancement;plaque thickness ≥3.5mm group,0 case(0.0%)of 0 level enhancement,4 cases(14.3%)of 1 level enhancement,13 cases(46.4%)of 2 level enhancement,11 cases(39.3%)of 3 level enhancement.3 SMI enhancement result and CEUS enhancement result with spearman-test showed: the rank correlation coefficient of spearman rs(SMI)=0.539 > 0.000,rs(CEUS)=0.457 > 0.000,meaning that SMI and CEUS all showed the enhancement of different thickness plaque is proportional to the thickness of plaque.4 In addition,SMI compared with CEUS,Kappa=0.755>0.75,showed SMI and CEUS have quite satisfactory consistency on examining the neovascular in the carotid atherosclerotic plaques.Conclusion:1 There was significant difference in the density of neovascular in different thickness hypoechoic and/or isoechoic carotid atherosclerotic plaques.That is to say,the density of neovascular in different thickness hypoechoic and/or isoechoic atherosclerotic plaque is proportional to the thickness of plaque.2 SMI and CEUS all can diagnose neovascular in carotid atherosclerotic plaque.So SMI can be used as a new ultrasonic technique in the diagnosis of neovascular in carotid atherosclerotic plaque.