HRMRI Evaluation Of Carotid Plaque And Correlation Study With IS Based On 3D-ASL

Objective:Use 3.OT high-resolution nagnetic resonance imaging to evaluate the composition,load and type of carotid atherosclerotic plaque;analyze the risk factors affecting the formation of vulnerable plaques;explore the relationship between caroaid plaque stability,cerebral blood flow perfusion and ischemic stroke;compare the diagnostic effect of carotid ultrasound and magnetiu resonance imaging on carotid vulnerable plaque;analysis sensitivity and specificity of magnetic resonance imaging in diagnosis of vulnerable carotid plaque.Methods:① Select 84 patients with carotid plaque high-resoluaion magnetic resonance imaging in our hospital from July 2018 to October 2019,use histological analysis of carotid plaques to assess plaque type(American Heart.Association classification,Ⅳ-Ⅴ and Ⅵ types are defined vulnerable plaques.The study subjects were divided into vulnerable plaque group(36 cases)and stable plaque group(48 cases).Compare the general data of the two groups and the difference of carotid plaque distribution.General information includes gender,age,hypertension,hyperlipidemia,corolary heart disease,smoking,body mass index,diabetes and history of ischemic stroke;②The patients are divided into symptomatic and non-symptomatic groups according to whether the cerebral hemisphere of the carotid blood supply area had ischemic stroke.In this study,a total of 168 carotid artery iuages were obtained,including 80 in the symptomat.ic group and 88 in the non-symptomatic group.Compare the differences in carotid atheroscleror1c plaque composition,load,and CBF value between the two groups.Plaque componenl refers to plaque bleeding(IPH),lipid necrosis core(LRNC),ruptured fiber cap(FCR),calcification(CA),and plaque load refers to the maximum wall thickness(maxWT),the normalized wall index(NWI),lumen area(LA);③Comparative analysis of ultrasound imaging and magnetic resonance imaging of vulnerable plaque,stenosis and plaque thicknes;④The results of high-resolution magnetic resonance imaging of carotid plaque in 15 patients confirmed by surgery were compared with pathological typing.Results:①Patients in the vulnerable plaque group are higher in age and body mass index than the stable plaque group,and there are more people with history of hypertension and diabetes than the stable plaque group,the difference is statistically significant(P<0.05);There is no significant difference in the location distribution of carotid plaque between the two groups(P>0.05),and the beginning of the internal carotid artery is the most common.③The incidence of LRNC and IPH in the non-symptomatic group is significantly lower than that in the symptomatic group(P<0.05);there is no significant difference in the incidence of CA and FCR between the two groups(P>0.05).The volume of CA and LRNC,maxWT,NWI in the symptomatic group is significantly larger than that in the non-symptomatic group(P<0.05),there is no significant difference in LA between the two groups(P>0.05).The CBF value of the internal carotid artery blood supply area of the symptomatic group is significantly lower than the non-symptomatic group,and the difference is statistically significant(P<0.05).④The number of vulnerable plaques detected by ultrasound Doppler(62 cases)is significantly less than the number of HRMRI(86 cases),and the difference between the two groups is statistically significant(P<0.05).HRMRI and ultrasound examination show no significant.difference in the degree of stenosis and plaque thickness(P>0.05).⑤The sensitivity of high-resolution magnetic resonance imaging for diagnosis of type Ⅲ,Ⅳ-Ⅴ,Ⅵ and Ⅶ carotid plaques is 0.800,1.000,0.857,1.000,and the specificity is 1.000,0.929,1.000,0.941.There is no significant difference in the detection rate of plaque between magnetic resonance imaging and pathology.Conclusion:In terms of age,body mass index,hypertension,and history of diabetes,the vulnerable plaque group is higher than the stable plaque group;The occurrence of ischemic stroke is related to the LCR,IPH,NWI and maxWT of ipsilateral carotid plaque,and ischemic stroke is closely related to the decrease of cerebral blood perfusion.It is feasible to predict the occurrence of ischemic stroke through the composition and load of carotid plaque and CBF value;Magnetic resonance is significantly higher in the detection rate of carotid vulnerable plaque than ultrasound Doppler;Application of HRMRI can show the component signal characteristics of plaque,and compare with the pathological results which has good accuracy in diagnosing different types of carotid plaque.HRMRI examination assess the stability of plaque can provide a reliable imaging basis for the prevention of stroke,which is conducive to timely clinical treatment.