A Preliminary Study On The Correlation Between Microembolus Signal And Ischemic Stroke In Patients With Middle Cerebral Artery Stenosis

Objective:Transcranial Dopplersonography(TCD)was used to investigate Microembolic signals(MES)in patients with Middle cerebral artery(MCA)stenosis.To investigate the correlation between microemboli signal and middle cerebral artery stenosis and ischemic stroke,and to provide clinical data for the occurrence and development of ischemic cerebrovascular disease.Methods:First of all,will be included in the standard of the research object is divided into middle cerebral artery stenosis was confirmed by head mri examination of acute cerebral infarction group and middle cerebral artery stenosis without cerebral infarction group,then,by transcranial doppler ultrasound to monitor the object of study of middle cerebral artery blood flow,records of middle cerebral artery in micro embolus signal appears,if micro embolus signal is detected,Determine whether it is in the same direction as the blood flow.The basic information of the subjects,whether there are risk factors related to cerebrovascular development and the stenosis degree of middle cerebral artery were recorded,and the location and size of cerebral infarction were evaluated by head MRI.Finally,the two groups were compared.Results:1.There were no significant differences in age(63.28±7.28 in positive group and 60.94±6.50 in negative group),gender,blood lipid index and smoking history between the two groups(P>0.05).However,this study showed that MES positive rate was higher in patients with hypertension and diabetes,and the difference between the two comparison groups was statistically significant(P<0.05).49 cases of acute cerebral infarction with middle cerebral artery stenosis were compared with 70 cases of patients without cerebral infarction with middle cerebral artery stenosis.The positive rate of cerebral infarction group and non-cerebral infarction group was 30.6%vs11.4%,respectively.The positive rate of microemboli in the two groups was statistically significant(X~2=6.803,P=0.009).2.According to different degrees of middle cerebral artery stenosis,119subjects were divided into mild,moderate and severe stenosis groups.The positive detection rates of microemboli in the three groups were 8.62%vs24.0%v S54.5%,and pairwise comparison was made on the positive detection rates of microemboli in the three groups.The results showed that the positive rate of microemboli among the three groups was statistically significant(X~2=13.715,P=0.001).Bonferroni method was used to correct the test standard A of 0.05/3=0.017 for comparison between the three groups.The positive rate of mild stenosis was significantly lower than that of moderate stenosis(X~2=4.789,P=0.029),and the positive rate of moderate stenosis was significantly lower than that of severe stenosis(X~2=4.044,P=0.044).The positive detection rate of mild stenosis was significantly lower than that of severe stenosis(X~2=14.553,P<0.001),and Logistic regression analysis was performed(independent variable was the degree of stenosis,the dependent variable was MES).The results showed that the positive rate of MES was different with different stenosis degree(P<0.001).With mild stenosis as the control group,Exp(B)risk increased gradually compared with moderate and mild stenosis and severe and mild stenosis.The results showed that with the increase of middle cerebral artery stenosis,the positive detection rate of MES would also increase.3.According to the size of infarction area,patients with middle cerebral artery stenosis diagnosed by imaging were divided into groups,and the positive rate of MES was compared between different groups.The results showed that the positive rate of MES was significantly higher in large cerebral infarction group than in small cerebral infarction group(24.4%vs62.5%,P=0.032).There were significant differences between the two groups,indicating that MES was more easily detected in the group with large cerebral infarction.4.According to NIHSS score,49 patients with cerebral infarction were divided into NIHSS score<5 and NIHSS score≥5.The positive rate of microemboli was 23.1%vs60.0%,respectively,and there was a significant difference in the positive rate of MES between the two groups(X~2=5.108,P=0.024).The results indicated that the positive rate of microemboli was correlated with NIHSS score,but the influence of race,region and other related factors could not be excluded,and there were errors due to the small sample size.Conclusions:1.The positive rate of microemboli was correlated with the degree of middle cerebral artery stenosis,and the positive rate of microemboli increased with the severity of stenosis.2.The positive rate of microemboli was positively correlated with the occurrence of ischemic stroke,and the larger the cerebral infarction area was,the higher the positive rate of microemboli was.