| Objective:Use 3.0T high resolution magnetic resonance imaging(HR-MRI)technology to image the patients whose middle cerebral artery M1-M2 segment local blood flow signal is lost in MRA and distal imaging is well,which explores the imaging characteristics of the blood vessel wall and Its possible clinical significance.Method:Selected patients who underwent HR-MRI examinations in our hospital from January 2018 to December 2020 in our hospital.The included Patients were MRA middle cerebral artery M1-M2 segments with significant local interruption,HR-MRI showed no occlusion,according to the degree of MCA stenosis Divided into mild stenosis,moderate stenosis,severe stenosis group,observe the imaging characteristics of MCA M1-M2 segment,and explore its Possible clinical significance.Follow the guidelines to give secondary Prevention,carry out long-term follow-up,observe whether the end-Point event of the enrolled Patients occurs,and explore the risk factors for recurrence of ischemic stroke.Result:1.The study enrolled 82 patients who met the inclusion criteria,including 24 cases mild stenosis,33 cases moderate stenosis,24 cases severe stenosis,and 1 vascular variation.Among them,there is a case of small blood vessel empty signal shadow in severe stenosis.Among the three groups,the proportion of male patients with moderate stenosis(78.8%)was higher than that of Patients with mild stenosis(41.7%)and severe stenosis(62.5%),and the difference between the three groups was3 statistically significant(P<0.05)),there was no significant difference in age,history of hypertension,history of diabetes,history of hyperlipidemia,history of hyperhomocysteinemia,smoking,and acute stroke among the three group Ps(P>0.05).2.Among patients with mild MCA stenosis,9 cases(11.1%)were upper wall plaques,9 cases(11.1%)were inferior wall plaques,3 cases(3.6%)were ventral wall plaques,and 3 cases(3.6%)were dorsal wall plaques.Among the patients with moderate stenosis,8 cases(10.1%)had upper wall plaques,13 cases(16.0%)had inferior wall plaques,9cases(11.1%)had ventral wall plaques,and 3 cases(3.6%)had dorsal wall plaques.Among patients with severe stenosis,6 cases(7.4%)of upper wall plaques,8 cases(10.1%)of inferior wall plaques,9 cases(11.1%)of ventral wall plaques,and 1 case(1.2%)of dorsal wall plaques,MCA M1-M2 plaques tended to be distributed in the inferior wall,and the difference between the three groups was not statistically significant.(2=0.502,P>0.05).3.Among patients with mild stenosis,16 cases(19.8%)were unstable plaques,8 cases(10.1%)were stable plaques,and among patients with moderate stenosis,11 cases(13.6%)were unstable plaques and stable plaques There were 22 cases(27.2%)with severe stenosis,2cases(2.4%)with unstable plaques and 22 cases(27.2%)with stable plaques.The difference between the three groups was statistically significant.(P<0.0001)4.With ischemic stroke as the endpoint,Cox proportional hazard regression analysis,there is no statistical difference between age,history of hypertension,history of diabetes,history of hyperlipidemia,history of hyperhomocysteinemia,and smoking Learn meaning.Conclusion:1.Middle cerebral artery stenosis caused by atherosclerotic plaque is the main reason for the disappearance of local blood flow signal in MRA.2.At present,there is no definite basis to support the significant correlation between the interruption of the local blood flow signal of the MRA middle cerebral artery and the recurrence of ischemic stroke. |
