The Imaging Studies Of Spontaneous Recanalization Of Infarct Of Internal Carotid Artery System

Objective: To investigate imaging characteristic for acute stroke patients without responsible artery stenosis or occlusion through the use of MRI diffusion-weighted imaging(DWI),MR angiography(MRA),CT angiography(CTA)imaging method,analysis of internal carotid artery system of early cerebral infarction vascular recanalization rate of spontaneous recanalization,recanalization time,corresponding to the responsible vessels infarction patterns,explore the major contributing stroke mechanism of spontaneous recanalization,so as to help clinical adjusting early intervention of patients with cerebral infarction and prevention of relapse of cerebral infarction with atherosclerotic stenosis of internal carotid artery system.Methods: We retrospectively collect 441 patients who were diagnosed as acute cerebral infarction,treatment of DWI sequence and visible cerebral infarction,infarction in internal carotid artery blood supply area in General Hospital Affiliated to Tianjin Medical University from May 2015-2016 year.According to the 3D-TOF sequence showed whether vascular stenosis or not of infarction patients.441 patients were divided into two groups: recanalization group(infarction without stenosis of responsibility vascular)in 141 cases,stenosis Group(infarction with responsibility vascular stenosis)in 300 cases.Statistics between the two groups in gender,age,time from onset to the MRA examination,and infarction side patterns and so on.Results: 141(31.97%,male,87 female,54)cases of cerebral infarction patients without responsibility vascular stenosis through MRA,300(68.03% male,192 female,108)cases of cerebral infarction were visibled responsibility vascular stenosis or occlusion through MRA.The average time from onset of stroke were 1.79 +1.34,2.16 + 1.75 days through MRA between non Stenosis group and stenosis group.In 3 days,non stenosis patients ro stroke patients ratio is about 30%,In 3-7 days the ratio gradually decreased to 10%.single infarct is the most common pattern in all patients between both two groups,the PAI pattern(recanalization group 60.28%,stenosis group 32%)is the most common,followed by PI pattern(reperfusion group were 24.11%,stenosis group30%),and BZI pattern(recanalization group 7.80%,stenosis group 16.33%);in mixed mode,PI+PAI(reperfusion group 5.67%,stenosis group 12%)is common to see in both groups,Concomitant with PI+BZI(reperfusion group were 2.13%,stenosis group4.67%),PAI+BZI(reperfusion group were0%,stenosis group 2.67%),and PI+PAI+BZI(recanalization group 0%,stenosis group 2.33%).Compare the volume of infarct in two groups,in the level of smaller than 5%TVB(total volume brain)(reperfusion group were139(98.58%),stenosis group 262(65.5%)),in the level of 5%-10%(recanalization group2(1.42%),stenosis group20(5%)),in the level of lager than 10%(recanalization group 0%,stenosis group18(4.5%)).Conclusion: The non stenosis of responsibility infarct vascular can be used to predict spontaneous recanalization(SR).The mean incidence of early spontaneous racanalizaton(SR)is 31.97% of infarction,the average time of spontaneous recanalization from onset of infarction to MRA was 1.79 ± 1.34 days.In the early stage of cerebral infarction(less than 3 days),with time prolonging,the incidence of non-stenosis showed a increase tendency gradually,after 3 days,it declined for early thrombosis is mainly composed of fresh thrombus which is dissolved easily to recanalization;within 3 days,ruptured plaque can produce emboli with distant metastasis.The most common pattern is single infarction more than multiple in both.The farther the Blocking site,the smaller the thrombus volume,the higher the recanalization,the rate of recanalization of main atery is lower than distal branch.The infarct volume in the SR group are mainly in the level of smaller than 5%which significant small than stenosis group,we hypothesis that the smaller the infarct volume,the higher the rate of the SR.