Relationship Between Intracranial Artery And Infarct Size By High Resolution Magnetic Resonance Imaging

Study on the Relationship between Middle Cerebral Artery Plaque and Infarct Type by High-resolution Magnetic Resonance ImagingObjectives:This study focused on the use of high-resolution magnetic resonance imaging(HRMRI)to analyze the relationship between the stenosis of the middle cerebral artery(MCA)atherosclerosis and the type of infarction distribution.And further explore the different types of cerebral infarction and plaque nature,remodeling rate and the possible mechanism of stroke in patients.Methods:We retrospectively analyzed the clinical data of patients with MCA blood supplied ischemic stroke and high-resolution magnetic resonance imaging within 14 days of treatment from Nanjing Drum Tower Hospital in 2012-2016.Perforating artery infarct(PAI),pial infarct(PI),border zone infarct(BZI)were performed on diffusion weighted imaging(DWI)and mixed infarcts(PAI+PI,PAI+BZI,PI+ BZI,PAI+PI+BZI)were also presented.The stenosis rate and remodeling rate of MCA M1 were measured on sagittal HRMRI,and the morphological indexes such as position,length and thickness were collected.The reconstruction rate of positive remodeling(PR)is more than 1.05 and negative remodeling(NR)is low than 0.95.Patients with PAI,PI±and BZI were divided into single type infarct group.Patients with PAI+PI,PAI+BZI,PI+BZ,PAI+PI+BZI were assigned to mixed type infarct group.Results:A total of 52 patients with MCA stenosis ≤50%were included in the study.32 cases were single type infarct group and 19 cases were mixed type infarct group among them.There were 22 cases of patients with PAI(68.8%),6 patients with PI(18.7%)and 4 with BZI(12.5%),22 patients with PR(68.8%)in single.In the mixed type infarct group,7 were PAI+BZI(36.8%),2 were PAI+PI(10.6%),5 were PI+BZI(26.3%)and 5 were PAI+PI+BZI(26.3%)±17 were PR(89.5%).The degree of stenosis in the mixed type infarct group was more severe(P=0.01)and the plaque thickness was larger(P=0.001)than single type infarct group.Conclusions:Different degrees of middle cerebral artery stenosis,the distribution of infarction is different.In single type infarct group,the cerebral infarction pattern is mainly PAI,while PAI+BZI is most common in mixed.At the same time,HRMRI found that increased stenosis and plaque thickness may be associated with mixed infarction for patients with mild MCA stenosis.Study on the pathogenesis of perforating arterial infarct by stroke morphologyBackground and Purpose:Although computed tomographic angiography(CTA)is more widely available,quicker and offers excellent information about the degree of stenosis less affected by hemodynamic effects,it has several limitations.Our purpose was to explore the value of high-resolution magnetic resonance head-neck integrated vascular wall imaging to the Chinese Ischemic Stroke Subclassification(CISS)in patients with stroke.The relationship between stroke morphology and PAD was analyzed by observing the size of patients with PAD in DWI.Method:This was a retrospective study included fifty-nine patients with ischemic stroke,who underwent CTA and HRMRI.We compared the effects of two methods on CISS.We measured the shaft length of perforating artery infarct direction of infarction and length of maximum cross-sectional infarction,and did semi-automated calculation of infarct volume for PAD in CTA(non-PAD group)and HRMRI(PAD group)examination,respectively.The longitudinal and transverse ratios of infarcts in patients with PAD were analyzed by ROC curveResults:Using CTA,there were 26 cases(44.0%)of ICAS,7 cases(11.9%)of ECAS,19 cases(32.2%)of PAD,7 cases of UE(11.9%),none of OE,however,through HRMRI examination,it was divided into 44 cases(74.6%)of ICAS,5 cases(8.5%)of ECAS and 8 cases(13.6%)of PAD,none of UE and 2 cases(3.3%)of OE.This was statistical difference between the two methods on CISS(p<0.01).The results of non-PAD group were compared with PAD group,we found that Infarct volume was larger(P<0.05).The length of the direction axis was also different(P<0.05),and this had a discrepancy in the length ratio of the two layers(P<0.05).The receiver operating characteristic(ROC)analysis indicated that a longitudinal and transverse ratios of infarcts cut-off of 1.575(area under the ROC curve[AUC],0.952;P=0.001).Conclusion:HRMRI has a role of dual imaging of the lumen and vessel wall,which is superior to CTA for CISS.In the absence of HRMRI,we can combine volume,shape of infarction,the shaft length of perforating artery infarct direction,length of the maximum cross-sectional infarction and ratio of them in the DWI image to separate ICAS from PAD.