| Purpose:Using magnetic resonance high resolution vessel wall imaging(HR-VWI)technology to analyze and discuss the imaging manifestations and risk factors associated with secondary stroke in patients with spontaneous head and carotid artery dissection(CCAD),looking for specific imaging manifestations associated with stroke,so as to guide clinicians to intervene in patients with head and carotid artery dissection(CCAD)as soon as possible,in order to reduce mortality and disability.The cervicocerebral artery mentioned here refers to the blood vessels of the anterior circulation including the internal carotid artery(intracranial segment and extracranial segment),the anterior cerebral artery,the middle cerebral artery,and the blood vessels of the posterior circulation including the vertebral artery(intracranial segment).and extracranial segment),basilar artery,posterior cerebral artery.Materials and methods:From April 2014 to April 2021,92 patients diagnosed with head and carotid artery dissection(CCAD)in the radiology department of our hospital were selected.These patients underwent routine magnetic resonance scanning and magnetic resonance high-definition vessel wall imaging(HR-VWI)examinations.,the sample included 54 infarct patients and 38 non-infarct patients.The patients were followed up for 3 months,and the end point of follow-up was the occurrence of ischemic stroke caused by the target vessel.From the discovery of the target artery dissection,to the occurrence of stroke in the brain tissue supplied by the target artery.During the follow-up process,the patients were divided into a stroke group and a non-stroke group(control group)according to whether there was a stroke in the brain tissue supplying the distal blood vessels responsible for the follow-up results.Cases in the stroke group included head and carotid artery dissection and corresponding stroke at presentation,and new stroke during 3-month follow-up.The non-stroke group had only head and carotid artery dissection and no stroke during the 3-month follow-up.The two groups were compared in terms of age of onset,gender,onset site(dissection vessel),number of involved vessel segments,degree of stenosis of dissection vessel,presence or absence of intramural hematoma,mural thrombus and dissecting aneurysm,etc.Resolution-Magnetic Resonance,HR-MR)imaging differences.The diseased parts were divided into anterior circulation and posterior circulation vessels,and the probability of arterial dissection and the probability of ischemic stroke caused by arterial dissection were analyzed separately for each vessel.The number of involved segments was mainly analyzed in the internal carotid artery and vertebral artery,because the middle cerebral artery dissection mainly occurred in the M1 and M2 segments,and the posterior cerebral artery dissection mainly occurred in the P1 and P2 segments(possibly due to the limitation of MR spatial resolution).The internal carotid artery is in accordance with the seven-segment method proposed by Bouthillier in 1996,including Cl(cervical segment),C2(rock segment),C3(rupture hole segment),C4(cavernous sinus segment),C5(clinoid segment),C6(eye segment),C7(communication segment),vertebral artery according to the five-segment method,including V1(transverse foramen segment),V2(transverse segment),V3(atlas segment),V4(foramen magnum segment),V5(intracranial segment).An intramural hematoma is defined as a long or fusiform hyperintensity shadow between the intima and adventitia(acute phase),a mural thrombus is defined as a subintimal thrombus in the false lumen due to low flow or turbulent flow,A dissecting aneurysm is defined as a localized bulge of the vessel wall,forming a round,tumor-like structure.The degree of vascular stenosis was measured as the transverse diameter of the blood vessel at the narrowest part of the true lumen,and the numerical ratio was the ratio of the smallest transverse diameter at the stenosis to the average value of the upper and lower normal blood vessel diameters × 100%.The data were analyzed and processed with SPSS 24.0 statistical software.Age,gender,degree of stenosis of dissection vessel,presence or absence of mural thrombus,intramural hematoma,dissecting aneurysm,number of segments involved in stroke,location of disease and outcome were statistically described.In the univariate analysis,the chi-square test was used to test the difference in the number of involved segments between the two groups,and the pearson chi-square test was used to analyze the gender,mural thrombus,intermural hematoma,and dissection in the stroke group and the non-stroke group one by one.Correlation of aneurysm occurrence.Differences in the degree of stenosis between the stroke group and the control group were analyzed using the Wilcoxon signed-rank test.The variables related to the occurrence of stroke were screened out by the above univariate analysis method,and then the selected variables were used as independent variables,and the occurrence of stroke was used as the dependent variable to establish a binary logistic regression analysis model,and SPSS 24.0 was used for analysis.When the P value was less than 0.05,as a basis for statistical significance,regression analysis was used to screen out independent risk factors for stroke.Result:The overall sample size was 92 cases,including 63 males and 29 females,aged 17 to 74 years old,with an average age of(47.3±13.2)years old.Among them,54 patients had infarction and 38 were non-infarct patients.The overall infarction rate was 58.7%.Among them,the infarction rate caused by middle cerebral artery dissection was the highest,reaching 70%(21/30),followed by basilar artery 58.3%(7/12),unilateral internal carotid artery 55.5%(20/36),and unilateral vertebral artery 46.2%(12/26),unilateral posterior cerebral artery 33.3%(2/6).In univariate analysis,it was found that the stroke group was significantly different from the non-stroke group in terms of disease site,number of involved vascular segments,degree of stenosis,presence of intramural hematoma,mural thrombus,and dissecting aneurysm(P<0.05).;Through binary logistic regression analysis,it was found that severe vascular stenosis(stenosis degree≥75%),number of involved segments(internal carotid artery more than 3.6,vertebral artery more than 2.8),presence of intramural hematoma,and mural thrombus were independent of stroke.risk factors.Age(P=0.087>0.05)and the presence of dissecting aneurysm(P=0.181>0.05)were associated with the occurrence of stroke,but were not independent risk factors for stroke.Through the above statistical analysis,we found that in the daily diagnosis of head and carotid artery dissection,when severe vascular stenosis(stenosis degree≥75%),intramural hematoma,mural thrombus,the number of involved segments(internal carotid artery more than 3.6,when the vertebral artery exceeds 2.8)these factors,it indicates that the probability of recent stroke in these cases is significantly increased,and early intervention can be given appropriately,thereby reducing the incidence and mortality of stroke.Conclusion:In patients with head and carotid artery dissection,those with intramural hematoma,mural thrombus,severe stenosis of dissection vessels(stenosis degree≥75%),more than 3.6 involved segments of internal carotid artery dissection,and more than 2.8 involved segments of vertebral artery dissection are more likely to occur.Ischemic stroke is an independent risk factor for stroke. |
PDF Full Text Request