Value Of Multimodal CT In Evaluating Collateral Circulation And Prognosis In Patients With Acute Ischemic Stroke

ObjectiveMultimodal CT(mCTA combined with CTP)was used to evaluate the collateral circulation status,infarct core and ischemic penumbra in patients with acute ischemic stroke(AIS),to explore the value of multimodal CT in the evaluation of collateral circulation and prognosis in AIS patients.Statistics and Methods1.Source: This research originated from the national multi-center study of "Cerebral Collateral Circulation Evaluation and Prediction for Acute Cerebral Ischemia",project number: CSA2016KY001.We enrolled patients according to the study protocol and analyzed the data of our own center.2.Methods: This is a prospective and observational study.We screened AIS patients admitted to our hospital from March 2018 to June 2019,and enrolled patients with symptomatic intracranial artery stenosis according to the inclusion and exclusion criteria.These patients need to complete mCTA as well as CTP examination within 10 days of onset,and the related data of them need to be collected prospectively.(1)The patients were divided into two groups according to the collateral circulation score on mCTA,good collateral circulation group(4~5)and poor collateral circulation group(0~3).The factors influencing collateral circulation were determined by using single factor analysis,and multivariate logistic regression analysis.(2)Compare the difference of CTP parameters in the infarcted core zone(or ischemic penumbra zone)between good collateral circulation group and poor collateral circulation group;Compare the difference of CTP parameters between infarcted core zone and mirrored area,ischemic penumbra zone and mirrored area,infarcted core zone and ischemic penumbra zone.(3)We classified patients into good prognosis group(0~2)and bad prognosis group(3~5)according to the mRS score at 90-day during follow-up,to explore the predictive factors in prognosis by using single factor analysis and multivariate logistic regression analysis.Besides,we established different logistic regression models to predict the prognosis of AIS patients.ResultsWe screened 672 patients with AIS and enrolled 40 eligible patients.However,6 patients were removed because of unqualified image data or loss during follow-up.Finally,the data of 34 patients were analyzed.There were 26 males(76.47%)and 8 females(23.53%),with an average age of 58.85±11.30 years.1.Evaluation of collateral circulation by mCTA in patients with AIS:(1)Of the 34 patients,22 had good collateral circulation(64.71%)and 12 had poor collateral circulation(35.29%);(2)The consistency of evaluation results of collateral circulation between different evaluators was good(K=0.93 between senior imaging doctor and young imaging doctor,K=1.0 between senior imaging doctor and young neurologist,and K=0.93 between young imaging doctor and young neurologist).2.Evaluation of infarcted core zone and ischemic penumbra zone by CTP in patients with AIS: Compared to the mirrored area,CBV as well as CBF of the infarcted core zone decreased apparently(P<0.05);MTT,TTP and Tmax prolonged significantly(P<0.05).In contrast to the mirrored area,CBF of the ischemic penumbra zone got lower,MTT,TTP,and Tmax became longer(P<0.05),there was no obvious difference in CBV between the ischemic penumbra zone and the mirrored area(P>0.05).In comparison with the ischemic penumbra zone,the infarcted core zone had a more significant decrease in CBV and CBF,prolongation in MTT,TTP and Tmax(P<0.05).There was no distinguished difference in rCBV,rCBF,rMTT,rTTP and rTmax when comparing the infarcted core zone(or ischemic penumbra zone)between good collateral circulation group and poor collateral circulation group(P>0.05).3.Analysis of factors influencing collateral circulation:(1)Univariate analysis signified that previous cerebrovascular disease history,low-density lipoprotein,and homocysteine were significantly different between good collateral circulation group and poor collateral circulation group(P<0.05).(2)Multivariate logistic regression analysis manifested that lower low-density lipoprotein and lower homocysteine predicted good collateral circulation.4.The relationship between collateral circulation status assessed by multimodal CT and prognosis of AIS patients: In 34 patients,21 had good prognosis(61.76%)and 13 had poor prognosis(38.23%).(1)Univariate analysis showed that there was significant difference of collateral circulation status,homocysteine,admission mRS score,admission NIHSS score,discharge mRS score,discharge NIHSS score,and infarct volume between good prognosis group and bad prognosis group(P <0.05).(2)Multivariate logistic regression analysis showed that collateral circulation status assessed by multimodal CT was an independent predictor of the prognosis in patients with AIS(P <0.05),a better collateral circulation compensation predict a better clinical prognosis.The regression model which includes collateral circulation,infarcted volume,gender,age and homocysteine has the highest predictive power for prognosis.Conclusions1.The consistency of evaluation results of collateral circulation based on mCTA between different evaluators was good.2.Compared with the mirrored area,parameters of MTT,TTP and Tmax of the infarcted core zone and the ischemic penumbra zone prolonged,CBF decreased;CBV of the infarcted core zone decreased,but CBV of the ischemic penumbra zone did not change significantly.Compared with the poor collateral circulation group,CTP parameters of the infarcted core zone(or ischemic penumbra zone)in the good collateral circulation group did not change significantly.3.Collateral circulation status assessed by multimodal CT is an independent predictor of the prognosis in patients with AIS.The regression model which includes collateral circulation,infarcted volume,gender,age and homocysteine has the highest predictive power for prognosis.