Correlation Study Of CT Cerebral Perfusion Imaging Potential Recuperation Ratio On Prognosis After Mechanical Thrombectomy After More Than 6 Hours Of Acute Ischemic Stroke

Objective:This paper aims to investigate the correlation between the potential recuperation ratio（PRR）of ischemic tissue in CT perfusion imaging and the occurrence of bleeding conversion after mechanical thrombectomy and the prognosis at 90 days post-operation in patients with acute anterior circulation large occlusion ischemic stroke with a time window of over 6 hours.Methods:In this study,patients diagnosed with anterior circulation great vessel occlusion and receiving mechanical thrombectomy in a certain hospital from January2018 to June 2022 were retrospectively collected,and a total of 157 cases were collected according to the constriction standard strictly.There were 86 males（54.8%）and 71 females（45.2%）,ranging in age from 32 to 93 years old.Clinical baseline data of all enrolled patients were collected（gender,age,hypertension,diabetes,coronary heart disease,smoking and drinking history,atrial fibrillation,previous anticoagulation therapy,NIHSS score on admission,receiving intravenous thrombomysis,m TICI3grading,postoperative hemorrhage transformation,and m RS Score 90 days after surgery）.Relevant biochemical indicators（HDL,LDL,triglyceride,total cholesterol,homocysteine）;Parameters related to CT perfusion imaging:ASPECT score,core infarct volume(V_CBF<30%),low perfusion area volume(V_Tmax>6sand V_Tmax>10s)and penumbra(V_Tmax>6s-V_CBF<30%).The recovery ratio and hypoperfusion intensity ratio（HIR）of ischemic tissue were calculated.According to m RS Scores 90 days after surgery,patients were divided into good outcome group（≤2 points）and poor outcome group（>2 points）.According to the head CT results of postoperative review,the patients were divided into bleeding conversion group and non-bleeding group.SPSS26.0 software was used for statistical analysis.General clinical data and CT perfusion imaging parameters were compared by univariate analysis.Multivariate Logistic regression analysis was used to screen CT perfusion imaging parameters that affected the occurrence of hemorrhage transformation and short-term outcome after thrombectomy.Further,the ROC curve was used to analyze the predictive value of preoperative CT perfusion imaging parameter PRR on the occurrence of hemorrhage transformation after thrombolectomy and 90-day short-term adverse outcome.P<0.05was considered statistically significant.Results:1.A total of 58 patients（36.9%）had good outcomes 90 days after thrombectomy（m RS 0-2）.The clinical data,biochemical indexes and CT perfusion imaging parameters of patients in the good outcome group and the poor outcome group were analyzed by single factor,and the results were as follows:decompressive craniotomy,bleeding transformation,penumbra region,PRR and V_CBF<30%,the difference was statistically significant（P<0.05）.The above indexes were included in multivariate logistic regression analysis,and the results were as follows:PRR（OR=0.077,95%CI:0.010-0.622,P=0.016）and V_CBF<30%（OR=0.1.047,95%CI:1.024-1.071,P<0.001）.Further ROC curve analysis:PRR and V_CBF<30%the areas under the curve were 0.857 and 0.846,respectively.PRR had high predictive efficacy on the outcome at 90 days after thrombectomy.2.A total of 66 patients（42.0%）experienced hemorrhage transformation after thrombectomy.The baseline data,biochemical indexes and CT perfusion imaging parameters of patients in the hemorrhage transformation group and the non-hemorrhage transformation group were analyzed as follows:systolic blood pressure,diastolic blood pressure,bone flap decompression,grade m TICI3,V_CBF<30%,PRR and penumbra volume,the difference was statistically significant（P<0.05）.The above indexes were included in multivariate logistic regression analysis,and the results were as follows:m TICI3（OR=2.404,95%CI:1.069-5.404,P=0.034）and PRR（OR=0.014,95%CI:0.001-0.323,P=0.008）.Further ROC curve analysis:the areas under the curve of grade m TICI3 and PRR were 0.603 and 0.784,respectively,indicating that PRR had higher predictive efficacy for bleeding transformation after thrombectomy.Conclusion:1.CT perfusion imaging parameters PRR and V_CBF<30%of them have clinical value,which can be used to determine the prognosis of patients with acute anterior circulation large vessel occlusion more than 6 hours after onset in a short time,so as to screen out more suitable patients with mechanical thrombectomy through super window.2.PRR parameters have a reliable predictive effect on postoperative hemorrhage conversion and 90-day postoperative outcome after MT:the higher the PRR parameters are,the lower the postoperative hemorrhage conversion rate and the higher the 90-day postoperative good prognosis.