A Preliminary Study Of Imaging Features After Endovascular Treatment Of Acute Anterior Circulation Large Vessel Occlusion Stroke

Part Ⅰ:Prolongation of Intraparenchymal Contrast Enhancement after Stent-Retriever MechanicalThrombectomy in Acute Ischemic Stroke:Results from the ACTUAL RegistryObjective:Intraparenchymal contrast enhancement,detected in post-procedural non-enhanced CT,is a common phenomenon in acute stroke patients given mechanical thrombectomy.Contrast enhancement within the first 24 h post-mechanical thrombectomy is considered to have no negative effect on prognosis;however,the relationship between prolongation of contrast enhancement over the first post-procedural 24 h and prognosis has not yet been reported.Therefore,in this study,we aimed to investigate the relationship between prolongation of intraparenchymal contrast enhancement and clinical outcome after stent-retriever thrombectomy in acute anterior circulation occlusion.Methods:The analyses used data from the Treatment for Acute Anterior Circulation Ischemic Stroke Registry(ACTUAL),a multicenter,retrospective,registered program of intra-arterial therapy in patients with acute anterior circulation stroke caused by proximal intracranial arterial occlusions at 21 stroke centers in China.We enrolled all patients who underwent initial(first 24-48 h)and secondary(48-72 h)non-contrast computed tomography following stent-retriever thrombectomy.The characteristics of patients with and without prolongation of intraparenchymal contrast enhancement were compared.Binary logistic regression analysis was used to identify the correlation between prolongation of contrast enhancement and 90-day clinical outcomes.Results:A total of 632 patients underwent mechanical thrombectomy with retrievable stents.The first follow-up head NECT after surgery revealed a high incidence of intraparenchyal hyperdensities of 56.8%(359/632).After a second follow-up of the head NECT.The incidence of prolongation of contrast enhancement in patients with intraparenchymal hyperdensities was 46/359(15.6%).The final analysis of 46patients with prolonged contrast agent enhancement was compared with 273 patients without prolonged contrast agent enhancement.Despite in the preliminary analysis,we found that patients with prolonged contrast enhancement had a higher neutrophil ratio(median 0.86 vs 0.81;P = 0,002)and a higher international standard ratio(median 1.11 vs 1.03;P = 0.017).We also found that patients without prolongation of contrast enhancement had better 90-day clinical outcomes(P = 0.029).However,in the binary logistic regression analysis,we found that prolongation of contrast enhancement after mechanical thrombectomy was not associated with 90-day clinical outcomes,whereas higher neutrophil ratio(>0.83)was the only predictor of 90-day poor functional outcome.Conclusions:Our findings suggest that prolongation of contrast enhancement on post-procedural follow-up non-enhanced CT,resolving within 72 h,had no negative effect on 90-day functional outcomes.Part Ⅱ:Outcome in patients with "successful" reperfusion in acute anterior circulation stroke treated with mechanical thrombectomy:TICI 3 versus TICI 2bObjective:To investigate the prognosis discrepancy between patients with acute anterior intracranial circulation ischemic stroke who underwent mechanical thrombectomy and resulted in reperfusion Thrombolysis in Cerebral Infarction scale(TICI)level 2b and 3.Methods:Patients with acute anterior circulation of large vascular occlusion and the implementation of mechanical thrombectomy in department of neurology in Jinling Hospital of Nanjing University school of medicine and Zhongshan affiliated Xiamen University Hospital within 6 hours of onset between January 2015 to November 2016 were retrospective selected,retrospectively.Patients with reperfusion stage TICI 2b to TICI 3 after endovascular procedural were finally enrolled and divided into TICI 2b and TICI group.The 3-month modified Rankin Scale(mRS)were compared between the two groups.Results:A total of 83 patients were enrolled in this study,including 38 patients with TICI grade 2b and 45 patients with TICI grade 3.The patients of TICI 3 group had better prognosis than that of TICI 2b group(68.9%vs 47.4%;χ2=3.946,P=0.047).After adjusting for age,hypertension,diabetes,baseline systolic blood pressure,triglyceride,intravenous thrombolysis,ASTIN/SIR collateral circulation,TICI grade 3 was the independent predictor of 3-month favorable prognosis(OR 3.759,CI 1.098～12.871;P = 0.035)by multivariate logistic regression.Besides,both NIHSS score(OR 0.820,CI 0.715～0.941;P = 0.005)and admission glucose(OR 0.610,CI 0.410～0.906;P = 0.014)were independent predictors of 3-month poor prognosis.Conclusion:Patients of TICI reperfusion grade 3 have significantly better 3-month prognosis compared with TICI grade 2b.