关键词: 急性缺血性脑卒中, 血管内介入治疗, CT灌注成像, 低灌注强度比, 出血转化

Abstract: Objective Parenchymal hematoma （PH） is a severe type of hemorrhagic transformation and is associated with poor outcomes in patients with acute ischemic stroke after endovascular thrombectomy treatment. This study explores the relationship between hypoperfusion intensity ratio （HIR） from CT perfusion imaging with postoperative PH and clinical outcomes. Methods We analyzed the clinical and imaging data of patients with acute anterior circulation large vessel occlusion treated with endovascular intervention in our stroke center from December 2020 to December 2022. HIR was calculated as the ratio of severe hypoperfusion area volume （Tmax>10 seconds） to hypoperfusion area volume （Tmax>6 seconds） from head CT perfusion imaging. The type of hemorrhagic transformation after endovascular thrombectomy treatment was determined according to Heidelberg grading criteria. We analyzed the relationship between clinical, and imaging data with postoperative HT and clinical outcomes at discharge. Results Fifty-five patients with acute anterior circulation large vessel occlusion were included in the study. Twenty-one patients （38.2%） developed HT after thrombectomy treatment, including nine with PH. HIR at admission was significantly higher in the PH group than in the non-PH group （0.58 vs. 0.33, P=0.010）. HIR was significantly higher in the poor clinical outcome group （modified Rankin Scale 3~6 points） than in the good outcome group （0.47 vs. 0.25, P<0.001）. In addition, atrial fibrillation, NIHSS score at admission, blood glucose, neutrophil-to-platelet ratio, cerebral blood flow <30%, Tmax>10 seconds, and PH after endovascular thrombectomy were significantly associated with poor clinical outcomes. HIR（OR=1132.791, 95%CI： 7.979~160 828.706, P=0.005）was one ofthe independent factors for poor clinical outcomes. Conclusion HIR at admission is significantly associated with PH after endovascular thrombectomy, and it is an effective imaging marker for poor clinical outcomes after endovascular thrombectomyfor patients with acute anterior circulation large vessel occlusion.

Key words: acute ischemic stroke, endovascular treatment, CT perfusion imaging, hypoperfusion intensity ratio, hemorrhagic transformation