Data Sheet 1_Hyperintense acute reperfusion marker (HARM) and thrombus analysis in acute ischemic stroke.pdf

Mechanical thrombectomy allows thrombus analysis in acute ischemic stroke. The extravasation of contrast material into the cerebrospinal fluid (CSF) on fluid-attenuated inversion recovery (FLAIR) imaging is referred to as a hyperintense acute reperfusion marker (HARM), which indicates deterioration of the blood–brain barrier (BBB). In this study, we aimed to examine the relationship between the histopathological features of thrombi and HARM in acute ischemic stroke. A total of 56 patients who underwent mechanical thrombectomy (MT) were included in the study. Procedural data, including the number of passes, techniques used, and recanalization scores based on the modified Thrombolysis in Cerebral Infarction (mTICI) scale, were documented. FLAIR imaging was performed 24 h after contrast administration. The presence of contrast extravasation into the cerebral sulci was defined as a positive HARM. A total of 52 thrombi were successfully retrieved and analyzed. Thrombus sections were stained with hematoxylin and eosin (H&E) to evaluate their fibrin and erythrocyte composition. Immunohistochemical staining using CD3, CD20, and CD45 antibodies was performed to identify T lymphocytes, B lymphocytes, and total leukocytes, respectively. In our study, it was found that clinical outcomes—measured by National Institutes of Health Stroke Scale (NIHSS) scores at 24 h and modified Rankin Scale (mRS) scores at 90 days—were significantly worse in HARM-positive patients. A histopathological analysis revealed that thrombi from HARM-positive patients were predominantly rich in fibrin, suggesting a potential association between thrombus composition and BBB disruption. Future studies incorporating more detailed thrombus characterization alongside advanced radiological markers may yield valuable insights into stroke pathophysiology.

机械取栓术（Mechanical thrombectomy）可用于急性缺血性脑卒中患者的血栓分析。在液体衰减反转恢复（Fluid-attenuated inversion recovery, FLAIR）成像中，对比剂渗入脑脊液（Cerebrospinal fluid, CSF）的现象被称为高信号急性再灌注标志物（Hyperintense acute reperfusion marker, HARM），其提示血脑屏障（Blood-brain barrier, BBB）功能受损。本研究旨在探讨急性缺血性脑卒中患者的血栓组织病理学特征与HARM之间的关联。本研究共纳入56例行机械取栓术（Mechanical thrombectomy, MT）的患者，记录手术操作相关数据，包括取栓次数、所用手术技术，以及基于改良脑梗死溶栓量表（modified Thrombolysis in Cerebral Infarction, mTICI）的再通评分。对比剂给药后24小时行FLAIR成像，将对比剂渗入脑沟的情况定义为HARM阳性。本研究共成功获取并分析52枚血栓，对血栓切片行苏木精-伊红染色（Hematoxylin and eosin, H&E）以评估其纤维蛋白与红细胞组成；采用CD3、CD20及CD45抗体进行免疫组织化学染色，分别用以鉴定T淋巴细胞、B淋巴细胞及总白细胞。本研究发现，HARM阳性患者的临床结局——以24小时美国国立卫生研究院卒中量表（National Institutes of Health Stroke Scale, NIHSS）评分及90天改良Rankin量表（modified Rankin Scale, mRS）评分评估——显著更差。组织病理学分析显示，HARM阳性患者的血栓以富含纤维蛋白为主要特征，提示血栓组成与血脑屏障破坏之间可能存在关联。未来结合更细致的血栓特征分析与先进影像学标志物的研究，或可为脑卒中病理生理学研究提供有价值的新见解。