目的：使用高分辨磁共振血管壁成像（high resolution magnetic resonance vessel wall imaging， HRMR-VWI）评价大脑中动脉（middle cerebral artery，MCA）粥样硬化性狭窄斑块内出血的比例及临床相关 性。方法：收集2019年7月～2023年8月我院收治的MCA-M1或M2段中重度狭窄（50%～99%）患者的临 床及影像学资料（T1平扫脂肪抑制序列HRMR-VWI图像，斑块内出血定义为T1高信号，信号强度＞150%周 围肌肉组织信号）；根据3个月内MCA中重度狭窄供血区内是否存在缺血症状，分为症状性狭窄组和无症 状性狭窄组；症状性狭窄组再根据DWI特点分为动脉-动脉栓塞亚组和非动脉-动脉栓塞亚组。比较各组和 各亚组的临床及影像学数据。结果：最终59例患者纳入分析，其中14例（23.7%）MCA狭窄病变中可见斑块 内出血。症状性狭窄组30例（50.8%），其中斑块内出血11例（36.7%），发生率高于无症状性狭窄患者[3例 (10.3%)]，差异有统计学意义（P=0.018）。症状性狭窄患者中，11例（36.7%）患者可见动脉-动脉栓塞，其中7/ 11例（63.6%）可见斑块内出血，发生率高于非动脉-动脉栓塞患者（4/19例，21.1%），差异具有统计学差异（P= 0.047）。2组间及2亚组间其余因素差异未见明显统计学意义（均P＞0.05）。结论：症状性MCA中重度狭窄 患者斑块内出血的比例高于无症状性狭窄患者，且在症状性狭窄患者中，栓塞性梗死的患者发现斑块内出 血的比例更高，对于评估MCA狭窄患者的梗死机制及卒中风险具有重要意义。

To evaluate the proportion of intraplaque hemorrhage (IPH) and its clinical correlation in patients with atherosclerotic stenosis of the middle cerebral artery (MCA) using high-resolution magnetic resonance vessel wall imaging (HRMR-VWI). Methods: We collected clinical and imaging data from patients with moderate to severe stenosis (50%～99%) of the MCA-M1 or M2 segments treated in our hospital from July 2019 to August 2023. IPH was defined as T1 hyperintensity on fat-saturated HRMR-VWI images, with signal intensity>150% of the surrounding muscle tissue. Patients were divided into symptomatic stenosis and asymptomatic stenosis groups based on the presence of ischemic symptoms within the MCA territory within 3 months. The symptomatic stenosis group was further subdivided into artery-to-artery embolism and non-artery-to-artery embolism subgroups according to DWI characteristics. Clinical and imaging data were compared among groups and subgroups. Results: A total of 59 patients were included in the analysis, of whom 14(23.7% ) had IPH in the MCA stenosis lesions. The symptomatic stenosis group comprised 30 patients (50.8%), and the incidence of IPH in symptomatic stenosis patients was 11/30(36.7%), significantly higher than that in asymptomatic stenosis patients [3/29(10.3%)], with a statistically significant difference (P=0.018). Among symptomatic stenosis patients, 11(36.7% ) had artery-to-artery embolism, of whom 7/11(63.6% ) had IPH, a significantly higher incidence than in non-artery-to-artery embolism patients (4/19, 21.1% ), with a statistically significant difference (P=0.047). No significant differences were observed for other factors between the two groups and two subgroups (all P>0.05). Conclusion: The proportion of IPH is higher in symptomatic MCA moderate to severe stenosis patients compared to asymptomatic patients. Moreover, within the symptomatic group, patients with embolic infarction have a higher incidence of IPH. This finding is significant for evaluating the infarction mechanism and stroke risk in MCA stenosis patients.