Abstract: Objective To compare the characteristics of HR MR vessel wall imaging (HR-MRVWI) of culprit artery in young patients and middle-aged and elderly patients with acute middle cerebral artery (MCA) occlusion after recanalization. Methods This retrospective study enrolled the patients with acute MCA occlusion who underwent mechanical recanalization in Department of Neurosurgery of Shenzhen Bao'an People's Hospital from June 2015 to June 2018. The clinical data such as general information, laboratory examination, NIHSS score, HR-MRVWI, mRS score were collected. Taking 45 years as the age limit, the patients were divided into young group (≤45 years) and middle-aged and elderly group (>45 years). The degree of stenosis, vessel wall remodeling index, plaque thickness and enhancement rate of the culprit MCA at 4 weeks and 6 months after recanalization and 1-year prognosis between the two groups were compared. Good prognosis was defined as a mRS score of 0 to 3. Results A total of 30 patients were included, with 16 cases in young group and 14 cases in middle-aged and elderly group. There were no statistical differences in stenosis rate, remodeling

index, plaque thickness and enhancement rate of MCA between the two groups at 4 weeks after

recanalization. The degree of MCA stenosis [(37.47±0.04)% vs (60.00±0.26)%, P =0.024], plaque thickness (0.63±0.18 mm vs 1.56±0.35 mm, P =0.016) and enhancement rate [(0.35±0.17)% vs (0.57±0.24)%, P =0.043] of the young group were significantly lower than those of the middleaged and elderly group at 6 months. There were no statistical differences in the remodeling rate at 6 months and mRS scores at 1 year between the two groups. Conclusions Compared to the young patients, the degree of stenosis, plaque thickness and enhancement rate of culprit MCA were higher in the middle-aged and elderly patients, suggesting that age may be an important contributing factor for plaque progression.

Key words: Acute middle cerebral artery occlusion; High-resolution magnetic resonance vessel
wall imaging; Atherosclerosis; Mechanical thrombectomy; Prognosis

摘要： 目的 比较青年和中老年大脑中动脉急性闭塞患者动脉机械取栓血管再通后HR-MRI血管壁成像 的特点。 方法 回顾性纳入2015年6月-2018年6月在深圳市宝安人民医院神经外科确诊并行大脑中动脉急 性闭塞机械取栓治疗患者的资料。根据患者入院时年龄分为青年组（≤45岁）和中老年组（＞45岁）， 比较两组机械取栓血管再通术后4周和6个月患侧大脑中动脉的HR-MRI血管壁成像特点（管腔狭窄率、 管壁重构指数、动脉粥样硬化斑块厚度及斑块强化率）及1年预后情况（mRS≤3分为预后良好）。 结果 共纳入30例患者，其中青年组16例，中老年组14例。机械取栓血管再通术后4周，两组责 任侧大脑中动脉管腔狭窄率、重构指数、动脉粥样硬化斑块厚度及斑块强化率比较差异无统计 学意义。机械取栓血管再通术后6个月，青年组治疗侧大脑中动脉管腔狭窄率（37.47%±0.04% vs 60.00%±0.11%，P =0.024）、动脉粥样硬化斑块厚度（0.63±0.18 mm vs 1.56±0.35 mm，P =0.016）及 斑块强化率（0.35%±0.17% vs 0.57%±0.24%，P =0.043）低于中老年组。两组间术后6个月时管壁重 构指数和1年良好预后率差异均无统计学意义。 结论 与青年相比，中老年患者患侧大脑中动脉机械取栓再通术后的管腔狭窄程度、动脉粥样硬 化斑块厚度及斑块强化率更高，提示年龄可能是脑血管动脉粥样硬化斑块进展的影响因素。

关键词: 大脑中动脉急性闭塞; 高分辨磁共振血管壁成像; 动脉粥样硬化; 机械取栓; 预后