年龄对颅内动脉粥样硬化性狭窄影响的高分辨磁共振研究

Age-related differences in high resolution magnetic resonance imaging findings in patients with middle cerebral artery atherosclerotic stenosis

目的利用HRMRI评价年龄对动脉粥样硬化性大脑中动脉狭窄血管重构和斑块负荷的影响。方法回顾性分析青年组(≤45岁)和中-老年组(>45岁)动脉粥样硬化性MCA中-重度狭窄患者的HRMRI影像学及临床特点。在HR-T1WI轴位像测量最狭窄处和参考位置的血管面积和管腔面积,根据公式计算管壁面积、斑块大小、狭窄程度,斑块负荷百分比和重构指数。重构指数≥1.0为阳性重构,<1.0为阴性重构。结果共71例患者纳入分析,青年组、中老年组阴性重构比例分别为80.83%、44.68%(P=0.037),青年组、中老年组的斑块负荷百分比分别为0.314±0.183、0.405±0.126(P=0.017)。结论颅内大动脉粥样硬化的重构方式和斑块负荷与年龄相关。动脉粥样硬化性MCA狭窄的青年组患者阴性重构比例较高,可能与吸烟、脑血管壁的独特结构特点和脑血流动力学特点有关。

Objective This study aimed to use high-resolution magnetic resonance imaging(HRMRI)to evaluate the correlation of age with vascular remodeling and plaque burden in patients with moderate-severe atherosclerotic middle cerebral artery(MCA)stenosis.Methods HRMRI and clinical characteristics of patients with atherosclerotic MCA stenosis having stenosis degree≥50%diagnosed by magnetic resonance angiography were retrospectively analyzed.According to age,the patients were divided into young(≤45 years old)and middle–old groups(>45 years old).Vessel and lumen areas in the maximal lumen narrowing and reference site were measured in the HR-T 1WI axial image,and wall area,plaque size,stenosis degree,plaque burden percentage,and remodeling index were calculated.Remodeling index≥1.0 was considered as positive remodeling and<1.0 was considered as negative remodeling.Results The negative remodeling ratio in the young and middle-old groups was 80.83%and 44.68%(P=0.037),and the plaque burden percentage was 0.314±0.183 and 0.405±0.126,respectively(P=0.017).Conclusion The remodeling pattern and plaque burden of MCA atherosclerotic stenosis were related to age.The negative remodeling ratio was higher in the young group than in the old group,and the plaque burden percentage was lower in the young group than in the old group.