分享:
分享到微信朋友圈
X
临床研究
Willis环完整性及颅颈动脉粥样硬化斑块特征与复发性卒中的相关性研究
王泽华 高阳 吴琼 何金龙 王丽雯

Cite this article as: WANG Z H, GAO Y, WU Q, et al. The recurrent stroke associated with integrity of Willis ring and characteristics of intracranial-carotid artery plaques[J]. Chin J Magn Reson Imaging, 2023, 14(12): 19-25.本文引用格式:王泽华, 高阳, 吴琼, 等. Willis环完整性及颅颈动脉粥样硬化斑块特征与复发性卒中的相关性研究[J]. 磁共振成像, 2023, 14(12): 19-25. DOI:10.12015/issn.1674-8034.2023.12.004.


[摘要] 目的 使用颅颈一体化的高分辨率磁共振血管成像(magnetic resonance angiography, MRA)检查,对前循环缺血性脑卒中患者的Willis环完整性、颅颈动脉粥样硬化斑块特征进行分析,探寻与复发性卒中独立相关的影像特征。材料与方法 回顾性分析前循环缺血性脑卒中患者87例,均在症状出现14 d内接受高分辨率磁共振血管壁成像检查,并根据临床及影像资料将其分为卒中初发组和复发组。记录斑块总数、颅颈动脉斑块特征及Willis环完整性。比较初发组、复发组之间及Willis环完整组、不完整组之间的颅颈动脉斑块特征。采用多因素logistic回归分析评估与前循环缺血性脑卒中复发相关的独立危险因素。结果 共纳入87例患者。初发组54例,复发组33例。两组间性别(P=0.223)、年龄(P=0.779)差异无均统计学意义。与初发组相比,复发组的颅内斑块强化(P=0.010)、颅内动脉狭窄程度(P=0.002)、斑块总数(P<0.001)、颅内斑块强化合并颅外斑块(P=0.006)、颅内(或颅外)动脉狭窄>50%合并颅外(或颅内)斑块(P=0.001)及Willis环后循环症状侧不完整(P<0.001)与复发性卒中显著相关。与Willis环前循环完整组相比,Willis环前循环不完整组颅内斑块强化(P=0.012)更多见。多因素logistic回归分析显示:斑块总数[比值比(odds ratio, OR)=2.14,95%置信区间(confidence interval, CI):1.182~3.869,P=0.012]和Willis环后循环症状侧不完整(OR=4.58,95% CI:1.496~14.041,P=0.008)为前循环缺血性脑卒中复发的独立危险因素。logistic回归模型的整体预测效能最佳[曲线下面积(area under the curve, AUC)=0.811,95% CI: 0.711~0.910]。结论 斑块总数和Willis环后循环症状侧不完整与前循环缺血性脑卒中复发独立相关。颅颈一体化的高分辨率磁共振血管壁成像检查可为前循环缺血性脑卒中复发预测模型的构建提供新指标。
[Abstract] Objective The integrity of Willis ring and the characteristics of Atherosclerosis plaque in the skull and neck of patients with ischemic stroke in the anterior circulation were analyzed by using magnetic resonance angiography (MRA) integrated with the skull and neck to explore the image characteristics independently related to recurrent stroke.Materials and Methods Eighty-seven patients with anterior circulation ischemic stroke were collected retrospectively. all of them were examined by high-resolution magnetic resonance angiography within 14 days after the onset of symptoms, and were divided into initial stroke group and recurrent group according to clinical and imaging data. They were divided into the initial stroke group and the recurrent stroke group based on clinical and imaging data. Record the total number of plaques, the characteristics of carotid artery plaques (intracranial: plaque enhancement, intra plaque bleeding, degree of stenosis; extracranial: lipid core, intra plaque bleeding, degree of stenosis), and the integrity of the Willis ring. Compare the characteristics of carotid artery plaques between the initial and recurrent groups. Evaluation of independent risk factors associated with recurrence of ischemic stroke in the anterior circulation using multivariate logistic regression analysis.Results A total of 87 patients were included. There are 54 cases in the initial group and 33 cases in the recurrence group. There was no statistically significant difference in gender (P=0.223) and age (P=0.779) between the two groups. Compared with the initial group, the recurrent group showed intracranial plaque enhancement (P=0.010), degree of intracranial artery stenosis (P=0.002), total number of plaques (P<0.001), intracranial plaque enhancement combined with extracranial plaques (P=0.006), intracranial (or extracranial) artery stenosis>50% combined with extracranial (or intracranial) plaques (P=0.001), and incomplete symptom side of Willis' posterior circulation (P<0.001). Significant correlation with recurrent stroke. Compared with the Willis group with intact anterior circulation, the Willis group with incomplete anterior circulation showed more enhancement of intracranial plaques (P=0.012). Multivariate logistic regression analysis showed that the total number of plaques [odds ratio (OR)=2.14, 95% confidence interval (CI): 1.182-3.869, P=0.012] and the incomplete symptomatic side of Willis' posterior circulation (OR=4.58, 95% CI: 1.496-14.041, P=0.008) were independent predictors of anterior circulation ischemic stroke recurrence. The overall prediction performance of the logistic regression model is optimal [area under the curve (AUC) =0.811, 95% CI: 0.711-0.910].Conclusions The total number of plaques and incomplete posterior circulation symptoms of Willis are independently associated with the recurrence of ischemic stroke in the anterior circulation. High resolution vascular wall magnetic resonance imaging with integrated craniocervical imaging can provide new indicators for the construction of predictive models for anterior circulation ischemic stroke recurrence.
[关键词] 脑卒中;卒中复发;磁共振成像;血管壁成像;颅颈斑块;Willis环
[Keywords] stroke;stroke recurrence;magnetic resonance imaging;vascular wall imaging;cranial carotid artery plaques;the circle of Willis

王泽华    高阳 *   吴琼    何金龙    王丽雯   

内蒙古医科大学附属医院影像诊断科,呼和浩特 010050

通信作者:高阳,E-mail:1390903990@qq.com

作者贡献声明:高阳设计本研究的方案,对稿件重要的智力内容进行了修改,获得了内蒙古自治区医疗卫生科技计划项目的基金资助;王泽华起草和撰写稿件,获取、分析或解释本研究的数据;吴琼、何金龙、王丽雯获取、分析或解释本研究的数据,对稿件重要的智力内容进行了修改,其中何金龙获得了内蒙古自治区自然科学基金项目的资助;全体作者都同意发表最后的修改稿,同意对本研究的所有方面负责,确保本研究的准确性和诚信。


基金项目: 内蒙古自治区自然科学基金项目 2023QN08055 内蒙古自治区医疗卫生科技计划项目 202201250
收稿日期:2023-07-06
接受日期:2023-11-03
中图分类号:R445.2  R543.5  R743.3 
文献标识码:A
DOI: 10.12015/issn.1674-8034.2023.12.004
本文引用格式:王泽华, 高阳, 吴琼, 等. Willis环完整性及颅颈动脉粥样硬化斑块特征与复发性卒中的相关性研究[J]. 磁共振成像, 2023, 14(12): 19-25. DOI:10.12015/issn.1674-8034.2023.12.004.

0 前言

       Willis环是一种连接大脑前后血液循环的解剖结构,正常人群中部分存在Willis环变异现象,但在脑卒中人群中其Willis环不完整率更高[1, 2]。颅颈部大血管的几何变化影响斑块的形成和分布,斑块更容易出现在动脉分叉、走行迂曲等部位,因为这些部位的血流动力学不稳定[3, 4]。而不完整的Willis环同样可以导致颅颈动脉处的壁切应力增加,提高了缺血性脑血管事件的发生率。WANG等[5]研究了Willis环完整性与缺血性脑卒中发生的相关性,发现拥有不完整Willis环的人群更容易发生缺血性脑卒中。颅颈动脉粥样硬化性疾病是导致短暂性脑缺血发作或缺血性脑卒中的主要原因。大量研究表明,颅内动脉粥样硬化性疾病和颈动脉易损斑块分别与脑血管事件相关[6, 7, 8, 9]。然而,动脉粥样硬化作为一种全身性疾病,其通常同时影响颅内外动脉。多血管床动脉粥样硬化性病变反映了动脉粥样硬化性疾病的全身负担,越来越多的证据表明,多血管粥样硬化比单一血管粥样硬化更容易发生缺血事件[10]

       既往的研究大多单独探讨颅颈动脉粥样硬化斑块特征或Willis环完整性与复发性卒中的相关性,缺乏缺血性脑卒中患者Willis环完整性、颅颈动脉粥样硬化斑块特征及共存斑块的组合研究。因此,本研究使用高分辨率磁共振血管壁成像检查对前循环缺血性脑卒中患者的斑块特征及Willis环完整性进行定性、定量评估,比较初发组与复发组斑块特征、Willis环完整性的差异,初步探讨与脑卒中复发相关的独立危险因素,为前循环缺血性脑卒中患者的个体化治疗及复发风险评估提供指导和帮助。

1 材料与方法

1.1 研究对象

       回顾性分析2022年1月到2023年5月在内蒙古医科大学附属医院就诊的前循环急性缺血性脑卒中患者的病历资料。本研究遵守《赫尔辛基宣言》,经内蒙古医科大学附属医院伦理委员会批准,全体受试者均签署了知情同意书,批准文号:KY(2022030)。本研究的纳入标准:(1)根据头颅 MRI检查证实前循环区急性缺血性脑卒中发生[扩散加权成像(diffusion-weighted imaging, DWI)示额叶、颞叶、岛叶、顶叶和基底节等区域出现高信号];(2)卒中14 d内完善了高分辨率磁共振血管壁成像检查,图像清晰血管壁可辨认;(3)经高分辨率磁共振血管壁成像检查发现颅颈动脉有动脉粥样硬化斑块形成。排除标准:(1)其他可能的缺血原因,如动脉夹层、血管炎、烟雾病或心源性栓塞等;(2)同时存在后循环缺血性脑卒中。参考XU等[11]对前循环区缺血性脑卒中患者的分组方法,陈旧性脑梗死定义为T1WI上为低信号,T2WI上为高信号,DWI相应部位未见明显高信号,根据有无陈旧性脑梗死将其分为初发组和复发组。按照Willis环完整性分2个亚组,即Willis环前循环部分完整组和Willis环前循环部分不完整组、Willis环后循环部分症状侧完整组和Willis环后循环部分症状侧不完整组(具体标准见1.3)。采集患者的一般临床资料,包括年龄、性别、高血压、糖尿病、高脂血症、吸烟史、饮酒史。临床诊断标准如下:(1)高血压病:收缩压≥140 mmHg和(或)舒张压≥90 mmHg,或目前使用降血压药物治疗;(2)糖尿病:空腹血糖≥7.0 mmol/L或目前使用降糖药物治疗;(3)高脂血症定义为总胆固醇≥6.2 mmol/L或低密度脂蛋白胆固醇≥4.1 mmol/L或甘油三酯≥1.7 mmol/L,或目前使用降胆固醇药物治疗;(4)吸烟史定义为既往每日吸烟≥10支,持续5年以上;(5)饮酒史定义为既往每月至少2次,连续一年以上。

1.2 影像学检查

       本研究采用西门子Skyra 3.0 T磁共振成像设备(Siemens Healthcare, Erlangen, Germany),32通道头颈动脉联合线圈。高分辨率血管壁磁共振扫描采用3D T1-SPACE序列,矢状位扫描,扫描范围从颅顶部到颈动脉分叉下方,参数如下:TR 900 ms,TE 20 ms,FOV 205 mm×160 mm,层厚0.53 mm,层数256,矩阵300×384。使用高压注射器注射对比剂5 min后进行重复扫描,对比剂为钆喷酸葡胺(北京北陆药业股份有限公司,中国),注射剂量为0.2 mL/kg,流速4 mL/s。时间飞跃法磁共振血管成像(time of flight magnetic resonance angiography, TOF-MRA)扫描范围同样从颅顶部到颈动脉分叉下方,参数:TR 21 ms,TE 3.43 ms,FOV 220 mm×199 mm,激励次数1,矩阵320×191。临床常规扫描头颅MRI,包括横轴位T1WI 液体衰减反转恢复(fluid attenuated inversion recovery, FLAIR)序列、T2WI快速自旋回波(fast spin echo, FSE)序列、DWI序列,矢状位T1WI序列。

1.3 图像后处理及分析方法

       应用医学图像处理软件(Vessel Analysis, 版本1.0,北京,中国)的曲面重建(curved planar reformation, CPR)功能进行重建,获取病变血管的横断面图像进行分析。按照CUI等[10]对颅内外动脉的定义,颅外动脉包括颈总动脉末端、颈内动脉C1~C2段;颅内动脉包括颈内动脉C3~C7段、大脑中动脉M1段、大脑前动脉A1段。记录每位患者上述动脉的斑块总数。其余指标如下:(1)斑块强化,斑块强化程度分为3级。0级,斑块强化信号低于或等于正常无斑块颅内动脉的管壁信号;1级,斑块强化信号大于0级,但小于该患者垂体柄强化信号;2级,斑块强化信号等于或大于垂体柄强化信号[12]。强化程度为 1 级或 2 级的斑块定义为强化斑块。(2)斑块内出血,在3D T1-SPACE序列上采用感兴趣区(region of interest, ROI)测量工具,手动测量斑块及邻近正常参考管壁的信号,斑块内高信号区域信号强度>150%参考管壁信号强度,则认为存在IPH[13]。(3)脂质核心,TOF-MRA上为等信号,平扫3D T1-SPACE上为高信号,增强3D T1-SPACE上为低信号。(4)狭窄率,颅内动脉参照华法林-阿司匹林症状性颅内动脉疾病试验法[14]、颅外颈动脉参照北美症状性颈动脉内膜剥脱试验法[15],在高分辨率磁共振血管壁成像图像上进行测量。(5)Willis环分型,参照之前公布的标准,使用TOF-MRA的原始图像及最大密度投影图将Willis环分为4型。Ⅰ型,Willis环前循环部分完整;Ⅱ型,Willis环前循环部分不完整;Ⅲ型,Willis环后循环部分症状侧完整;Ⅳ型,Willis环后循环部分症状侧不完整[16, 17]。(6)梗死数量,根据 DWI 图像检测到的症状侧高信号病变的数量将患者分为单发梗死和多发梗死[18]。多发梗死是指症状侧发生一个以上的非连续性病变。(7)责任斑块,卒中血管区域内的唯一斑块或多个斑块存在于发生卒中的供血区域内时最狭窄层面的斑块;当多个斑块存在于卒中供血区域内且狭窄程度相近时,则无法确定责任斑块位置[19]。动脉粥样硬化性斑块定义为以病变所在血管邻近或对侧的正常无斑块血管节段为参考,斑块为局灶性的血管壁增厚,不论是否引起管腔狭窄。以上测量过程由2位经验丰富的高年资副主任医师共同完成,分析时均不知晓患者是否有缺血性脑卒中复发史。

1.4 统计学分析

       应用SPSS PRO在线统计分析平台进行统计分析。使用柯尔莫戈洛夫-斯米诺夫检验法检验定量资料的正态性,符合正态分布的计量资料采用均数±标准差表示,不符合正态分布的采用中位数(四分位数间距)表示,计数资料采用例(%)表示。符合正态分布的计量资料的组间比较采用独立样本t检验,不符合正态分布采用非参数秩和检验,计数资料采用卡方检验。所有检验均为双侧检验。单因素logistic回归和LASSO回归用于变量筛选。所选择的变量被纳入多因素logistic回归,采用基于最大似然估计的向前逐步回归法,以获得与脑卒中复发相关的独立危险因素。采用组间相关系数评估影像参数测量的再现性,对于阅片者之间,采用双因子随机效应评估一致性。对多因素logistic回归得到的独立危险因素计算受试者工作特征(receiver operating characteristic, ROC)曲线相应的曲线下面积(area under the curve, AUC)值。双尾P<0.05被认为差异具有统计学意义。

2 结果

2.1 一般资料

       共纳入87例患者,其中初发组共54例,男38例,年龄66(55, 70)岁;复发组共33例,男19例,年龄63(59, 67)岁。两组患者间临床资料的差异均无统计学意义(P均>0.05),见表1

表1  初发组及复发组患者临床资料及影像特征比较
Tab. 1  Comparison of clinical data and imaging features between the initial and recurrent groups of patients

2.2 初发组与复发组颅颈斑块特征、共存斑块特征及Willis环完整性比较

       初发组与复发组颅颈斑块特征及Willis环完整性见表1。与初发组相比,复发组的颅内斑块强化(P=0.010)、颅内动脉狭窄程度(P=0.002)、斑块总数(P<0.001)、颅内斑块强化合并颅外斑块(P=0.006)、颅内(或颅外)动脉狭窄>50%合并颅外(或颅内)斑块(P=0.001)及Willis环后循环症状侧不完整(P<0.001)与复发性卒中显著相关。而其他指标在两组间差异无统计学意义(P均>0.05)。所有影像指标的阅片者内部及阅片者之间的一致性较好,组间相关系数均≥0.86。图1为复发性卒中典型病例的影像图像;图2为初发性卒中典型病例的影像图像。

图1  女,65岁,右侧下肢体无力6 d入院,患者为复发性卒中。时间飞跃法磁共振血管成像显示Willis环前循环部分完整,Willis环后循环症状侧不完整(1A);T1WI和T2WI显示双侧基底节区软化灶(1B、1D);扩散加权成像显示左侧侧脑室后角旁脑梗死(图1C);3D T1-SPACE的曲面重建图像(平扫图1E、1G、增强图1F、1H)分别显示左/右侧颅颈动脉斑块(箭);3D T1-SPACE的重建轴位图像(1I、1K)分别显示平扫时的左/右侧最狭窄处斑块,均位于大脑中动脉;1J、1L分别显示增强后的最狭窄处斑块。该患者斑块总数为4,颅内斑块发生2级强化。
Fig. 1  A 65-year-old female with right lower limb weakness was admitted for 6 days, the patient had a recurrent stroke. TOF-MRA shows that the anterior circulation of the Willis ring is partially intact, while the symptomatic side of the posterior circulation of the Willis ring is incomplete (1A); T1WI and T2WI shows bilateral softening foci in the basal ganglia (1B, 1D); diffusion-weighted imaging shows left lateral ventricles parahorn cerebral infarction (1C); the reconstructed axial images of 3D T1-SPACE (1I and 1K) show the most stenotic plaques on the left/right side during plain scan, both located in the middle cerebral artery; the 3D T1-SPACE surface reconstruction images (flat scan images 1E, 1G, enhanced images 1F, 1H) show left/right carotid artery plaques (arrows), respectively; 1J and 1L show the most stenotic plaques after enhancement, respectively. The total number of plaques in this patient is 4, and the intracranial plaques have intensified.
图2  男,46岁,右侧下肢体无力7 d入院,患者为初发性卒中。时间飞跃法磁共振血管成像显示Willis环前循环部分完整,Willis环后循环症状侧完整(2A);扩散加权成像显示左侧半卵圆中心急梗(2B);3D T1-SPACE的曲面重建图像(平扫图2C、2E,增强图2D、2F)分别显示左/右侧颅颈动脉斑块(箭);3D T1-SPACE的重建轴位图像(2G、2I)分别显示平扫时的左/右侧最狭窄处斑块,均位于颈内动脉分叉处;2H、2J分别显示增强后的最狭窄处斑块。该患者斑块总数为2。
Fig. 2  A 46 years old male with right lower limb weakness was admitted for 7 days, the patient had a primary stroke. TOF-MRA shows that the anterior circulation of the Willis ring is complete, while the symptomatic side of the posterior circulation of the Willis ring is complete (2A); DWI shows acute myocardial infarction in the left half oval center (2B); the 3D T1-SPACE surface reconstruction images (flat scan images 2C and 2E, enhanced images 2D and 2F) show left/right carotid artery plaques (arrows), respectively; the reconstructed axial images of 3D T1-SPACE (2G and 2I) show the most stenotic plaques on the left/right side during plain scan, both located at the bifurcation of the internal carotid artery; 2H and 2J show the most stenotic plaques after enhancement, respectively. The total number of plaques in this patient is 2.

2.3 Willis完整组与Willis不完整组颅颈斑块特征比较

       与Willis环前循环部分完整组相比,Willis环前循环部分不完整组的颅内斑块强化(P=0.012)更多见,而其他指标在两组间差异无统计学意义(P均>0.05)。Willis环后循环部分完整组和Willis环后循环部分不完整组两组患者间颅颈斑块特征的差异均无统计学意义(P均>0.05),详见表2

表2  A-CoW组与IA-CoW组、SP-CoW组与ISP-CoW患者颅颈斑块特征比较
Tab. 2  Comparison of the characteristics of craniocervical plaques between A-CoW group and IA-CoW group patients, SP-CoW group and ISP-CoW group patients

2.4 脑卒中复发的独立危险因素

       脑卒中复发的独立危险因素见表3,斑块强化、斑块总数、Willis环后循环部分不完整、颅内(或颅外)动脉狭窄>50%合并颅外(或颅内)斑块被确定为多因素分析的输入变量。分析显示,斑块总数(OR=2.14,95% CI:1.182~3.869, P=0.012)和Willis环后循环症状侧不完整(OR=4.58,95% CI:1.496~14.041, P=0.008)与卒中复发独立相关。斑块总数和Willis环后循环症状侧不完整两者联合模型的预测效能(AUC=0.811,95% CI:0.711~0.910)高于任一单独预测因素,如斑块总数(AUC=0.754,95% CI: 0.650~0.859),Willis环后循环症状侧不完整(AUC=0.694,95% CI:0.578~0.811)。

表3  与复发性卒中独立相关的影像学特征
Tab. 3  Imaging features independently associated with recurrent stroke

3 讨论

       本研究使用高分辨率磁共振血管壁成像分析Willis环完整性、颅颈动脉粥样硬化斑块特征与复发性卒中的相关性,并分析Willis环完整性与颅颈动脉粥样硬化斑块特征的相关性。研究结果表明斑块总数增长及Willis环后循环症状侧不完整可增加脑卒中复发的风险;Willis环前循环部分不完整组的颅内斑块更容易发生强化,而Willis环后循环部分不完整与颅颈动脉粥样硬化斑块特征无明显相关性。

3.1 颅颈动脉粥样硬化斑块特征在缺血性脑卒中复发中的预测价值

       动脉粥样硬化是一种系统性疾病,可影响多个血管床。两项大型前瞻性研究证明,在磁共振血管成像或数字减影血管造影术上存在多发性颅内动脉粥样硬化性狭窄或同时存在颅外动脉粥样硬化,是卒中复发的独立预测因素[20, 21, 22]。多项高分辨率磁共振血管壁成像研究显示,同时累及颅内外动脉的多血管床动脉粥样硬化是后续血管事件(特别是卒中复发)的高危因素[23, 24]。以上研究分析了共存斑块的存在与卒中复发的相关性以及颅内动脉狭窄合并颅外动脉斑块特征与卒中的相关性,均未考虑颅内斑块特征合并颅外动脉粥样硬化与卒中的相关性。众所周知,与血管造影成像方法相比,高分辨率磁共振血管壁成像可以提供更多的动脉壁病变的直接信息。在本研究中,颅颈动脉斑块的存在均通过高分辨率磁共振血管壁成像来确定,70%的有症状患者颅内和颅外动脉粥样硬化性疾病并存。我们的发现比以前的报告患病率更高,在以往有症状的患者中,共存斑块的患病率从42.2%到64%不等[25, 26]。与前人的研究不同,XU等[11]应用高分辨率磁共振血管壁成像检测动脉粥样硬化性疾病,发现症状性患者颅内外斑块并存的发生率为77.6%。本研究中共存的脑血管动脉粥样硬化斑块的患病率略低于XU等的结果,这可能是由于不同的研究人群所致。在XU等的研究中,所有患者的颈动脉至少一侧有斑块;颅内外血管床并存斑块的存在进一步证明动脉粥样硬化可以全身性发展。本研究利用3D T1-SPACE探讨了颅颈动脉斑块特征及共存斑块特征和前循环缺血性脑卒中复发的关系,发现斑块总数与前循环缺血性脑卒中复发独立相关,进一步说明了存在多血管床动脉粥样硬化性病变的卒中患者复发风险可能更高。而斑块强化、斑块内出血等易损斑块特征经过多因素分析后,并未发现其与前循环缺血性脑卒中复发有明显相关性,这与YANG等[27]单独分析颅颈责任斑块特征的研究结论相悖,其认为斑块强化是复发性卒中的重要独立危险因素。这可能是因为本研究不局限于责任斑块特征,把多血管病变及Willis环完整性等影响血流动力学的因素都考虑了进去,更证明了之后研究应进一步着眼于系统性动脉粥样硬化、脑灌注、侧支循环及多病因重叠等方面,致力于构建多方位的卒中复发预测模型。

3.2 Willis环完整性与易损斑块特征及缺血性脑卒中复发的相关性分析

       脑血流侧支循环主要依赖于Willis环,特别是在脑缺血需要侧支循环代偿的情况下[28]。然而,在正常人群中,Willis环也存在不同程度的先天性变异[29, 30]。先前的研究表明,当颅颈动脉无狭窄时,前交通动脉无血流通过;随着颅颈动脉狭窄程度的增加,前交通动脉血流率也逐步升高[31]。而颅颈动脉狭窄程度的增加也会导致狭窄局部管壁处的壁切应力增加,管壁发生重塑,加大了斑块破裂的风险[32, 33, 34]。因此,当Willis环前循环部分不完整,特别是缺乏前交通动脉时,Willis环就不能有效调节狭窄动脉处的血压,从而进一步加重了斑块内新生血管处的壁切应力,最终新生血管发生破裂导致斑块内出血;较高的壁切应力也会诱发斑块内炎症反应的进展,促进毛细血管生成,提高血管内皮细胞通透性,导致斑块发生强化。本研究也验证了这一机理,与Willis环前循环部分完整组相比,Willis环前循环部分不完整组的颅内斑块强化更多见。本研究还发现Willis环后循环症状侧不完整与卒中复发独立相关。这一结果表明后交通动脉也是影响前循环缺血性脑卒中预后的重要因素。后交通动脉也是许多穿支动脉(如丘脑前动脉)的起源[35]。当大脑中动脉或颈内动脉中重度狭窄合并Willis环后循环症状侧不完整时,大脑缺血症状往往会更加严重[36, 37, 38]。因此,对于Willis环后循环症状侧不完整的高危人群,应密切观察其颅颈动脉粥样硬化的进展,实施早期临床干预治疗。

3.3 局限性与展望

       本研究仍有局限:首先,这是一个回顾性研究,有必要进行前瞻性研究,分析颅颈动脉粥样硬化斑块特征的纵向变化对缺血性事件的预测价值;其次,我们仅招募了前循环缺血性脑卒中患者,之后应将后循环缺血性脑卒中患者也纳入进来;最后,本次研究样本量较小,未来的研究需要更大的样本量。

4 结论

       综上所述,斑块总数和Willis环后循环症状侧不完整与前循环缺血性脑卒中复发独立相关;联合临床资料、颅颈斑块特征及Willis环完整性的复发性卒中预测模型应是日后的重点研究方向。颅颈一体化的高分辨率磁共振血管壁成像检查可为缺血性脑卒中复发预测模型的构建提供新指标。

[1]
JONES J D, CASTANHO P, BAZIRA P, et al. Anatomical variations of the circle of Willis and their prevalence, with a focus on the posterior communicating artery: A literature review and meta-analysis[J]. Clin Anat, 2021, 34(7): 978-990. DOI: 10.1002/ca.23662.
[2]
PIECHNA A, CIESLICKI K. Influence of hydrodynamic and functional nonlinearities of blood flow in the cerebral vasculature on cerebral perfusion and autoregulation pressure reserve[J]. Sci Rep, 2023, 13(1): 16-29. DOI: 10.1038/s41598-023-32643-z.
[3]
ZHU G, YUAN Q, YANG J, et al. Experimental study of hemodynamics in the circle of Willis[J]. Biomed Eng, 2015, 14(1): 10-19. DOI: 10.1186/1475-925X-14-S1-S10.
[4]
WOO H G, KIM H G, LEE K M, et al. Wall shear stress associated with stroke occurrence and mechanisms in middle cerebral artery atherosclerosis[J]. J Stroke, 2023, 25(1): 132-140. DOI: 10.5853/jos.2022.02754.
[5]
WANG H, SHEN L, ZHAO C, et al. The incomplete circle of Willis is associated with vulnerable intracranial plaque features and acute ischemic stroke[J]. J Cardiovasc Magn Reson, 2023, 25(1): 23-31. DOI: 10.1186/s12968-023-00931-2.
[6]
ZHANG D, WU X, TANG J, et al. Hemodynamics is associated with vessel wall remodeling in patients with middle cerebral artery stenosis[J]. Eur Radiol, 2021, 31(7): 5234-5242. DOI: 10.1007/s00330-020-07607-w.
[7]
ZHANG D F, WU X Y, ZHANG W D, et al. The relationship between patterns of remodeling and degree of enhancement in patients with atherosclerotic middle cerebral artery stenosis: A High-resolution MRI study[J]. Neurol India, 2021, 69(6): 1663-1669. DOI: 10.4103/0028-3886.333443.
[8]
YAN X, GAO J, TANG M, et al. Combined assessment of elevated plasma lipoprotein-associated phospholipase A2 and plaque enhancement improved accuracy in the risk of acute ischemic stroke in patients with intracranial artery stenosis[J]. J Stroke Cerebrovasc Dis, 2021, 30(12): 86-103. DOI: 10.1016/j.jstrokecerebrovasdis.2021.106103.
[9]
SONG X, ZHAO X, LIEBESKIND D S, et al. Incremental value of plaque enhancement in predicting stroke recurrence in symptomatic intracranial atherosclerosis[J]. Neuroradiology, 2020, 62(9): 1123-1131. DOI: 10.1007/s00234-020-02418-8.
[10]
CUI B, YANG D, ZHENG W, et al. Plaque enhancement in multi-cerebrovascular beds associates with acute cerebral infarction[J]. Acta Radiol, 2021, 62(1): 102-112. DOI: 10.1177/0284185120915604.
[11]
XU Y, YUAN C, ZHOU Z, et al. Co-existing intracranial and extracranial carotid artery atherosclerotic plaques and recurrent stroke risk: a three-dimensional multicontrast cardiovascular magnetic resonance study[J]. J Cardiovasc Magn Reson, 2016, 18(1): 90-99. DOI: 10.1186/s12968-016-0309-3.
[12]
XIAO J, SONG S S, SCHLICK K H, et al. Disparate trends of atherosclerotic plaque evolution in stroke patients under 18-month follow-up: a 3D whole-brain magnetic resonance vessel wall imaging study[J]. Neuroradiol J, 2022, 35(1): 42-52. DOI: 10.1177/19714009211026920.
[13]
LIU S, TANG R, XIE W, et al. Plaque characteristics and hemodynamics contribute to neurological impairment in patients with ischemic stroke and transient ischemic attack[J]. Eur Radiol, 2021, 31(4): 2062-2072. DOI: 10.1007/s00330-020-07327-1.
[14]
SEN S, MEYER J, MASCARI R, et al. Association of Dental Infections with Intracranial Atherosclerotic Stenosis[J]. Cerebrovasc Dis, 2023, 8(1): 9-19. DOI: 10.1159/000530829.
[15]
WEI H, WANG Y, ZHANG Y, et al. Outcomes and risk factors of perforating and non-perforating middle cerebral artery infarctions after intravenous thrombolysis[J]. J Thromb Thrombolysis, 2022, 53(3): 722-730. DOI: 10.1007/s11239-021-02620-2.
[16]
ZHOU C, YUAN C, LI R, et al. Association Between Incomplete Circle of Willis and Carotid Vulnerable Atherosclerotic Plaques[J]. Arterioscler Thromb Vasc Biol, 2018, 38(11): 2744-2749. DOI: 10.1161/ATVBAHA.118.311797.
[17]
刘相城, 黄菊华, 刘春柏, 等. Willis环完整性与急性缺血性脑卒中静脉溶栓早期疗效的相关性[J]. 中国老年学杂志, 2022, 42(11): 2628-2630. DOI: 10.3969/j.issn.1005-9202.2022.11.008.
LIU X C, HUANG J H, LIU C B, et al. Association of Willis ring integrity with early efficacy of intravenous thrombolysis in acute ischemic stroke[J]. Chin J Gero, 2022, 42(11): 2628-2630. DOI: 10.3969/j.issn.1005-9202.2022.11.008.
[18]
MA Z, HUO M, XIE J, et al. Wall characteristics of atherosclerotic middle cerebral arteries in patients with single or multiple infarcts: A high-resolution MRI study[J]. Front Neurol, 2022, 13(1): 926-934. DOI: 10.3389/fneur.2022.934926.
[19]
MEN X, HU M, GUO Z, et al. Culprit plaques of large parent arteries, rather than cerebral small vessel disease, contribute to early neurological deterioration in stroke patients with intracranial branch atheromatous disease[J]. Cerebrovasc Dis, 2023, 8(1): 79-87. DOI: 10.1159/000530371.
[20]
SUN P, LIU L, PAN Y, et al. Intracranial atherosclerosis burden and stroke recurrence for symptomatic intracranial artery stenosis (sICAS)[J]. Aging Dis, 2018, 9(6): 1096-1102. DOI: 10.14336/AD.2018.0301.
[21]
ZHAO J, LI X, CHI L X, et al. Concomitant asymptomatic intracranial atherosclerotic stenosis increase the 30-day risk of stroke in patients undergoing symptomatic intracranial atherosclerotic stenosis stenting[J]. J Stroke Cerebrovasc Dis, 2018, 27(2): 479-485. DOI: 10.1016/j.jstrokecerebrovasdis.2017.09.032.
[22]
RODRIGUEZ-GRANILLO G A, CIRIO J J, CIARDI C, et al. Epicardial and periaortic fat characteristics in ischemic stroke: Relationship with stroke etiology and calcification burden[J]. Eur J Radiol, 2022, 14(1): 90-102. DOI: 10.1016/j.ejrad.2021.110102.
[23]
LI D, DAI W, CAI Y, et al. Atherosclerosis in stroke-related vascular beds and stroke risk: A 3-D MR vessel wall imaging study[J]. Ann Clin Transl Neurol, 2018, 5(12): 1599-1610. DOI: 10.1002/acn3.673.
[24]
JIANG C, ZHANG J, ZHU J, et al. Association between coexisting intracranial artery and extracranial carotid artery atherosclerotic diseases and ipsilateral cerebral infarction: a Chinese atherosclerosis risk evaluation (CARE-II) study[J]. Stroke Vasc Neurol, 2021, 6(4): 595-602. DOI: 10.1136/svn-2020-000538.
[25]
YANG F, LIU L, LI M, et al. Pattern of cerebrovascular atherosclerotic stenosis in older Chinese patients with stroke[J]. J Clin Neurosci, 2013, 20(7): 979-983. DOI: 10.1016/j.jocn.2012.09.017.
[26]
LEE S J, CHO S J, MOON H S, et al. Combined extracranial and intracranial atherosclerosis in Korean patients[J]. Arch Neurol, 2003, 60(11): 1561-1564. DOI: 10.1001/archneur.60.11.1561.
[27]
YANG D, LIU J, YAO W, et al. The MRI enhancement ratio and plaque steepness may be more accurate for predicting recurrent ischemic cerebrovascular events in patients with intracranial atherosclerosis[J]. Eur Radiol, 2022, 32(10): 7004-7013. DOI: 10.1007/s00330-022-08893-2.
[28]
JAIN C, KUMAR A, VYAS S, et al. Asymmetry in cerebral perfusion from circle of Willis arterial variations in normal population[J]. Neuroradiol J, 2023, 36(1): 31-37. DOI: 10.1177/19714009221098366.
[29]
ENYEDI M, SCHEAU C, BAZ R O, et al. Circle of Willis: anatomical variations of configuration. A magnetic resonance angiography study[J]. Folia Morphol, 2023, 82(1): 24-29. DOI: 10.5603/FM.a2021.0134.
[30]
ZHENG R, HAN Q, HONG W, et al. Hemodynamic characteristics and mechanism for intracranial aneurysms initiation with the circle of Willis anomaly[J]. Comput Methods Biomech Biomed Engin, 2023, 18(1): 1-9. DOI: 10.1080/10255842.2023.2199902.
[31]
LENG X, LEUNG T W. Collateral flow in intracranial atherosclerotic disease[J]. Transl Stroke Res, 2023, 14(1): 38-52. DOI: 10.1007/s12975-022-01042-3.
[32]
ZHANG X, JIAO Z, HUA Z, et al. Localized elevation of wall shear stress is linked to recent symptoms in patients with carotid stenosis[J]. Cerebrovasc Dis, 2023, 52(3): 283-292. DOI: 10.1159/000526872.
[33]
ZHOU M, YU Y, CHEN R, et al. Wall shear stress and its role in atherosclerosis[J]. Front Cardiovasc Med, 2023, 10(1): 108-117. DOI: 10.3389/fcvm.2023.1083547.
[34]
CHEN Z, QIN H, LIU J, et al. Characteristics of wall shear stress and pressure of intracranial atherosclerosis analyzed by a computational fluid dynamics model: A pilot study[J]. Front Neurol, 2019, 10(1): 63-72. DOI: 10.3389/fneur.2019.01372.
[35]
LAPRAZ P, PINSARD Q, COUDERT R, et al. Association between flow patterns of the posterior cerebral arterial circle and basilar-tip aneurysms[J]. Surg Radiol Anat, 2023, 45(5): 505-511. DOI: 10.1007/s00276-023-03121-y.
[36]
LIU S, HUANG Z L, SUN Y R, et al. Application value of transcranial contrast-enhanced ultrasonography in evaluating middle cerebral artery stenosis[J]. Eur Rev Med Pharmacol Sci, 2023, 27(1): 224-232. DOI: 10.26355/eurrev_202301_30875.
[37]
ZHANG B, WANG G, GAO Y, et al. Influence of the integrity of circle of Willis on asymptomatic or mild patients with first diagnosed chronic internal carotid artery occlusion[J]. Eur J Radiol, 2023, 16(5): 47-54. DOI: 10.1016/j.ejrad.2023.110954.
[38]
温宏峰, 赵春霞, 贺大权. Willis环不同代偿能力对颈动脉重度狭窄患者脑血流灌注差异的对比研究[J]. 中华老年心脑血管病杂志, 2023, 25(3): 268-271. DOI: 10.3969/j.issn.1009-0126.2023.03.011.
WEN H F, ZHAO C X, HE D Q. Comparison of cerebral blood flow perfusion in patients with severe carotid artery stenosis by different compensatory capacities of COW[J]. Chin J Geriatr Heart Brain Vessel Dis, 2023, 25(3): 268-271. DOI: 10.3969/j.issn.1009-0126.2023.03.011.

上一篇 高海拔地区轻度认知障碍患者脑结构改变的分析
下一篇 预测胶质瘤复发和术后生存期的MRI影像组学初步研究
  
诚聘英才 | 广告合作 | 免责声明 | 版权声明
联系电话:010-67113815
京ICP备19028836号-2