深穿支动脉和浅表穿支动脉供血区梗死病人颅内动脉管壁特征的高分辨力MRI研究

目的应用全脑高分辨MRI(HRMRI)技术比较分析大脑中动脉浅表穿支动脉区梗死(SPI)和深穿支动脉区梗死(DPI)病人的颅内动脉管壁特征,以阐述其潜在的发病机制。方法回顾性分析41例[男31例,女10例;平均年龄(51.9±11.33)岁]急性期SPI和DPI行全脑HRMRI检查的病人,HRMRI采用优化的3D可变翻转角度快速自旋回波T1加权(3D T1SPACE)序列。分析梗死供血区血管动脉粥样硬化斑块的存在情况,分别测量斑块最狭窄层面的狭窄程度、重构指数以及斑块强化情况;计量资料的组间比较采用t检验或Mann-Whitney U检验,计数资料的组间比较采用χ2检验,P0.05为差异有统计学意义。结果 41例病人中,SPI 14例(34.1%),DPI27(65.9%)例。SPI组中,共13例(92.9%)病人存在颅内动脉粥样硬化斑块,DPI组有15例(55.6%),SPI病人颅内动脉粥样硬化斑块的发生率高于DPI病人(P=0.038);SPI病人管腔狭窄程度大于DPI病人(71.20%±29.46%和44.01%±28.24%,P=0.019),两组间重构指数和斑块强化情况无统计学差异(P=0.865,0.538)。结论 DPI可能由小血管疾病或载体动脉斑块堵塞穿支引起,而SPI主要由大动脉粥样硬化疾病引起,这两种梗死模式具有不同的管腔狭窄程度。     

颅内动脉粥样斑块易损性的高分辨力MRI研究

目的采用三维T1WI可变翻转角快速自旋回波(3D T1WI SPACE)序列探讨颅内粥样斑块强化及其管壁重构模式与急性脑缺血发作的关联。方法收集2016年4月—12月间天津医科大学总医院收治的29例急性脑缺血发作的住院病人,其中男25例,女4例,年龄41~80岁,平均(61.7±9.8)岁。所有病人均行3D T1WI SPACE序列检查,评估颅内粥样斑块强化特点,分析颅内动脉管壁重构方式并测量斑块负荷。采用两样本t检验比较责任斑块与非责任斑块强化程度、负荷及动脉管壁重构方式的差异,采用χ~2检验比较责任斑块与非责任斑块处管壁正性重构发生率及2级强化出现率的差异。结果 29例病人发现颅内斑块81个,其中责任斑块29个,非责任斑块52个。责任斑块2级强化出现率明显高于非责任斑块(χ~2=30.73,P=0.001)。责任斑块强化程度明显高于非责任斑块,其强化程度差异有统计学意义(t=7.30,P0.001)。责任斑块与非责任斑块处管壁正性重构发生率和重构比差异均无统计学意义(分别为χ~2=3.23,P=0.072;t=-1.19,P=0.241),而责任斑块负荷明显高于非责任斑块(t=4.59,P0.001)。结论颅内责任斑块多呈显著强化,斑块显著强化可能是颅内易损性斑块重要指征之一,这可能对病人急性脑梗死发生做出风险评估,改善其预后。     

症状性缺血性脑卒中颈动脉斑块成分的 高分辨MRI分析

目的应用高分辨MRI(HRMRI)探讨颈动脉斑块不同成分在症状性缺血性脑卒中病人中的危险性。方法选取2016年1月—2017年6月于我院行超声检查发现存在颈动脉斑块的病人50例,其中女21例,男29例,年龄43~77岁,平均(61.62±7.96)岁。依据病人近3个月来是否发生过与患侧颈动脉相关的缺血性脑卒中临床症状分为有症状组(22例,存在斑块血管40支)及无症状组(28例,50支),所有病人行3.0 T HRMRI以评估颈动脉血管及斑块内成分。采用χ~2检验或t检验对2组病人的临床资料、斑块成分及血管管腔狭窄程度进行比较,采用logistic回归分析缺血性脑卒中病人症状的独立危险因素。结果检出存在斑块纤维帽破溃(FCR)的血管,症状组15支,检出率为37.5%,无症状组8支,检出率为16.0%,症状组FCR的检出率高于无症状组(P0.05)。检出斑块内出血(IPH)的血管,症状组21支,检出率为52.5%,无症状组15支,检出率为30.0%,症状组IPH的检出率高于无症状组(P0.05)。检出存在斑块钙化(CA)的血管,症状组15支,检出率为37.5%,无症状组13支,检出率为26.0%,2组间检出率差异无统计学意义(P0.05)。症状组管腔狭窄程度为57.64%±13.36%,无症状组为53.86%±11.19%,2组间管腔狭窄程度差异无统计学意义(t=1.460,P=0.148)。FCR在症状性缺血性脑卒中危险性最高(OR=3.012),IPH危险性次之(OR=2.478)。结论 HRMRI可以分析斑块内成分,而这些成分是缺血性脑卒中临床症状发生的危险因素,是斑块易损性的表现。     

MD-CTA对颈动脉不同类型粥样斑块血管壁强化特征的研究

目的通过分析动脉粥样硬化(AS)血管壁的强化特征,评价血管壁强化程度与斑块稳定性之间的关系。资料与方法212例临床拟诊为颈部血管狭窄的患者接受了多层螺旋CT血管造影(MD-CTA)检查。根据颈动脉有无AS斑块分为病例组和对照组。分析斑块的类型并测量邻近血管壁的强化程度,评价管壁强化特征与斑块稳定性之间的关系。结果病例组102例,共检出斑块145处,43例发生在双侧,59例发生在单侧。其中富含脂质的斑块16处,纤维化斑块34处,钙化斑块95处。相应的血管壁强化程度:富含脂质斑块为(33.63±7.02)HU,纤维化斑块为(25.21±7.54)HU,钙化斑块为(22.67±4.08)HU。而110例对照组血管壁强化程度为(26.45±6.47)HU。统计学分析显示富含脂质斑块组与对照组之间差异有统计学意义(t=4.11,P=0.0001);纤维斑块组和对照组之间差异无统计学意义(t=0.94,P=0.345);钙化斑块组则明显低于对照组(t=5.07,P<0.05)。富含脂质斑块的强化程度与管壁强化程度之间存在显著性相关(r=0.89,P<0.01)。结论AS血管壁强化程度与斑块的稳定性之间存在相关性,血管壁强化程度越高提示斑块稳定性越差。     

基于VW-MRI的颅内动脉粥样硬化斑块与胚胎型大脑后动脉的相关性研究

目的:基于磁共振血管壁成像(VW-MRI)技术研究颅内动脉粥样硬化斑块与胚胎型大脑后动脉(FTP)的相关性。方法:搜集2018年10月-2022年4月在东南大学附属中大医院行VW-MRI检查的所有患者的病例资料。将有动脉粥样硬化斑块的患者分为FTP组(n=40)和非FTP组(n=67)。比较两组大脑中动脉和椎基底动脉斑块分布特点及血管的狭窄程度、重构指数和偏心指数。结果：共纳入107名患者,FTP组大脑中动脉斑块较非FTP组更好发于血管的背侧壁及上壁(37.5%vs. 16.42%),更容易发生正性重构(1.071±0.267 vs. 0.877±0.232),两组差异有统计学意义(P<0.05)。调整混杂因素后,重构指数与FTP仍然具有相关性(95%CI:1.433～687.143;P=0.029)。两组患者椎基底动脉斑块分布(17.5%vs. 8.96%,10%vs. 11.94%,20%vs. 17.91%)及血管特征(重构指数：1.095±0.347 vs. 0.982±0.247;偏心指数：0.539±1.622 vs. 0.551±0.167)差异无统计学意义(P&g...     

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

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。     

粥样硬化性大脑中动脉的高分辨率MRI成像与脑梗死的血管危险因素研究

目的应用高分辨率MRI成像(HRMRI)观察粥样硬化性大脑中动脉(MCA)的管壁结构,并分析脑梗死的血管危险因素。方法将38例MCA供血区脑梗死或短暂性脑缺血发作(TIA)患者分为梗死组与TIA组,行HRMRI检查,并寻找与脑梗死风险相关的血管危险因素。结果脑梗死组、TIA组两者比较,MCA粥样硬化斑块、斑块稳定性的差异有统计学意义。MCA管腔内存在粥样硬化斑块是脑卒中的血管危险因素。结论 HRMRI能清楚显示动脉粥样硬化性MCA的管壁,对于脑梗死发生风险的评估具有优势。     

高分辨率MRI在大脑中动脉粥样硬化斑块药物治疗随访中的应用

目的 探讨3.0 T高分辨率磁共振(HR-MRI)在大脑中动脉(MCA)斑块所致缺血性脑卒中急性期及非急性期药物治疗随访中的应用价值。方法 前瞻性纳入海军军医大学附属长海医院神经内科及脑外科2012年10月至2015年10月,因MCA粥样硬化狭窄致缺血性脑卒中住院并行HR-MRI管壁成像检查患者,根据患者最近一次症状到HR-MRI检查时间将患者分为急性卒中组与非急性卒中组,所有患者均知情同意接受抗血小板药物及强化降脂治疗,并进行HR-MRI随访复查。HR-MRI扫描序列包括T2WI、T1WI、增强T1WI,同时行常规头颅T2WI、DWI扫描,将治疗前后的HR-MRI图像数据进行对比分析,采用配对样本t检验比较各组责任血管管腔狭窄率、斑块强化率、斑块体积及斑块负荷变化差异及患者美国国立卫生研究院卒中量表(NIHSS)评分、血生化指标变化差异;采用χ2检验对比急性卒中组及非急性卒中组患者脑缺血事件复发差异。结果 本研究共纳入31例责任血管为MCA的急性卒中患者,20例非急性卒中患者。急性卒中组平均随访时间(671.71± 522.86)d,药物治疗后管腔狭窄率(P=0.039)、斑块强化率(P<0.001)、斑块体积(P=0.024)、斑块负荷(P=0.031)均较基线明显好转,神经系统功能NIHSS评分(P<0.001)较基线明显改善,12例随访后进行血脂检查的患者总胆固醇(TC)(P=0.011)、低密度脂蛋白胆固醇(LDL-C)(P=0.047)较基线明显降低。非急性卒中组患者平均随访时间为(695.35±555.90)d,随访后HR-MRI图像斑块变化:管腔狭窄率、斑块体积、斑块负荷均较基线稍减小,斑块强化率稍减低,但差异无统计学意义(P>0.05),神经系统功能NIHSS评分较基线变化不明显(P>0.05),7例随访后进行血脂检查患者TC、甘油三酯(TG)、LDL-C变化较基线无明显变化(P>0.05),但高密度脂蛋白胆固醇(HDL-C)较基线升高(P=0.02)。随访期间两组患者颅脑DWI图像均未发现复发新鲜脑梗死灶,急性卒中组患者短暂性脑缺血发作(TIA)复发6例,非急性卒中组患者TIA复发5例,两组TIA复发差异无统计学意义(χ2=0.229,P=0.632)。结论 HR-MRI可作为MCA粥样硬化斑块药物治疗随访的重要评估方法,急性期缺血性脑卒中患者经抗血小板及强化降脂治疗后MCA责任斑块体积及斑块负荷减小、斑块强化减低,而非急性期患者斑块治疗后变化不显著。     

双低剂量CTA评估颅内动脉粥样斑块稳定性的可行性研究

目的探讨双低剂量CT血管成像(CTA)评估颅内动脉粥样斑块稳定性的可行性。方法选取2015年1月—2016年3月期间于神经内科住院的表现有缺血性脑卒中(CIS)症状的病人42例,其中男29例,女13例,平均年龄(62.3±7.69)岁。将病人随机分为双低剂量组和常规剂量组,每组21例。两组管电压、碘对比剂剂量分别为80 k V、50 m L和120 k V、100 m L。对2组病人分别进行CTA检查,并进行相应后处理以显示颅内动脉斑块。采用t检验对比分析2组影像噪声、血管强化程度、影像质量评分及X线辐射剂量的差异,采用χ~2检验比较2组间斑块检出率的差异。结果双低剂量组的噪声显著高于常规剂量组(P0.05),两组间CNR及SNR差异均无统计学意义(均P0.05)。低管电压组大脑中动脉M1段及椎基底动脉监测点的CT值均高于常规管电压组(均P0.05)。双低剂量组和常规剂量组的影像质量评分均显示良好(均2分),两组间各种影像质量评分差异均无统计学意义(P0.05)。两组斑块检出率差异无统计学意义(P0.05)。双低剂量组的CT容积剂量指数、剂量长度乘积和有效辐射剂量均低于常规剂量组(均P0.05)。结论双低剂量组CTA检查能清楚显示颅内动脉粥样斑块形态及成分,可对其稳定性做出较精确的判断,并能有效降低X线对人体的电离辐射剂量及碘对比剂的肾毒性。双低剂量CTA评估颅内动脉粥样斑块稳定性可行,具有临床应用价值。     

颅内动脉粥样硬化斑块、软脑膜侧支循环与脑血流低灌注的关系：多模态MRI分析

目的:利用三维快速自旋回波和超长回波链采集序列(3D-CUBE)、TOF-MRA及三维动脉自旋标记(3D-ASL)灌注成像等多模态磁共振技术探讨颅内动脉粥样硬化斑块特征、软脑膜侧支与脑灌注之间的关系。方法:将72例症状性大脑中动脉狭窄患者纳入本研究。利用三维动脉自旋标记(3D-ASL)成像技术获得所有患者的脑血流量(CBF)值,根据CBF值将患者分为正常组(23例)和低灌注组(49例)。在3D-CUBE序列上测量大脑中动脉(MCA)狭窄段的管腔狭窄程度,分析和测量责任斑块的特征(包括分布、长度和斑块强化程度),在TOF-MRA原始图像上评估软脑膜侧支循环情况(MCA狭窄侧侧支血管较对侧减少<50%定义为侧支循环差,≥50%则定义为侧支循环良好)。先使用单因素分析两组患者在管腔狭窄程度、斑块特征及软膜侧支之间的差异,再将有统计学差异的变量纳入二元logistic回归模型,最后绘制ROC来评估单变量和组合变量预测供血区脑组织血流低灌注的效能。采用CBF结合阿尔伯塔省卒中项目早期CT评分方法(CBF-ASPECTS)评估脑灌注减低的范围,应用Mann-Whitney U检验评估斑块强化...     

症状性颅内动脉狭窄介入治疗前的影像评估

目的 探讨症状性颅内动脉狭窄介入治疗前影像评估对介入治疗适应证选择的指导价值.方法 26例颅内动脉狭窄患者,介入治疗前全部行DSA、高分辨率MRI斑块成像、CT或MR灌注成像,分别对脑供血动脉、动脉狭窄程度和斑块性质及成分、脑血流灌注情况等进行评价.对动脉粥样硬化性狭窄的患者,根据高分辨MRI表现分析斑块性质,对不稳定性斑块患者行介入治疗;而对动脉炎性狭窄的患者则采用药物治疗.随访观察有无再发缺血性脑卒中事件.结果 18例患者MRI表现为血管偏心狭窄、病灶轻度强化或不强化,DSA表现为Mori B型或C型病变,判断狭窄由动脉粥样硬化斑块引起.这18例中13例为不稳定斑块;1例为稳定斑块伴灌注失代偿,给予颅内支架成形术;其余4例稳定斑块引起狭窄患者采用药物治疗.8例狭窄由动脉炎引起,MRI显示狭窄病变处内膜向心性增厚和环形强化,采取内科保守治疗.本组患者随访1.0～8.0个月,中位时间6.0个月,平均(5.2±3.1)个月,未再出现狭窄病变相关性短暂性脑缺血发作(TIA)或脑卒中.结论 症状性颅内动脉狭窄患者治疗前进行综合影像评估,对于指导临床制定治疗方案具有重要价值.     

颈动脉增强对评价颈动脉斑块稳定性的作用

目的:通过分析颈动脉粥样硬化(AS)血管壁的强化特征,评价血管壁强化程度与斑块稳定性之间的关系.方法:148例临床疑为颈部血管狭窄的患者中61例行CTA、87例行CE-MRA检查,分析斑块的类型并测量邻近血管壁的强化程度以及管腔狭窄程度,评价管壁强化特征与斑块稳定性之间的关系.CTA组部分患者与DSA对照.结果:CTA组:狭窄血管74支,轻度狭窄34支,中度狭窄24支,重度狭窄19支,3支完全闭塞;软斑块32块,硬斑块25块,溃疡斑6块,软斑块处血管壁强化明显高于硬斑块,部分患者与DSA比较,二种检查方法对血管狭窄的显示无显著性差异.CE-MRA组:狭窄血管79支,轻度狭窄28支,中度狭窄33支,重度狭窄13支,5支完全闭塞;软斑块28块,硬斑块49块,血栓2块,软斑块处血管壁强化明显高于硬斑块.结论:CTA和CE-MRA在评价颈动脉粥样硬化斑块的稳定性方面各有优势,能够为临床预测缺血性脑卒中提供非常可靠准确的信息.     

Gadolinium Enhancement of Atherosclerotic Plaque in the Middle Cerebral Artery: Relation to Symptoms and Degree of Stenosis

BACKGROUND AND PURPOSE:High-resolution MR imaging can depict intracranial arterial atherosclerotic plaques. Our aim was to evaluate the relationship between the degree of enhancement of MCA plaques on contrast-enhanced high-resolution MR imaging and ischemic stroke and stenosis severity.MATERIALS AND METHODS:This study enrolled 36 patients diagnosed with moderate-to-severe atherosclerotic MCA stenosis. A contrast-enhanced T1-weighted volume isotropic turbo spin-echo acquisition sequence was acquired for assessing plaque enhancement. Plaque-to-CSF contrast ratio was calculated after the signal intensity of plaques at the stenotic segment was measured. Univariate comparison and multivariate logistic regression analyses were performed for symptomatic and asymptomatic groups to assess the relationship between symptomatic stenosis and independent variables, including plaque-to-CSF contrast ratio, degree of stenosis, and clinical risk factors. Plaque-to-CSF contrast ratio was compared between the moderate and severe stenosis groups.RESULTS:Twenty-one patients had symptomatic MCA stenosis, and 15 had asymptomatic stenosis. The plaque-to-CSF contrast ratio was significantly higher in the symptomatic group than in the asymptomatic group (63.6 ± 10.6% versus 54.1 ± 13.5%, respectively; P < .05). The degree of stenosis also differed significantly between the 2 groups (P < .05). Multivariate analysis revealed that the degree of stenosis was the only independent predictor of ischemic stroke symptoms. The plaque-to-CSF contrast ratio of severe stenosis was significantly higher than that of moderate stenosis (66.8 ± 8.7% versus 55.9 ± 12.8%, respectively; P < .05).CONCLUSIONS:Plaque enhancement was significantly higher in patients with symptomatic plaques and may have been affected by the degree of stenosis. A difference in plaque enhancement according to the degree of stenosis has implications for understanding the development of intracranial atherosclerotic plaques.

Intracranial atherosclerotic disease (ICAD) is now considered the most common cause of ischemic stroke worldwide.^1,2 It is a challenge for many clinicians to assess vulnerable regions of intracranial artery stenosis by using in vivo methods. As a result, there has been a recent increase in interest in techniques to depict the state of the intracranial artery wall by using high-resolution MR imaging (HR-MRI) with a high magnetic field.Inflammation increases vulnerability to plaque rupture by facilitating neovascularization within the plaque and increasing endothelial permeability. Strong contrast enhancement of arterial plaques on MR imaging suggests the presence of a vascular supply and increased endothelial permeability, which facilitate the entry of contrast agents from the blood plasma.^3–6 Several studies have shown that gadolinium (Gd) enhancement of extracranial carotid plaques on MR imaging is associated with plaque neovascularization or increased levels of serum inflammatory markers such as C-reactive protein.^7–10 An association between carotid plaque enhancement and clinical symptoms has been observed in several recent investigations by using Gd-enhanced MR imaging.^9,11In contrast to the numerous investigations that have been performed on the carotid artery, only a few studies performed on a small number of patients have focused on the clinical significance of Gd enhancement of plaques in the setting of ICAD.^12–14 These studies identified a significant association between plaque enhancement on ICAD and ischemic events. However, there is some debate about whether contrast enhancement is a good predictor of intracranial stenosis in ischemic stroke. Klein et al¹⁵ expressed doubt about the relationship between plaque enhancement and stroke because they found stationary enhancement of basilar plaques regardless of the time elapsed after an acute event.Several factors are known to be related to ischemic stroke in the territory of the stenotic segment.^16,17 In particular, the severity of stenosis is a strong predictor of subsequent stroke in the territory of the symptomatic stenotic artery. To assess whether Gd enhancement of plaques at the stenotic segment is valuable as a predictor of ischemic stroke, an unbiased assessment of the influence of other independent factors, including the degree of stenosis, should be undertaken. Thus, the purpose of this study was to evaluate whether Gd enhancement of plaques in ICAD is associated with clinical symptoms, independent of other predictive factors for ischemic stroke risk.     

高分辨力MR成像检查大脑中动脉粥样硬化斑块的研究进展

颅内动脉粥样硬化在亚洲是缺血性卒中的主要病因,其在我国的脑卒中和短暂性脑缺血发作中也有较高发生率。高分辨力MR成像作为目前唯一可以在体进行的血管壁成像的无创技术,临床应用越来越广泛,尤其是对大脑中动脉的研究。高分辨力MR成像能评估动脉管腔的狭窄程度、斑块分布、斑块信号特点、管壁重构方式等,为临床治疗提供更多的有用信息。现就近年来高分辨力MR成像检查颅内大脑中动脉粥样硬化斑块的研究进展进行综述。     

High-Resolution Intracranial Vessel Wall MRI Findings Among Different Middle Cerebral Artery Territory Infarction Types

ObjectiveIntracranial atherosclerotic stroke occurs through various mechanisms, mainly by artery-to-artery embolism (AA) or branch occlusive disease (BOD). This study evaluated the spatial relationship between middle cerebral artery (MCA) plaques and perforating arteries among different MCA territory infarction types using vessel wall magnetic resonance imaging (VW-MRI).Materials and MethodsWe retrospectively enrolled patients with acute MCA infarction who underwent VW-MRI. Thirty-four patients were divided into three groups according to infarction pattern: 1) BOD, 2) both BOD and AA (BOD-AA), and 3) AA. To determine the factors related to BOD, the BOD and BOD-AA groups were combined into one group (with striatocapsular infarction [BOD+]) and compared with the AA group. To determine the factors related to AA, the BOD-AA and AA groups were combined into another group (with cortical infarction [AA+]) and compared with the BOD group. Plaque morphology and the spatial relationship between the perforating artery orifice and plaque were evaluated both quantitatively and qualitatively.ResultsThe plaque margin in the BOD+ group was closer to the perforating artery orifice than that in the AA group (p = 0.011), with less enhancing plaque (p = 0.030). In the BOD group, plaques were mainly located on the dorsal (41.2%) and superior (41.2%) sides where the perforating arteries mainly arose. No patient in the AA group had overlapping plaques with perforating arteries at the cross-section where the perforator arose. Perforating arteries associated with culprit plaques were most frequently located in the middle two-thirds of the M1 segment (41.4%). The AA+ group had more stenosis (%) than the BOD group (39.73 ± 24.52 vs. 14.42 ± 20.96; p = 0.003).ConclusionThe spatial relationship between the perforating artery orifice and plaque varied among different types of MCA territory infarctions. In patients with BOD, the plaque margin was closer and blocked the perforating artery orifice, and stenosis degree and enhancement were less than those in patients with AA.     

Fly through ultrasound imaging in assessment of carotid atherosclerosis: a pictorial essay

To assess fly through ultrasound imaging (FTUS) in evaluation of carotid artery atherosclerosis, we prospectively performed conventional sonography and FTUS of the carotid artery on 66 patients with suspicion for atherosclerosis. Characteristics of arterial intima, atherosclerotic plaque, luminal narrowing, and carotid stent graft displayed on FTUS were compared with that on conventional sonography. On FTUS, normal carotid artery wall was smooth in appearance, mild carotid atherosclerosis appeared focal arterial wall irregularity and small plaque formation, arterial luminal reduction resulted from progressive artery plaques, and carotid stent had irregular inner lumen and tight fit against the arterial wall. A total of 38 plaques were detected by conventional sonography, while 48 plaques were depicted by FTUS in 25 patients. Using magnetic resonance angiography as a reference standard, 17 cases with >50% and 3 cases with < 50% luminal reduction measured on FTUS. However, all those 20 cases were measured with >50% luminal reduction on conventional sonography. Compared with conventional sonography, FTUS can dynamically display intraluminal structure on real-time three-dimensional imaging morphologically to improve the accuracy in detecting atherosclerotic plaque and assessing luminal narrowing in the carotid artery.     

Atherosclerotic plaque features and distribution in bilateral carotid arteries of asymptomatic elderly population: A 3D multicontrast MR vessel wall imaging study

PurposeThis study sought to investigate the characteristics of morphology, compositions and distribution of carotid atherosclerotic plaques in asymptomatic elderly population using three dimensional (3D) multicontrast magnetic resonance vessel wall imaging.Materials and methods146 asymptomatic elderly subjects (≥ 60 years) were recruited and underwent 3D multicontrast MR vessel wall imaging for bilateral carotid arteries on a 3.0T MR scanner. The presence of carotid atherosclerotic plaque was determined and the stenosis was measured. The characteristics of plaque morphology and compositions were evaluated and compared among distal internal carotid artery (D-ICA), proximal-ICA (P-ICA), carotid bulb (CB), distal common carotid artery (D-CCA) and proximal-CCA (P-CCA).ResultsOf all recruited 140 subjects (72.1 ± 5.7 years, 63 males), 87 (62.1%) had carotid plaques, 17 (12.1%) had high-risk plaques and 51 (36.4%) had multiple plaques. Of all 280 carotid arteries, only 16 (5.7%) had luminal stenosis (21.1% ± 11.4%). Among carotid arteries without luminal stenosis, the prevalence of plaque and high-risk plaques was 43.2% and 8.3%, respectively. Carotid plaques were mostly found in CB segment (33.9%), followed by P-ICA (13.6%), P-CCA (11.1%), D-CCA (4.6%) and D-ICA (3.6%). Age was independently associated with presence of multiple carotid plaques (odds ratio, 1.835; 95% confidence interval, 1.196–2.815; P = 0.005).ConclusionCarotid artery atherosclerotic plaques are prevalent and a substantial number of high-risk plaques can be found in the asymptomatic elderly subjects. Longitudinal studies are warranted to investigate the risk of having ischemic stroke for asymptomatic elderly individuals with carotid artery high risk plaques.     

DSCTA对颈动脉斑块特征与急性缺血性脑卒中的相关性研究

目的 探讨双源CT血管成像（DSCTA）对颈动脉斑块的诊断价值,评估颈动脉狭窄<50%的斑块特征与急性缺血性脑卒中的关系。方法 选取符合纳入标准患者64例,回顾性分析颈动脉分叉处斑块特征,急性脑卒中侧为实验组,无急性脑卒中侧为对照组。分析内容包括斑块类型、斑块表面形态、钙化分布、钙化数目,对两组颈动脉斑块特征进行统计学分析。结果 实验组颈动脉斑块较对照组更容易出现以下特征且差异有统计学意义,包括非钙化性和混合性斑块出现率更高（Z=-2.39,P=0.02）,斑块表面不规则和溃疡出现率更高（Z=-6.04,P<0.01）,浅层钙化（Z=-2.06,P=0.04）和多发钙化出现率更高（Z=-2.52,P=0.01）。结论 DSCTA可更好的显示斑块特征,颈动脉非钙化性和混合性斑块、斑块表面不规则或溃疡形成、浅层钙化和多发钙化可能为急性缺血性脑卒中的危险因素。