高分辨率磁共振血管壁成像对大脑中动脉粥样硬化斑块与豆纹动脉血管特征分析的运用研究

目的:解读高分辨率磁共振(high resolution magnetic resonance imaging,HR-MRI)血管壁成像评估大脑中动脉(middle cerebral artery,MCA)粥样硬化斑块的强化程度及粥样硬化斑块与豆纹动脉血管特征的关系.方法:采集新疆医科大学第二附属医院2020年4月—2...     

不同年龄大鼠大脑中动脉弹性纤维的变化

背景：大脑中动脉弹性纤维的变化与老年性脑血管疾病密切相关。目的：观察不同年龄大鼠大脑中动脉弹性纤维的变化。设计：以实验动物为观察对象的对比实验。单位：解放军第三军医大学解剖教研室和中心实验室。材料：健康Wistar大鼠36只，雌雄不拘，体质量200～280g，由重庆第三军医大学动物所提供[生产合格证号：SCXX(军)2002—007]。干预：运用光镜、电镜和图像分析仪对不同年龄的大鼠大脑中动脉弹性纤维进行系统研究。主要观察指标：①主要结局：各年龄大鼠大脑中动脉内弹性膜的变化。②次要结局：透射电镜下观察内弹性膜超微结构变化。结果：随着年龄增加，内弹性膜折叠的幅度和数量均减小，弹性纤维含量显著减少(P&;lt;0．01)，胶原纤维与弹性纤维的比值显著增加(P&;lt;0．01)；&;gt;24月龄组内弹性膜变薄，不均质，内皮细胞和平滑肌细胞向内弹性膜穿过，内弹性膜内出现脂质，并有分层、断裂现象。结论：弹性纤维的变化可能与年老后易发生脑血管疾病有关。     

冠状动脉粥样硬化与外周动脉粥样硬化的相关性的研究进展

动脉粥样硬化是动脉内膜的脂质、复合碳水化合物、血液成分的沉积以及平滑肌和胶原纤维增生，伴有不同程度的坏死及钙化的一种病变。以内膜增厚及退行性改变为特征。动脉粥样硬化主要侵及较大的弹力动脉和中等的平滑肌血管，主要累及冠状动脉、脑动脉、主动脉及其主要的分...     

高分辨力超声观测急性同型半胱氨酸血症导致兔血管内皮功能损伤

目的 探讨急性高同型半胱氨酸血症(HHcy)导致内皮功能损伤时，兔髂外动脉血管内皮细胞、平滑肌细胞是否出现超微结构的改变。方法 将兔随机分为两组，每组9只，分别灌服5．0g／kg体质量的L-蛋氨酸(M组)和等量的自来水(N组)，然后于0、4、8、12、24h，利用高分辨力超声检测其内皮依赖性舒张功能(EDD)、内皮非依赖性舒张功能(EID)．并利用透射电镜观察24h后兔髂外动脉超微结构的改变。结果 ①急性HHcy时，M组兔髂外动脉的EDD较对照组显著降低，且呈明显的时间依赖性；而EID无明显的改变；②透射电镜下，兔髂外动脉内皮细胞均出现脱落，其线粒体肿胀，内质网扩张，内弹力板断裂，平滑肌细胞通过断裂的内弹力板向内皮下侵入，平滑肌细胞的线粒体也有不同程度的肿胀。结论 利用高分辨力超声可准确观测急性HHcy导致的EDD损伤，而兔血管内皮细胞、平滑肌细胞以及内弹力板的超微结构的破坏为其提供了形态学的证据。     

彩色多普勒对新生儿脑水肿时豆纹动脉的观察与分析

目的探讨和研究彩色多普勒超声诊断新生儿窒息后引发脑水肿时大脑终末动脉-豆纹动脉的血流灌注情况。方法应用彩色多普勒技术对23例正常足月新生儿和36例足月脑水肿儿进行二维图像和豆纹动脉血流检测,时间限于出生后3d以内。结果豆纹动脉显示率两组均为100%,选择切面为第三脑室层面冠状面和旁正中矢状面,正常组收缩期峰值流速为(12.70±2.19)cm/s,阻力指数0.47±0.04,彩色血流显示为以红色为主的连续性多条细束状血流信号。脑水肿组86%脑血流峰值流速降低,14%增高或正常,平均为(9.05±4.45)cm/s,组间的差异具有显著意义(P<0.001)。阻力指数两组间差异无显著意义(P>0.05)。结论豆纹动脉作为脑组织中的终末小动脉直接反映脑血流动力学变化和大脑中央区的血流灌注情况,对评价脑水肿的程度和指导临床治疗帮助较大。     

高分辨率磁共振血管壁成像对大脑中动脉粥样硬化斑块与豆纹动脉血管特征分析的应用研究

目的探讨高分辨率磁共振成像(high-resolution magnetic resonance imaging,HR-MRI)血管壁成像技术对大脑中动脉(middlecerebralartery,MCA)粥样硬化斑块强化程度及血管重塑方面与豆纹动脉数量及深度之间的联系。材料与方法收集新疆医科大学第二附属医院40例有症状组患者与40例无症状组患者参加该研究,对所有受试者行HR-MRI 3D-T1WI-VISTA序列成像。受试者高分辨血管成像数据传至后处理工作站,应用Philips Intellispace portal软件对大脑中动脉斑块强化指数及管腔重构指数与豆纹动脉血管数量及深度进行统计。采用SPSS 25.0软件对两组受试者大脑中动脉斑块强化指数及管腔重构指数与豆纹动脉的深度及数目进行统计学分析。结果有症状组患者组与无症状组患者组相比,有症状组患者组MCA粥样斑块有更高的增强指数(P0.05)且豆纹动脉长度明显短于无症状组(P0.05)。有症状组患者组与无症状组患者组MCA管腔重塑指数与豆纹动脉数量差异均无统计学意义(P0.05)。结论有症状组患者组与无症状组患者组MCA粥样斑块的强化程度与豆纹动脉深度存在一定差异,高分辨磁共振血管壁成像对MCA粥样斑块评估具有临床价值。     

胎儿脑动脉分叉部构筑发育特征与脑动脉瘤病因假说的验证

目的：探讨人类胚胎脑动脉分叉部弹力纤维和中层平滑肌细胞(smooth muscle cell，SMC)的构筑发育过程及特点，以助对脑动脉瘤病因假说的理解和验证。方法：收集胎龄12—28周人类胚胎共17例，每1个周龄取1例，男女不限。对胎脑willis环周围的动脉分叉部行不同方向组织切片，观察弹力纤维和中层SMC的构筑发育过程。结果：胎脑Willis环周各动脉弹力纤维在l.5-12．6层之间，弹力纤维在同一切片有紊乱和逐渐减少现象，内弹力层第19周发育完整；中层SMC在1．1—9．0层之间，70．6％的胎脑动脉个别分叉部发现中层SMC缺陷。所取标本的30．3％发现中层SMC缺陷。结论：胎脑动脉内弹力纤维和中层SMC随胎龄增长而增多，内弹力层于第13—19周出现并发育成熟，脑动脉分叉部存在先天性SMC缺陷、弹力纤维紊乱和逐渐减少现象，有助于对脑动脉瘤病因假说的理解和验证。     

易卒中型自发性高血压大鼠大脑中动脉血管平滑肌细胞膜电位的特性

背景：动脉血管平滑肌细胞膜电位的微小变化就可以导致张力的显著性改变，膜去极化与高血压形成有密切关系。目的：研究易卒中型自发性高血压大鼠大脑中动脉平滑肌细胞的静息膜电位（Em）及其对血管活性物质KCl、去甲肾上腺素的反应性。设计：对照分析动物实验。单位：山东省医学科学院药物研究所。材料：雄性卒中型自发性高血压大鼠18只和雄性Wistar大鼠26只。方法：①两组大鼠经乌拉坦（1g／kg）腹腔注射麻醉，迅速取出大脑，剥离出大脑中动脉，应用细胞内微电极记录血管平滑肌细胞膜电位。（多分别观察不同浓度的KCl（10，20，50mmol／L），去甲肾上腺素（10^-710^-6，10^-5mol／L）对血管平滑肌细胞膜电位的影响。主要观察指标：①两组大鼠血管平滑肌细胞膜电位。②不同浓度的KCl和去甲肾上腺素对血管平滑肌细胞膜电位的影响。结果：①卒中型自发性高血压大鼠膜电位明显低于Wistar大鼠[（-48．2&;#177;3．1），（-64．4&;#177;4．3）mv]。②KCl（10，20，50mmol／L）和去甲肾上腺素（10^-7，10^-6，10^-5mol／L）均引起大脑中动脉膜电位去极化，且皆呈剂量依赖式特点；与Wistar大鼠比较，卒中型自发性高血压大鼠的大脑中动脉反应性明显增强。结论：卒中型自发性高血压大鼠大脑中动脉血管平滑肌细胞膜电位较低，对KCl和去甲肾上腺素的反应性明显高于Wistar大鼠。     

症状性大脑中动脉狭窄的脑梗死模式观察

目的：观察症状性动脉粥样硬化性大脑中动脉狭窄患者的脑梗死模式和分布，探讨动脉粥样硬化性大脑中动脉狭窄导致脑梗死的病理生理机制。方法：回顾性分析2004-06／2005-08在北京天坛医院脑血管病抢救治疗中心治疗的50例脑血管造影证实的症状性大脑中动脉狭窄患者的MRI影像学资料，所有患者狭窄率〉50％，不伴有同侧颈内动脉狭窄或闭塞，具有≥1个的动脉粥样硬化危险因素，对其脑梗死模式进行分类观察。结果：50例大脑中动脉狭窄患者的神经影像学资料分析显示，皮质下梗死最常见，其中深穿支梗死44％、内交界区梗死42％；皮质支梗死和区域性梗死各占6％和2％；散发皮质小梗死14％；外交界区梗死中前交界区梗死12％、后交界区梗死24％。结论：动脉粥样硬化性大脑中动脉狭窄可以表现为多种脑梗死模式，提示大脑中动脉狭窄导致脑梗死不同的病理生理机制。     

新生儿豆纹动脉多普勒检测评价脑血流灌注

目的：研究应用彩色多普勒超声检测新生儿豆纹动脉血流的可靠性及其评价脑血液灌注的临床意义。方法：应用彩色多普勒超声检测37例正常足月新生儿和28例早产儿豆纹动脉血流参数：S、D、S／D和RI,将大脑中央区血流灌注分为0－Ⅲ级,比较各组的脑血流灌注。结果：正常足月儿出生后10天内豆纹动脉峰值流速、平均流速较低,60％脑血流灌注呈轻度降低。出生10天后血流灌注正常,与早产儿相比差异有高度显著性（P＜0．01）。早产和脑血流速度极低,脑血流灌注降低中度46％、重度10％,与足月儿差异有显著意义（P＜0．01）;而S／D与RI高于正常足月儿（P＞0．05）。结论：新生儿豆纹动脉血流多普勒检测准确易行,可反映脑血流动力学变化和大脑中央区血流灌注水平,有助于脑损伤的判断与治疗。     

不同年龄大鼠大脑中动脉弹性纤维的变化

背景大脑中动脉弹性纤维的变化与老年性脑血管疾病密切相关.目的观察不同年龄大鼠大脑中动脉弹性纤维的变化.设计以实验动物为观察对象的对比实验.单位解放军第三军医大学解剖教研室和中心实验室.材料健康Wistar大鼠36只,雌雄不拘,体质量200～280 g,由重庆第三军医大学动物所提供[生产合格证号SCXX(军)2002-007].干预运用光镜、电镜和图像分析仪对不同年龄的大鼠大脑中动脉弹性纤维进行系统研究.主要观察指标①主要结局各年龄大鼠大脑中动脉内弹性膜的变化.②次要结局透射电镜下观察内弹性膜超微结构变化.结果随着年龄增加,内弹性膜折叠的幅度和数量均减小,弹性纤维含量显著减少(P＜0.01),胶原纤维与弹性纤维的比值显著增加(P＜0.01);＞24月龄组内弹性膜变薄,不均质,内皮细胞和平滑肌细胞向内弹性膜穿过,内弹性膜内出现脂质,并有分层、断裂现象.结论弹性纤维的变化可能与年老后易发生脑血管疾病有关.     

线栓法制作兔大脑中动脉闭塞脑缺血模型

目的:探讨兔颈内动脉系统的结构和变异及采用线栓法制作兔大脑中动脉闭塞脑缺血模型的可行性。方法:新西兰白兔40只,20只制作脑血管模型,20只制作大脑中动脉闭塞脑缺血模型。0.8号渔线经颈内动脉插至大脑中动脉起始部,观察颅内压、肛温、中心静脉压和股动脉压,48 h后行头颅MRI,过量麻醉处死,取脑进行TTC染色和HE染色。结果:兔颈内动脉起始段与大脑中动脉起始段间距4.2-4.8 cm,多数(85%)无分支,少数(15%)在颈内动脉入颅前向后分出供应耳后部的分支。线栓大脑中动脉后,兔的血压、颅内压逐渐升高,头颅MRI和TTC染色均可见梗死灶,其大小、部位基本一致。结论:线栓法制作兔大脑中动脉闭塞脑缺血模型操作简单,创伤小,制作的模型稳定,成功率高。     

Segmentation of wall and plaque in in vitro vascular MR images

Atherosclerosis leads to heart attack and stroke, which are major killers in the western world. These cardiovascular events frequently result from local rupture of vulnerable atherosclerotic plaque. Non-invasive assessment of plaque vulnerability would dramatically change the way in which atherosclerotic disease is diagnosed, monitored, and treated. In this paper, we report a computerized method for segmentation of arterial wall layers and plaque from high-resolution volumetric MR images. The method uses dynamic programming to detect optimal borders in each MRI frame. The accuracy of the results was tested in 62 T1-weighted MR images from six vessel specimens in comparison to borders manually determined by an expert observer. The mean signed border positioning errors for the lumen, internal elastic lamina, and external elastic lamina borders were –0.1 ± 0.1, 0.0 ± 0.1, and –0.1 ± 0.1 mm, respectively. The presented wall layer segmentation approach is one of the first steps towards non-invasive assessment of plaque vulnerability in atherosclerotic subjects.     

Backscatter directivity and integrated backscatter power of arterial tissue

A 27 MHz transducer, mounted on an ultrasonic microscope, was used to quantify the dependence of backscatter power on the angle of incidence of arterial vessels. Due to variations in the angle of incidence significant variations in backscatter power were found in the intima, the muscular and elastic media, the adventitia and the external elastic lamina. The muscular and the elastic media show anisotropic behaviour in their angle dependence, i.e. the extent of the angle dependence depends on the direction of angle variation. This anisotropic nature is probably caused by the dominant orientation of smooth muscle cells or elastin fibers in these tissue layers. Measurements on 13 specimens of the iliac artery showed that each tissue type of the vessel has its own specific angle dependent behaviour. In the future this property might be used for quantitative tissue characterization.     

Disruption of the elastin gene in adult Williams syndrome is accompanied by a paradoxical reduction in arterial stiffness

Although the aetiology of Williams syndrome (WS) is related to elastin gene disruption, its pathogenesis remains unknown, particularly that of vascular lesions. The aim of the present study was to compare the elastic properties of three WS patients with age- and gender-matched normotensive and hypertensive controls. Common carotid arteries of WS patients had a higher distensibility, a thicker intima-media and a lower elastic modulus. Electron microscopy studies of one WS renal artery showed major abnormalities of the elastic fibres, which displayed a reticular structure and a thickening of the internal elastic lamina, whereas the ultrastructure of elastic fibres was normal in a control subadventitial muscular fibrodysplasia. In this WS arterial stenosis, we studied the expression patterns of several major smooth muscle (SM) phenotypic markers using immunofluorescence and used a normal renal artery as a control. In WS, SM-alpha-actin- and myosin-heavy-chain-positive cells contained low amounts of heavy caldesmon, and laminin-beta1 chain was expressed into the basement membranes, indicating a less differentiated phenotype. In conclusion, in WS patients, the carotid artery wall was abnormally distensible and thick, and major ultrastructural abnormalities of elastic fibres were observed in association with smooth muscle cell de-differentiation. These results indicate that the haplo-insufficiency of the elastin gene in WS patients leads to abnormal elastic fibre assembly within the media. Arterial wall hypertrophy found with a primary defect in elastin may represent a major factor responsible for increased distensibility. We suggest that, in WS, the increased proliferative response and the associated de-differentiation process represent two important mechanisms underlying the matrix accumulation and the development of arterial stenosis.     

Neonate Leigh disease: Case report北大核心CSCD

目的 观察MR三维颅内血管解剖成像(3D-IVAS)技术显示大脑中动脉(MCA)的价值。方法 回顾性分析137例接受3D-IVAS及三维时间飞跃法MR血管成像(3D-TOF MRA)检查的患者,共纳入274支MCA,包括动脉粥样硬化组197支、动脉粥样硬化性烟雾综合征组23支、烟雾病组8支及正常组46支;对比3D-IVAS、3D-TOF MRA显示MCA效果评分,于3D-IVAS图像上测量各组MCA起始部血管外径,并进行比较。结果 3D-IVAS显示MCA的效果评分小于3D-TOF MRA(P<0.01)。动脉粥样硬化组、动脉粥样硬化性烟雾综合征组、烟雾病组及正常组MCA外径分别为(2.87±0.56)、(1.99±0.50)、(1.97±0.74)及(2.75±0.43)mm,组间总体差异有统计学意义(F=24.16,P<0.01),且动脉粥样硬化性烟雾综合征组、烟雾病组均小于正常组及动脉粥样硬化组(P均<0.05)。结论 利用3D-IVAS技术可清晰显示大脑中动脉外廓,有助于鉴别诊断相关疾病。     

Bilateral internal carotid artery dissection due to trivial trauma

Internal carotid artery dissection (ICAD) is a known cause of unilateral headache and focal cerebral ischemic symptoms. Other symptoms include oculosympathetic paresis, facial pain, neck pain, subjective carotid bruits, and cranial nerve deficits. Traumatic dissection has an obvious precipitating incident preceding the neurologic or visual symptoms. An ICAD that occurs spontaneously or from trivial trauma usually lacks an obvious incident and thus requires awareness of its possibility for accurate detection and treatment. Dissections arise from a defect in the internal elastic lamina allowing penetration of blood into the arterial wall. Despite its low incidence, ICAD must be considered in young to middle-aged patients who present with headache and transient cerebral or retinal ischemic symptoms. This report describes a patient who had bilateral internal carotid artery dissections following trivial trauma. The etiologies, clinical manifestations, diagnostic modalities, treatment options, and outcomes of ICAD are discussed.     

Detection of stenoses in the anterior circulation using frequency-based transcranial color-coded sonography

Atherosclerotic stenoses of the intracranial vessels are less frequent than those of the extracranial vessels, but they are associated with a considerable annual stroke rate. The aim of the present study was to investigate the usefulness of frequency-based transcranial color-coded sonography (TCCS), transcranial Doppler sonography (TCD) and digital subtraction angiography (DSA) in patients with middle cerebral artery (MCA) and intracranial internal carotid artery (ICA) stenosis. Forty patients presenting with 48 intracranial stenoses of the anterior circulation were involved in the study. The stenoses were detected in the neurovascular laboratory during routine TCD examinations. All patients underwent an additional frequency-based TCCS examination. Both the axial and coronal planes were obtained to allow the exact localization of MCA stenosis and differentiation from intracranial ICA stenosis. Angle-corrected flow velocity measurements were performed if straight vessel compartments were 20 mm or more in length. A total of 18 stenoses (44%) were investigated additionally with DSA. According to the investigation with TCD, 20 (42%) stenoses were low-grade, 12 (25%) were moderate, and the remaining 16 (33%) were severe. Angle-corrected flow velocity measurements obtained with the integrated pulse-wave Doppler device of the TCCS machine were highly correlated (0.912, p < 0.001) with those obtained with TCD. TCCS achieved a reliable differentiation of MCA main stem stenosis vs. intracranial ICA stenosis in 7 patients and vs. MCA branch stenosis in 4 patients, but TCD failed in these two subgroups. The agreement between DSA and TCCS to evaluate semiquantitatively 18 intracranial stenoses resulted in a weighted-kappa value of 0.764. The major clinically relevant advantages of TCCS over TCD in MCA stenosis are its ability to differentiate MCA trunk stenosis from terminal ICA or MCA branch stenosis reliably and to perform angle-corrected flow velocity measurements.     

三维CT血管造影在脑梗死诊断中的应用

目的 探讨三维CT血管造影(3D-CTA)对脑梗死的诊断作用。方法 应用Toshiba Aquilion型多层螺旋CT扫描仪对26例脑梗死病人进行3D-CTA检查，分别对大脑前动脉、大脑中动脉、大脑后动脉和椎-基底动脉系统进行检测并评估。结果 发现大脑中动脉闭塞或狭窄17例，大脑后动脉闭塞或狭窄2例，椎动脉狭窄1例。6例未见血管异常，其中5例为多发性腔隙梗死。全部26例病人中，只见到1例动脉内壁不光滑，未见到斑块、钙化、溃疡及血栓形成。结论 脑梗死的病因可能以栓塞为多见；3D-CTA具有灵活的三维影像后处理功能，能提供脑血管病的多方面信息，是诊断脑梗死的重要工具之一。     

The effect of vasospasm on cerebral perfusion: a colour duplex study of the extra- and intracranial cerebral arteries

To assess whether middle cerebral artery (MCA) vasospasm reduces the flow volume in the corresponding extracranial internal carotid artery (ICA) or global cerebral blood flow volume (CBFV) in subarachnoid haemorrhage (SAH) patients, a colour duplex ultrasound study of the intra- and extracranial cerebral arteries was performed. MCA vasospasm was defined as a time-averaged maximum flow velocity (TAMX) exceeding 120 cm/s. ICA flow volumes and CBFV, were compared in each patient at maximum TAMX recorded in one MCA ("maximum-vasospasm") and when TAMX in the same vessel was closest to mean reference values ("no-vasospasm"). Additionally, the CBFV course during the first 3 weeks after SAH was evaluated longitudinally. Data from age- and gender-matched healthy test persons served as control. In 28 patients with MCA vasospasm, 337 measurements were completed. Global CBFV was significantly reduced starting from day 3 after SAH. ICA flow volumes and CBFV were not different when comparing at "maximum-vasospasm" and "no-vasospasm". Compared with the control group, both were lower at either condition. Thus, in SAH patients, vasospasm even severe, in general does not further diminish ICA flow volumes and global CBFV, which are reduced already before the onset of vasospasm.