缺血性卒中患者颈动脉粥样硬化斑块高分辨磁共振成像研究进展

脑卒中是严重危害人类生命健康的主要疾病之一,而以动脉粥样硬化性病变为病理基础的缺血性卒中为其最常见的临床发病类型。因此,及时识别粥样硬化斑块易损性即显得愈发重要。颈动脉MRI作为一项无创性检查手段,对动脉粥样硬化斑块性质的检测具有独特优势,对显示斑块形态和成分具有较高的敏感性和特异性,可以对粥样硬化斑块破裂的潜在危险进行评价和分层,进而为临床制定有效治疗方案提供影像学诊断依据。     

他汀类药物与颈动脉粥样硬化斑块

卒中,尤其是缺血性卒中的发病率居高不下,颈动脉粥样硬化斑块作为缺血性卒中的重要危险因素,成为近年研究的热点,积极治疗颈动脉粥样硬化斑块成为防治缺血性卒中的重要手段之一。他汀类药物的调脂、稳定及逆转斑块的作用,得到了多项临床试验的肯定,并在临床应用上逐渐推广：下面结合动脉粥样硬化的发病机制,对他汀类药物治疗颈动脉粥样硬化斑块的机制进行综述。     

多血管床动脉粥样硬化斑块与脑血管事件相关性研究进展

脑动脉、冠状动脉及周围动脉的粥样硬化斑块的病理特点及危险因素具有一定差异性。 而单一血管床及多血管床的动脉粥样硬化斑块均对脑血管事件具有一定的预测价值。本文对以上内 容进行综述，旨在更好地理解不同血管床动脉粥样硬化的发病过程、疾病特征及相关风险，为动脉 粥样硬化卒中的病因学诊断、治疗和预防提供参考。     

血流剪切力与颈动脉粥样硬化的关系

颈动脉粥样硬化是导致卒中的重要原因之一。颈动脉粥样斑块好发于颈动脉开口、分叉和弯曲等部位，用全身因素难以解释，提示血液动力学在动脉粥样硬化的形成过程中发挥了重要作用。其中剪切力认为是与动脉粥样硬化发生及斑块破裂最为相关的力学因素。本文对血流剪切力的主要检测方法，血流剪切力对颈动脉粥样硬化的形成、发展的作用及其与斑块性质及斑块破裂的关系进行了综述。     

去乙酰化酶3在人颈动脉粥样硬化斑块中的表达及其临床意义

目的检测人颈动脉粥样硬化斑块组织及正常颈动脉组织中去乙酰化酶3(SIRT3)的表达水平,分析其与颈动脉粥样硬化斑块形成的关系及临床意义。方法利用HE染色、Masson’s trichrome染色及油红O染色对6例颈动脉组织进行粥样硬化斑块分期,利用免疫组化法和Western blot检测不同分期的斑块组织及正常颈动脉组织中SIRT3的蛋白表达差异,利用免疫荧光共定位法观察SIRT3的细胞定位。结果 6例组织分别为2例正常血管组织,2例Ⅰ期动脉粥样硬化组织,2例Ⅳ期动脉粥样硬化斑块组织,Western blot及免疫组化染色显示SIRT3在Ⅳ期颈动脉粥样硬化斑块组织中显著表达,正常血管组织及Ⅰ期粥样硬化血管组织中未见SIRT3表达;免疫荧光共定位染色结果显示,SIRT3在Ⅳ期斑块内的内皮细胞、平滑肌细胞和巨噬细胞内均有显著表达。结论SIRT3在颈动脉粥样硬化Ⅳ期斑块中表达显著增高,可能作为评估粥样硬化稳定性的一个重要指标。     

青中年脑梗死与颈动脉粥样硬化的关系

目的 研究中青年脑梗死与颈动脉粥样硬化的关系.方法 应用彩色多普勒超声仪对中青年脑梗死患者 66 例、36例非脑血管病患者和正常体检者(对照组)行颈部血管超声检查.检测血管壁的厚度和斑块的大小及厚度,观察颈动脉粥样硬化斑块的数目及部位,计算斑块积分及血管狭窄程度.结果 中青年脑梗死患者颈动脉内膜增厚,动脉粥样硬化斑块的发生率明显高于对照组,斑块积分为轻中度的颈动脉粥样硬化,颈动脉血管多为轻中度狭窄.结论 颈动脉粥样硬化与青中年脑梗死关系密切,颈动脉超声检查对脑梗死的发生有极好的预测价值.     

瑞舒伐他汀对急性缺血性卒中患者炎性因子及颈动脉粥样硬化斑块的影响

评价瑞舒伐他汀对缺血性卒中患者血清脂质、炎性因子及颈动脉粥样硬化斑块的影响。共98例急性缺血性卒中伴颈动脉粥样硬化患者应用瑞舒伐他汀10 mg,睡前顿服。连续治疗6个月后分别测定血清超敏C.反应蛋白、肿瘤坏死因子.α及血清脂质变化,对比颈动脉内.中膜厚度,计算颈动脉粥样硬化斑块积分。结果显示,瑞舒伐他汀治疗6个月后患者血清超敏C.反应蛋白、肿瘤坏死因子.α及血清脂质水平下降(P<0.01);颈动脉粥样硬化斑块总数减少、稳定性斑块数目有所增加、颈动脉内.中膜厚度及颈动脉粥样硬化斑块积分下降(P<0.05)。提示瑞舒伐他汀具有抗炎及改善颈动脉粥样硬化斑块程度的作用。     

颈动脉粥样硬化斑块与新生血管的相关性研究进展

缺血性卒中最常见的病因是动脉粥样硬化,颈动脉粥样硬化斑块的破裂可导致卒中事件 的发生。斑块内的复杂结构特征与斑块的易损性相关。斑块内新生血管是斑块发展和不稳定性增加 的危险因素之一。因此,正确认识斑块内新生血管的病因和发病机制,以及与斑块稳定性之间的关 系,有利于早期发现颈动脉粥样硬化并正确评估其稳定程度及破裂风险,对于预防和治疗卒中具有 重要意义。     

彩超诊断脑梗死与颈动脉硬化斑块关系探讨

目的探讨脑梗死与颈动脉粥样硬化斑块之间的关系。方法应用彩色多普勒超声对68例脑梗死患者颈动脉进行检查,并与合并高血压患者颈动脉粥样硬化斑块对比分析。结果 68例脑梗死患者共检出颈动脉粥样硬化斑块54例(79.4%),斑块分布以颈动脉分叉处多见,高龄、高血压及颈动脉粥样硬化斑块的形成与脑梗死密切相关。结论不稳定性斑块脱落是造成脑梗死的重要原因之一。     

阿托伐他汀钙联合降脂通络胶囊治疗动脉粥样硬化型脑梗死的疗效

正动脉粥样硬化是动脉壁中沉积的脂质逐步形成斑块的发展过程,最易受累的部位是颈动脉[1]。颈动脉粥样硬化与脑梗死的发生关系密切,其引起脑梗死的一个重要原因为斑块脱落形成栓子,造成颅内动脉的栓塞。动脉粥样硬化型(arteriosclerosis,AT)是脑卒中新的病因分型的一种,具有颅内外动脉发生粥样硬化的表现,积极有效地治疗颈动脉粥     

磁共振斑块成像与缺血性卒中的相关性研究进展

动脉粥样硬化易损斑块破裂是导致缺血性卒中的主要原因。与组织病理学对照研究证实,
高分辨率磁共振成像可以无创性评价动脉粥样硬化斑块的负荷、成分及其易损性。大量研究显示,
脑血管粥样硬化斑块的磁共振表现特征与缺血性卒中具有明显的相关性。本文将从磁共振斑块成
分特征与缺血性脑血管事件的相关性方面进行综述,为缺血性卒中的病因学诊断和疾病的预防提供
重要依据。     

Molecular imaging of matrix metalloproteinases in atherosclerotic plaques

Ischaemic stroke and myocardial infarction often result from the sudden rupture of an atherosclerotic plaque. The subsequent arterial thrombosis occluding the vessel lumen has been widely indicated as the crucial acute event causing peripheral tissue ischaemia. A complex cross-talk between systemic and intraplaque inflammatory mediators has been shown to regulate maturation, remodeling and final rupture of an atherosclerotic plaque. Matrix metalloproteinases (MMPs) are proteolytic enzymes (released by several cell subsets within atherosclerotic plaques), which favour atherogenesis and increase plaque vulnerability. Thus, the assessment of intraplaque levels and activity of MMP might be of pivotal relevance in the evaluation of the risk of rupture. New imaging approaches, focused on the visualisation of inflammation in the vessel wall and plaque, may emerge as tools for individualised risk assessment and prevention of events. In this review, we summarize experimental findings of the currently available invasive and noninvasive imaging techniques, used to detect the presence and activity of MMPs in atherosclerotic plaques.     

Noninvasive imaging of atherosclerotic plaque in the arch of the aorta with transcutaneous B-mode ultrasonography

Atherosclerotic plaque at the arch of the aorta has been identified as a potential source for atheroembolic stroke. Imaging of aortic arch plaque can be performed with transesophageal echocardiography (TEE), but TEE is an invasive procedure. A new noninvasive method has been developed to image aortic arch plaque employing transcutaneous real time B-mode ultrasonography with color flow duplex Doppler. B-mode imaging has an 86% accuracy for identifying complex aortic arch plaques as compared with TEE. Noninvasive imaging of the aortic arch can be employed in diagnosing the etiology of cerebrovascular disease in patients with stroke or transient ischemic attack in conjunction with duplex B-mode sonography of the extracranial carotid arteries. It also provides a noninvasive method for studying atherosclerotic plaque in the aortic arch which is applicable for investigational studies of the mechanisms of atherosclerosis and evaluation of pharmacological agents designed to treat atherosclerotic disease.     

颅内动脉粥样硬化斑块高分辨率磁共振成像研究进展

颅内动脉粥样硬化斑块被认为是中国人群中导致缺血性卒中的主要因素之一,随着影像 学的技术进展,高分辨率磁共振成像为无创性评价颅内动脉粥样硬化斑块的成分构成和特点、与 动脉狭窄的关系等方面提供了更精准的成像技术,其研究逐渐成为热点。动脉粥样硬化斑块在磁 共振成像中3维时间飞跃序列（3D time of flight,3D-TOF）及T1序列（T1-wei ghted i magi ng,T1WI ）、T2序 列（T2-weighted imaging,T2WI）、质子序列（proton density weighted imaging,PDWI）、磁化准备快速梯 度回波序列（magnetization prepared rapid gradient echo,MP-RAGE）、强化序列（T1 contrast enhanced weighted imaging,T1+C）上有不同的信号特点,这些序列也是研究颅内动脉粥样硬化斑块影像学特点 及其与临床预后关系的主要方向。     

不同机制症状性颅内动脉粥样硬化性疾病的高分辨率磁共振特征

目的 探究不同机制大动脉粥样硬化型卒中患者颅内动脉粥样硬化斑块的特征是否存在差别。 方法 依据中国缺血性卒中亚型（Chinese Ischemic Stroke Subclassification,CISS）分型标准连续收录症 状性颅内动脉粥样硬化性疾病（symptomatic intracranial atherosclerotic stenosis,sICAS）患者作为研究 对象,并依据梗死机制将sICAS患者分组,无症状性ICAS患者作为对照组。对所有入组患者的责任动 脉管壁行高分辨率磁共振（high-resolution magnetic resonance imaging,HR MRI）扫描,比较不同机制 sICAS患者动脉粥样硬化斑块的特征。 结果 共有56例sICAS患者、9例无症状性ICAS患者纳入本研究。与无症状性ICAS患者比较,sICAS患者 颅内动脉粥样硬化斑块的特征表现为：病变局部正性重构率高、负性重构率低;动脉粥样硬化斑块 更多位于穿支动脉开口处。但不同机制sICAS患者颅内动脉粥样硬化斑块特征未发现明显差别。入组 患者中10例经经颅多普勒（transcranial Doppler,TCD）/磁共振血管成像（magnetic resonance angiography, MRA）检查未发现颅内动脉狭窄,经HR MRI检查发现存在粥样硬化斑块。 结论 HR MRI有助于发现sICAS患者不稳定斑块的存在,但不同机制sICAS患者颅内动脉粥样硬化斑 块的HR MRI特征差异无显著性。     

High-field atherosclerotic plaque magnetic resonance imaging

Manifestations of atherosclerotic plaque in different arterial beds range from perfusion deficits to overt ischemia such as stroke and myocardial infarction. Atherosclerotic plaque composition is associated with its propensity to rupture and cause vascular events. Magnetic resonance (MR) imaging of atherosclerotic plaque using clinical 1.5 T scanners can detect plaque composition. Plaque MR imaging at higher field strengths offers both opportunities and challenges to improving the high spatial resolution and contrast required for this type of imaging. This article summarizes the technological requirements required for high-field plaque MR imaging and its application in detecting plaque components.     

高分辨磁共振成像在基底动脉粥样硬化性疾病中的临床应用

高分辨磁共振成像可以清晰显示基底动脉的管壁和斑块结构,这对于探究基底动脉粥样硬化性重塑、斑块成分和斑块分布具有重要临床价值,有助于阐明基底动脉粥样硬化与缺血性卒中的关系。     

B-mode ultrasound and spiral CT for the assessment of carotid atherosclerosis

More studies on the natural history of carotid artery plaques are needed to predict more reliably which plaque types or features are the most dangerous (see Table 2). Studies on carotid and coronary endarterectomy specimens indicate a dynamic process of rupture, thrombus formation, healing, and remodeling of the plaque. A plaque from a symptomatic patient may not show any signs of plaque rupture if the plaque has healed or evolved since the debut of symptoms. Selection of high-risk symptomatic patients with carotid atherosclerosis for medical or surgical treatment requires reliable, noninvasive, and cost-effective imaging methods. B-mode ultrasonography can be used for detection of early (IMT) as well as late (plaque morphology) atherosclerotic disease. Plaque morphology evaluation on spiral CT imaging is only for research and not yet for clinical use. Asymptomatic patients with carotid atherosclerosis hardly benefit from surgical treatment, as the minimal decrease in ischemic stroke risk is almost equal to the risk of perioperative stroke or death. A high degree of carotid stenosis measured using conventional angiography is an accepted risk factor for stroke but does not identify all vulnerable plaques. Echolucency on ultrasound B-mode imaging can be included as an important parameter in this risk stratification, as it appears to predict rupture-prone, lipid-rich plaques in the mild to severely stenotic carotid artery of a symptomatic patient. The subjective evaluation of plaque morphology on B-mode ultrasound should be complemented or substituted with objective evaluation such as videodensitometric analysis. This method is commercially available and is a relatively cheap and investigator-independent solution, but more studies are required to determine the exact contribution of echolucency to stroke risk. Furthermore, the evaluation of plaque morphology using ultrasound B-mode is still subject to large variations and observer-dependence, limiting its clinical use. In contrast, carotid IMT measurements are reliable to monitor progression and regression of early carotid disease as well as the impact of interventions. This method, however, suffers when used in severely diseased vessels where the boundaries of the IMT complex are hard to distinguish in all segments of the artery. Spiral CT imaging is a preliminary test for plaque characterization, as it primarily identifies calcification but not the more relevant lipid component. Moreover, it is time and resource demanding and involves use of both contrast and radiation, increasing the risk of allergic events and cancer. Standardization and continuous quality control are important, as are consensus agreements on how to quantify lesions (especially IMT), calibrate and standardize B-mode images and outline the plaque, and analyze data. The development of imaging methods for atherosclerotic research is currently fast and promising. This progress is most necessary, considering the very high demands for surrogate endpoints and risk markers in clinical intervention studies. Whether ultrasonic plaque characterization can be implemented in broad general clinical practice, for example, in screening of individuals at high risk of developing atherosclerosis and ischemic events, has to be based upon data from large prospective studies with long-term follow-up. IMT is already used in population screening, as in the ARIC study [9,101].     

血浆同型半胱氨酸与脑梗死TOAST亚型相关性研究

目的:探讨血浆同型半胱氨酸(Hcy)浓度与脑梗死TOAST亚型间的相关性。方法:362例脑梗死患者依据TOAST分型诊断标准确定亚型,酶法测定晨起空腹血浆Hcy浓度,秩和检验Hcy水平与TOAST亚型间相关性;彩色多普勒超声检查根据颈动脉内-中膜厚度、血管内膜形态、血流频谱将粥样硬化斑块分为易损和非易损斑块组,对比分析Hcy水平与斑块性质间关系。结果:①大动脉粥样硬化(LAA)型脑梗死患者血浆Hcy水平、高同型半胱氨酸血症(HHcy)发生率显著高于TOAST其他亚型;将心源性栓塞型、小动脉闭塞型、其他原因型、病因不明型4亚型合并为非LAA组后,LAA型Hcy水平和HHcy发生率仍然最高(P<0.05)。②Logistic回归分析显示HHcy是LAA型脑梗死的独立危险因素(OR=7.73,95% CI:2.99~20.01)。③LAA型脑梗死易损斑块组患者血浆Hcy浓度和HHcy发生率均显著高于非易损斑块组(P<0.05);多因素分析显示HHcy和糖尿病是易损斑块的独立危险因素。结论:血浆Hcy增高与TOAST分型中LAA亚型、颈动脉粥样硬化易损斑块密切相关,提示HHcy可能通过引发大动脉粥样硬化而导致脑梗死。