【作者】 李明利；

【导师】 金征宇；

【作者基本信息】 中国协和医科大学 ， 影像医学与核医学， 2004， 博士

【摘要】 研究背景和目的 缺血性脑血管病是严重影响人类生命及生活质量的常见病、多发病，致死率和致残率非常高。利用各种影像学方法进行急性脑梗死发生后的早期和超早期诊断是近年来研究的重点。这些研究为急性脑梗死的治疗提供了极大的帮助，但是如果能够在梗死发生之前准确地预测到梗死的发生并采取预防性的治疗措施，无疑具有更重要的意义。已有的研究表明颈动脉闭塞性疾病是引起缺血性脑中风的重要危险因素。狭窄程度，粥样斑块的性质以及脑血液动力学的变化都可能与中风的发生率有关。随着多层螺旋CT应用于临床，使一次检查完成上述危险因素预测指标的评价成为可能。研究表明，CTA可以准确的评价颈动脉的狭窄程度。但CT能否敏感的发现由狭窄或闭塞导致的血液动力学变化，能否判断粥样斑块的性质尚不明确。另外，关于脑血液动力学损害是否为脑中风的高危因素尚存在争议。本研究针对上述问题进行了探索，旨在探讨利用多层螺旋CT技术预测脑中风危险性的应用价值，以提高脑血管病的诊断和中风的预测水平。 研究内容 1．为了研究脑血液动力学的损害在缺血性脑梗死形成中的作用机制，我们通过结扎SD大鼠(300—350g)双侧椎动脉和右侧颈总动脉建立了一个模拟颈动脉闭塞的单侧前脑慢性低灌注缺血模型。并分别在3天(n=10)和21天(n=10)对此模型进行了病理和CT灌注评价，评价结果与假手术组(n=10)进行了对照。然后，将35只大鼠模型随机分成5组，分别在1，3，7，14，21天时观察了脑血液动力学的演变，结果与假手术组(n=7)对照。最后，利用10只模型大鼠和10只假手术大鼠，在术后7天时经左侧颈外动脉注入微栓子，研究了脑血液动力学损害与栓塞性脑梗死危险性增高的关系。 2．为了评价CT灌注和CTA技术应用于颈动脉闭塞性病变的可行性，探讨多层螺旋CT多序列成像的临床应用价值，我们首先探讨了多层螺旋CT头颈部血管成像的技术。针对16排多层螺旋CT扫描速度快的特点，评价了低剂量对比剂血管成像的可行性(75ml 12例，55ml 8例)，并对重建技术进行了对比评价。然更多还原

【Abstract】 BackgroundStroke is the most common life-threatening neurological disease and remains the major cause of disability among adults. In recent years, imaging studies have focused on the diagnosis of hyperacute stroke, and those studies have improved the treatment and reduced the mortality of stroke. But there will be of more clinical significance if we could predict the occurrence of stroke and take prophylactic treatment for patients with higher risk of stroke. It has been proved that severe carotid occlusive disease is the major factor of ischemic stroke. The degree of carotid stenosis, plaque characteristics, and the cerebral hemodynamic impairment are all relative to the occurrence of stroke .With the advanced multi-slice CT, it has become possible to evaluate those variables in one-time CT examination.Aims of the thesis1. The overall aim is to improve the diagnosis and prediction of stroke in patients with severe carotid occlusive diseases in clinical MSCT analysis.2. To investigate the hemodynamic risk factors for stroke using proper animal models.3. To evaluate CT perfusion in animal models with chronic cerebral hypoperfusion.4. To evaluate the combination of CTP and CTA in patients with symptomatic carotid occlusive disease.Materials and MethodsAnimal experiment1. the rat model was carried out on male Sprague-Dawley rats (300-350g in body weight). The bilateral vertebral arteries were occluded by electrocoagulation,then the right common carotid artery was ligated 1 hours later.2. One control group (false operative, n=10) and two rat model groups (n=10 for each更多还原