Assessing Microstructure of Carotid Disease with MRI/MRS

描述(申请人提供)：申请人是一名神经放射科医生 对MR和CT方法在中风研究中的应用感兴趣， 眼前的目标是扩大对颈动脉的理解 动脉粥样硬化及其与中风的关系。这其中的一个主要重点是 对应用程序的开发有一个详细的了解结构 动脉壁和动脉粥样硬化斑块的MR和CT成像技术。 另一个主要重点将放在掌握生物统计学以 改进研究设计以及数据收集和解释。长期目标 是获得成为研究的独立调查者的工具 卒中。 中风是导致死亡的第三大原因，也是 美国的残疾，以及所有缺血的很大一部分 中风是由颈动脉粥样硬化症引起的。中风通常在中风之前 通过神经系统症状，通过及时的干预是可以预防的。这个 动脉狭窄程度是一个主要的危险因素，但有证据表明 与血管收缩大小无关的因素在 引起症状。这些包括形态和成分 动脉粥样硬化斑块本身。 将追求以下具体目标来评估以下假设： 斑块成分是症状的独立预测因子：1)一项初步研究 将在有症状和无症状的患者(N=50) 临床上有显著颈动脉狭窄(&gt；70%)的患者 接受颈动脉内膜切除术(CEA)。这些病人会 在1.5特斯拉进行颈动脉的高分辨率磁共振成像。2)之后 CEA，将在9.4特斯拉对完整的斑块样本进行显微成像 并与活体成像进行比较。还将进行Micro-CT成像。 完整样品的13-C核磁共振波谱将在9.4特斯拉下进行， 斑块提取后将重复采集。斑块脂质 将研究概况和钙含量，以此作为表征 并评估斑块特征和斑块的相关性 病人的症状学。

DESCRIPTION (provided by the applicant): The applicant is a neuroradiologist interested in application of MR and CT methodologies to the study of stroke, with the immediate goal of obtaining a broadened understanding of carotid atherosclerosis and its relationship to stroke. One major emphasis of this application is toward the development of a detailed understanding of structural MR and CT techniques for imaging the arterial wall and atherosclerotic plaque. Another major emphasis will be placed on gaining a mastery of biostatistics to improve study design and data collection and interpretation. The long-term goal is to acquire tools to become an independent investigator in the study of stroke. Stroke is the third leading cause of mortality and the leading cause of disability in the United States, and a significant fraction of all ischemic strokes are caused by carotid atherosclerotic disease. Often stroke is preceded by neurologic symptoms and may be preventable with timely intervention. The degree of arterial stenosis is a major risk factor, but there is evidence that factors unrelated to the size of the vascular constriction play a role in causing symptoms. These include the morphology and composition of the atherosclerotic plaque itself. The following specific aims will be pursued to evaluate the hypothesis that the plaque composition is an independent predictor of symptoms: 1) A pilot study will be initiated wherein symptomatic and asymptomatic patients (N = 50 each) with clinically significant carotid stenosis (>70%) who will subsequently undergo carotid endarterectomy (CEA) will be recruited. These patients will undergo high-resolution MR imaging of the carotid artery at 1.5 Tesla. 2) After CEA, microimaging of the intact plaque specimen will be performed at 9.4 Tesla and compared with in vivo imaging. Micro-CT imaging will also be performed. 13-C NMR spectroscopy of the intact specimen will be performed at 9.4 Tesla, and the acquisitions will be repeated after plaque extraction. Plaque lipid profile and calcium content will be studied as a means to characterize the lesion and evaluate the association between plaque characteristics and patients' symptomatology.