Structural Stability of Carotid Plaque and Symptomatology

描述（由申请人提供）：本研究探讨了“沉默”卒中中颈动脉粥样硬化斑块结构稳定性与非运动症状发展（包括脑萎缩和认知能力下降）之间的关系。它解决了颈动脉栓塞在“无声”中风及其认知后遗症中的作用问题。本研究以人颈动脉内膜切除术患者为研究对象，研究三个具体目的。第一种是利用超声将斑块弹性及其机械应变特征的发展与搏动和斑块的组织病理生理学与溃疡、出血和稳定纤维帽在这些机械应变特征点上的变薄联系起来。第二个检查超声检测斑块的弹性应变特征和经颅多普勒TCD检测微栓子的存在。第三组观察超声应变缺陷、微栓子、认知能力下降和脑MRI局灶性和全身性萎缩的证据。了解导致颈动脉斑块机械不稳定和栓塞风险的结构斑块异常，将为那些不仅可能遭受经典发作性大卒中，而且可能遭受脑“无声”卒中和认知能力下降的微栓子的功能进行性下降的个体提供病理生理机制。

DESCRIPTION (provided by applicant): This study examines the issue of "silent" strokes in the relationship between the structural stability of atherosclerotic carotid plaque and the development of nonmotor symptomatology, including brain atrophy and cognitive decline. It addresses the question of the role of carotid emboli in "silent" stroke and their cognitive sequelae. The study uses human carotid endarterectomy patients to study three specific aims. The first uses ultrasound to relate plaque elasticity and its development of mechanical strain features with pulsation and the histopathophysiology of the plaque for ulcer, hemorrhage and thinning of stabilizing fibrous cap at the point of these mechanical strain features. The second examines ultrasound detected elasticity strain features in the plaques and the presence of transcranial Doppler TCD detectable microemboli. The third looks at ultrasound strain deficits, microemboli, cognitive decline and brain MRI evidence of focal and generalized atrophy. Understanding the structural plaque abnormalities, which render a carotid plaque mechanically unstable and at risk of embolization will demonstrate a pathophysiologic mechanism in individuals who are likely to suffer not only classic episodic major strokes, but also functional progressive decline from the contribution of microemboli to cerebral "silent" stroke and cognitive decline. PUBLIC HEALTH RELEVANCE: Cerebrovascular disease remains a major health problem with increasing impact on an aging population. Studies suggest that clinical and "silent" stroke affects 11 million Americans per year. Vascular aging from atherosclerosis is a major contributor to this problem. For this reason, we propose a study of carotid atherosclerosis developing novel markers for carotid plaque instability which may result in the presence of multiple microemboli, which in turn may contribute to increased symptomatology, both classic strokes, as well as, cognitive decline. If successful, this study will greatly increase our understanding of the pathophysiology of symptoms from atherosclerosis, as well as, lead to the development of potential new measures to detect this disorder noninvasively.