High Framerate Plane-Wave Variance of Acceleration and Vector Flow Imaging for the Characterization of Atherosclerotic Plaque Morphology and Assessment of Vascular Hemodynamics

项目总结 需要微创方法来筛选缺血性中风的早期预测因素 应对心血管疾病病例的增加，同时减少不必要的颈动脉 动脉内膜切除术，这是一种侵入性但预防性的移除斑块的手术。现行的金本位 对于诊断，双功超声通常用于检测严重闭塞的血管系统，但只需注意 狭窄程度不足以衡量斑块破裂的易损性。声辐射力脉冲 (ARFI)超声技术最近成为区分易损斑块和稳定斑块的一种潜在方法。 通过描绘斑块成分。然而，由于该技术依赖于高强度的发射 聚焦声脉冲虽然是非破坏性的，但组织加热的潜力限制了更广泛的使用，而 长时间的数据收集增加了运动伪像破坏数据收集和 对结果的生理学解释。使用一种新的超快ARFI成像序列评估两者 斑块结构和周围血流动力学可能在减少 获取时间，减少声学加热，并改进风险预测。存在着压倒性的 斑块生长和破裂的机制受作用于血管壁的剪切力控制的证据。 除了更有效地检测斑块成分外，还可以监测剪应力的动态变化 可能被证明是一种新的方法来区分患有脆弱动脉粥样硬化斑块的高危患者与那些患有 稳定的斑块表型。我们建议进一步开发和表征超声并行传输 序列以快速连续地对组织成像，并另外检测周围的多方向血流 脉管系统。将ARFI弹性成像、高帧速率成像和流动信息相结合，可实现实时 在整个心脏周期中对斑块环境进行可实现的评估。因此，与 这项研究的目标是为未来的中风风险评估进一步开发诊断成像工具。

PROJECT SUMMARY The need for minimally invasive methods for screening early predictors of ischemic stroke are required to combat the increase in cardiovascular disease cases while reducing number of unnecessary carotid endarterectomies, which are invasive but preventative procedures to remove plaques. The current gold-standard for diagnosis, duplex ultrasound, is often used to detect heavily occluded vasculature, but simply noting the degree of stenosis is an insufficient measure of plaque rupture vulnerability. Acoustic Radiation Force Impulse (ARFI) ultrasound technique recently emerged as a potential method to separate vulnerable from stable plaques through delineation of plaque components. However, as the technique relies on emission of high intensity focused acoustic pulses, although nondestructive, the potential for tissue heating limits extended uses, while the long period of data collection increases opportunities for motion artifacts to corrupt data collection and physiological interpretation of results. The use of a new ultrafast ARFI imaging sequence to evaluate both plaque structure and surrounding hemodynamics may provide significant advancement in reducing acquisition time, reducing acoustic heating, and improving risk prediction. There exists overwhelming evidence that mechanics of plaque growth and rupture are governed by shear forces acting on the vessel walls. Monitoring the dynamics changes in shear stress in addition to more efficiently detecting plaque composition may prove a novel avenue for discerning at risk patients with vulnerable atherosclerotic plaques vs those with stable plaque phenotypes. We propose to further develop and characterize ultrasound parallel transmit sequences to image tissue in rapid succession and additionally detect multi directional blood flow around the vasculature. Combining the ARFI elastography, high framerate imaging, and flow information allows a real-time realizable assessment of the plaque environment throughout the entire cardiac cycle. Therefore, meeting the aims of the study will further develop diagnostic imaging tools for future stroke risk assessment.