High Frame Rate Vascular Ultrasound Innovations for Complex Flow Imaging

在人体动脉中呈现流动动力学的技术在血管异常的检测中非常有用。一个关键的应用领域是颈动脉粥样硬化的诊断，颈动脉粥样硬化是一种血管疾病，其特征是形成斑块，使向大脑供血的循环分支变窄。我的研究计划将寻求通过设计新的三维（3D）超声成像解决方案，在血管诊断方面取得重大进展，该解决方案可以在脉动脉冲周期的不同阶段检查主要动脉（如颈动脉）中复杂流动模式的时空演变。具体而言，我的团队将致力于： 1)设计高帧率3D复杂血流成像框架，实现动脉容积内复杂血流的时间分辨动态绘制（亚毫秒时间分辨率;远远超过每秒20-30帧的典型视频显示速率）; 2)为系统硬件（阵列传感器、接口电子设备）和实时计算（图形处理单元处理）制定新的解决方案，这对实际实现高帧率3D复杂流动成像至关重要; 3)设计基于流动矢量分析（壁剪切率、涡度和螺旋度的时空映射）的血流动力学参数可视化算法，以从复杂的流动模式中获得功能性见解; 4)通过设计3D流动模型（例如动脉瘤和血管树模型）并进行一系列体外流动实验，分析我们的成像创新的实际效果。 我们提出的创新努力将导致第一个非侵入性医学成像解决方案，可以有效地跟踪3D复杂的血流动力学在即时护理设置下的时间分辨方式，而不使用电离辐射。它们将在促进临床医生对动脉粥样硬化等血管病变做出更明智的诊断方面发挥促进作用。反过来，血管病患者将成为主要受益者;例如，改善颈动脉粥样硬化的诊断可以帮助降低中风的发病率，在加拿大，中风每年造成14，000人死亡。这项研究还将有利于培养加拿大生物医学工程的研发人才库，加强加拿大在超声成像研发方面的核心竞争力，确立加拿大在该领域的全球领导者地位。

Technologies that render flow dynamics in human arteries are highly useful in the detection of vascular abnormalities. One key application area is the diagnosis of carotid atherosclerosis, a vascular disease marked by the formation of plaques that narrow the circulatory branch supplying blood to the brain. My research program will seek to make significant advances in vascular diagnostics by engineering new three-dimensional (3D) ultrasound imaging solutions that can examine, over different phases of a pulsatile pulse cycle, the spatiotemporal evolution of complex flow patterns in major arteries such as the carotid. Specifically, my team will aim to: 1) Design a high-frame-rate 3D complex flow imaging framework to achieve time-resolved dynamic rendering of complex flow inside arterial volumes (sub-millisecond time resolution; well beyond the typical video display rate of 20-30 frames per second); 2) Formulate new solutions for system hardware (array transducer, interfacing electronics) and real-time computing (graphics processing unit processing) that are essential to practical realization of high-frame-rate 3D complex flow imaging; 3) Devise hemodynamic parameter visualization algorithms based on flow vector analysis (space-time mapping of wall shear rate, vorticity, and helicity) to derive functional insights from complex flow patterns; 4) Analyze the practical efficacy of our imaging innovations by designing 3D flow phantoms (e.g. models of aneurysms and vascular trees) and performing a series of flow experimentation in vitro. Our proposed innovation endeavors will lead to the first non-invasive medical imaging solutions of their kind that can effectively trace 3D complex hemodynamics in a time-resolved manner under point-of-care settings and without using ionizing radiation. They will play an enabling role in facilitating clinicians to make more informed diagnosis of vascular pathologies such as atherosclerosis. In turn, vascular patients will be the principal beneficiaries; for instance, improved diagnosis of carotid atherosclerosis can help reduce the incidence of stroke, which is responsible for 14,000 deaths per year in Canada. This research will also benefit the grooming of Canada's R&D talent pool in biomedical engineering and the strengthening of Canada's core competence in ultrasound imaging R&D, establishing Canada's position as a global leader in this field.