Device Design for Treatment of Aortic Disease

本项目的总体目标是提供一套工具，用于评价主动脉疾病腔内修复术中所用器械的性能。 血管内治疗的应用激增。 然而，关于植入设备的重要特征应该是什么，几乎没有科学指导。 本项目将提供用于确定器械特征的血流动力学影响的工具，并将帮助确定最适合患者的设计。该项目的主要目的是扩展我们的计算流体动力学能力，以快速描述和评价用于治疗腹主动脉瘤的器械上的血液动力学力。 将通过创新的成像技术验证模拟软件。将开发数值算法，以描述介入前和模拟器械插入后血管系统中的血流动力学。 这些能力将允许评估倾向于导致覆膜支架移位或拆卸的力。 它还将提供降低存在具有血栓形成潜力的显著再循环区域的可能性的能力。先进的成像方法将用于提供心动周期内多个点处管腔表面的完整描述。 磁共振成像脉冲序列设计、射频线圈和造影剂的使用的改进将被追求以提供这种能力。 此外，为了建立数值计算的边界条件，将在介入前使用磁共振测速仪测量流速。 最后，将招募计划进行AAA修复的患者队列，并将患者特定血流动力学力计算结果与器械形态的时间变化进行比较。该项目是成像科学家，流体动力学工程师和临床医生之间的合作努力。 它将提供一个系统的工程框架，在其中可以改进介入器械的设计和功能。将识别并消除器械失效的潜在来源。 这些改进将使未来几年可能接受血管内覆膜支架治疗的大量患者受益。

The overall goal of this project is to provide a set of tools for evaluating the performance of devices that are used in the endovascular repair of aortic disease. There has been a surge in the application of endovascular treatment. However, there is little scientific guidance on what the important features of an implanted device should be. This project will provide the tools for determining the hemodynamic impact of device characteristics and will assist in determining the most suitable design on a patient-by-patient basis. The primary aim of this project is to extend our Computational Fluid Dynamics capabilities for the rapid description and evaluation of hemodynamic forces on devices used for treating aneurysms of the abdominal aorta. Validation of the simulation software will be provided by innovative imaging techniques. Numerical algorithms will be developed to describe the hemodynamics in the vasculature before intervention and following the simulated insertion of a device. These capabilities will permit the assessment of the forces that tend to cause a stent- graft to migrate or to disassemble. It will also provide the ability to reduce the likelihood that there will be regions of pronounced recirculation with potential for thrombus formation. Advanced imaging methods will be used to provide a full description of the lumenal surface at multiple points through the cardiac cycle. Improvements in Magnetic Resonance Imaging pulse sequence design, radio frequency coils, and the use of contrast agents will be pursued to provide this capability. In addition, to establish boundary conditions for the numerical computations, flow velocities will be measured pre intervention using Magnetic Resonance Velocimetry. Finally, a cohort of patients scheduled for AAA repair will be recruited and the results of patient- specific computations of hemodynamic forces will be compared to temporal changes in device conformation. This project is a collaborative effort between imaging scientists, fluid dynamics engineers, and clinicians. It will provide a systematic engineering framework in which the design and function of interventional devices can be improved. Potential sources of device failure will be identified and eliminated. These improvements will benefit the large numbers of individuals who are likely to receive treatment with endovascular stent-grafts in the coming years.