虚拟支架快速仿真技术及主动脉夹层介入治疗力学机理研究

主动脉夹层是一类高危血管疾病，胸主动脉腔内修复术（TEVAR）是B型夹层的主要治疗方法，通过植入带膜支架封堵裂口并支撑真腔。科学的术前规划有助于保证该治疗方法的安全性和有效性，这需要兼具时效性和准确性的支架仿真算法以预测支架-管壁接触效果，以及针对安全性和有效性的力学机理研究以预判血管损伤和血流传输的改善程度。为此，本项目拟：1）基于自适应网格快速变形技术和力学接触分析，构建兼具快速计算和真实物理意义的虚拟支架算法；2）基于力学实验和组织学分析，研究血管组织和支架的力学属性，为虚拟支架算法提供力学接触参数，为支架安全性研究提供血管损伤临界条件；3）基于计算力学，研究术后血流动力学参数（假腔分流比减小率、真假腔压强差平衡点远移位置）与术后主动脉形态转归的数学关系，为支架有效性研究提供血流功能量化评价方法。此研究为TEVAR术前规划提供快速支架展开效果预测和力学评价，以提高其安全性和有效性。

Aortic dissection is a vascular disease with high mortality. Thoracic endovascular aortic repair is often applied in Stanford type-B aortic dissection, which seals the primary entry and supports true lumen remodeling. Wise planning of the stent-graft implantation would improve the safety and effectiveness of this treatment. However, this requires real-time computational approach to simulate the stent-vessel mechanical contact, as well as the mechanical analyses that quantitatively evaluate device-induced vessel injury and the improvement of hemodynamics. Thus, the studies in this project include: 1) establishing the physically-based fast simulation framework via auto-adaptive simplex deformable mesh and mechanical contact analysis, and validating the accuracy of the simulations by post-treatment medical images ; 2) analyzing the material properties of the dissected aorta and stent-graft based on uniaxial-tensile test and radial compressive test respectively, providing mechanical parameters for the contact model in the virtual stenting algorithm and offering the mechanical criteria for vessel injury ; 3) quantifying the flow division of the false lumen and the luminal pressure difference based on computational hemodynamic analyses, and establishing the relationship between these parameters to the configuration change of the false lumen during follow-up, so that to propose the parameters that are able to quantitatively evaluation the post-treatment hemodynamic improvement. This study provide simulation and evaluation components for virtual TEVAR planning, and thus may improve the safety and effectiveness of this treatment.