外科创新技术/器械临床研究方法学——IDEAL框架与推荐系列文章之二:IDEAL报告规范解读

严格遵守报告规范有助于研究者完整、清晰和透明地报道方法学和研究结果.目前国际报告规范网站收录的与外科干预相关的报告指南主要针对某种研究设计类型和部分研究内容.因IDEAL框架是对外科创新技术发展的所有阶段进行评估,而每个阶段都有其核心问题和关键要素,若仅采用已有针对设计类型的报告规范可能忽略这些重要特征,导致研究者不能...     

Group-wise construction of reduced models for understanding and characterization of pulmonary blood flows from medical images

3D computational fluid dynamics (CFD) in patient-specific geometries provides complementary insights to clinical imaging, to better understand how heart disease, and the side effects of treating heart disease, affect and are affected by hemodynamics. This information can be useful in treatment planning for designing artificial devices that are subject to stress and pressure from blood flow. Yet, these simulations remain relatively costly within a clinical context. The aim of this work is to reduce the complexity of patient-specific simulations by combining image analysis, computational fluid dynamics and model order reduction techniques. The proposed method makes use of a reference geometry estimated as an average of the population, within an efficient statistical framework based on the currents representation of shapes. Snapshots of blood flow simulations performed in the reference geometry are used to build a POD (Proper Orthogonal Decomposition) basis, which can then be mapped on new patients to perform reduced order blood flow simulations with patient specific boundary conditions. This approach is applied to a data-set of 17 tetralogy of Fallot patients to simulate blood flow through the pulmonary artery under normal (healthy or synthetic valves with almost no backflow) and pathological (leaky or absent valve with backflow) conditions to better understand the impact of regurgitated blood on pressure and velocity at the outflow tracts. The model reduction approach is further tested by performing patient simulations under exercise and varying degrees of pathophysiological conditions based on reduction of reference solutions (rest and medium backflow conditions respectively).