Burrowes Kelly S, Tawhai Merryn H
Bioengineering Institute, The University of Auckland, Private Bag 92019, Auckland, New Zealand.
Respir Physiol Neurobiol. 2006 Dec;154(3):515-23. doi: 10.1016/j.resp.2005.11.007. Epub 2005 Dec 28.
A computational model of blood flow through the human pulmonary arterial tree has been developed to investigate the mechanisms contributing to regional pulmonary perfusion in the isolated network when the lung is in different orientations. The arterial geometric model was constructed using a combination of computed tomography and a volume-filling branching algorithm. Equations governing conservation of mass, momentum, and vessel distension, incorporating gravity, were solved to predict pressure, flow, and vessel radius. Analysis of results in the upright posture, with and without gravity, and in the inverted, prone, and supine postures reveals significant flow heterogeneity and a persistent decrease in flow in the cranial and caudal regions for all postures suggesting that vascular geometry makes a major contribution to regional flow with gravity having a lesser role. Results in the isolated arterial tree demonstrate that the vascular path lengths and therefore the positioning of the pulmonary trunk relative to the rest of the network play a significant role in the determination of flow.
已开发出一种通过人体肺动脉树的血流计算模型，以研究在肺处于不同方位时，孤立网络中区域肺灌注的促成机制。动脉几何模型是使用计算机断层扫描和体积填充分支算法相结合构建的。求解包含重力的质量、动量和血管扩张守恒方程，以预测压力、流量和血管半径。对直立姿势（有重力和无重力）、倒立姿势、俯卧姿势和仰卧姿势的结果分析表明，所有姿势下在头侧和尾侧区域均存在显著的血流异质性以及血流持续减少，这表明血管几何形状对区域血流起主要作用，而重力的作用较小。孤立动脉树的结果表明，血管路径长度以及因此肺动脉主干相对于网络其余部分的定位在流量的确定中起重要作用。
