Mösges R, Büchner B, Kleiner M, Freitas R, Hörschler I, Schröder W
Institute of Medical Statistics, Informatics and Epidemiology, University of Cologne, Germany.
B-ENT. 2010;6(3):161-5.
Standard methods to examine nasal flow are experimental and do not yield locally detailed results. Using the Lattice-Boltzmann method (LBM), we computed nasal air flow and investigated the relationship between nasal obstruction and anatomical conditions. Because of its mathematical structure, the LBM can be immediately applied to various nasal cavities that are characterized by an extremely intricate geometry. In the present study, the higher efficiency of the LBM allowed for high resolution and detailed analysis of the flow structures in the nasal cavity.
Based on a previously validated simulation of nasal airflow in an artificial model, we acquired the nasal geometry of an individual by computed tomography and applied the LBM to numerically solve Navier-Stokes equations and thereby determine nasal flow.
In contrast to frequently used standard finite-volume methods, our method facilitated grid generation and computational parallelisation. The grid modelling of the nasal cavity comprised 4.9 million nodes and the computational time on a high-performance computing cluster was less than 12 hours. The velocity and pressure of the calculated airflow was visualized in every tiny recess of the nasal cavity and areas of interest could be easily identified.
Computer-assisted visualization of patients' 3D nasal flow structures may be useful for diagnosis, and for planning surgical interventions. Although numerical analysis is far from real-time, and the generation of geometric models still requires a large amount of manual interaction, our simulation approach will be useful for nasal flow research.
检查鼻腔气流的标准方法是实验性的，无法得出局部详细结果。我们使用格子玻尔兹曼方法（LBM）计算鼻腔气流，并研究鼻塞与解剖条件之间的关系。由于其数学结构，LBM可以立即应用于各种具有极其复杂几何形状特征的鼻腔。在本研究中，LBM的更高效率使得能够对鼻腔内的流动结构进行高分辨率和详细分析。
基于先前在人工模型中验证的鼻腔气流模拟，我们通过计算机断层扫描获取个体的鼻腔几何形状，并应用LBM数值求解纳维-斯托克斯方程，从而确定鼻腔气流。
与常用的标准有限体积法相比，我们的方法便于网格生成和计算并行化。鼻腔的网格模型包含490万个节点，在高性能计算集群上的计算时间不到12小时。计算出的气流速度和压力在鼻腔的每个微小凹陷处都能可视化，感兴趣的区域也很容易识别。
计算机辅助可视化患者的三维鼻腔流动结构可能有助于诊断和手术干预规划。尽管数值分析远非实时，并且几何模型的生成仍然需要大量的人工交互，但我们的模拟方法将对鼻腔气流研究有用。
