Rhinosurgical therapy planning via endonasal airflow simulation

Abstract

Nowadays, Computational Fluid Dynamics (CFD) methods play an important part in the production process of the automotive industry. Progress in recent years has made possible highly sophisticated airflow‐simulation models that are used in engineering for optimization and verification of aerodynamics. The key purpose of the Simulation Tool for Airflow in the human Nose (STAN), developed at the Darmstadt University of Technology in cooperation with the University Hospital in Greifswald, is to use these techniques to support the rhinosurgeon in diagnosis and planning of therapy (Frühauf T, Mlynski G. Simulation and visualization of the air flow in the human nose. Proceedings of the First World Congress on Computational Medicine, Austin, Texas, 1994). A system has been developed that realizes a three‐dimensional (3D) reconstruction of the endonasal cavities based on computer tomography (CT) scans. This semiautomatic reconstruction method requires minimal manual intervention. The surface model is used to create an unstructured 3D volume mesh suitable for finite volume simulations. In this way, an individual simulation based on patient‐specific data can be realized. At the University Hospital in Greifswald, experimental investigations and measurements are made in nasal models to verify the simulation result. The goal of this project is to investigate individual nasal complaints and to detect respiratory disorders. The surgeon should be able to simulate the disordered respiration before performing a surgical procedure, and thereby increase the effectiveness of surgical planning. Comp Aid Surg 5:175–179 (2000). © 2000 Wiley‐Liss, Inc.

Numerical simulation of normal nasal cavity airflow in Chinese adult: a computational flow dynamics model

“…A few CFD studies of the human nasal airflow were conducted. Most of these investigations were performed just with a single model [14][15][16][17][18][19]. A research with a larger sample for a profound understanding on the relationship between airflow and physiological nasal function was required.…”

Computational fluid dynamics modeling of the upper airway of children with obstructive sleep apnea syndrome in steady flow

“…Detailed studies are available of flow in adult nasal passages for analysis of aerosol deposition and rhinosurgery planning, using idealized geometry (Elad et al, 1993), medical training model geometry (Martonen et al, 2002), or anatomical geometry (Bockholt et al, 2000;Hahn et al, 1993;Keyhani et al, 1995). To study flow resistance in the adult, the pharyngeal airway has been modeled as an elliptical orifice to account for local area restriction (Leiter, 1992), or as a 3D conduit to study the effects of area variation and turbulence using computational fluid dynamics (CFD) (Shome et al, 1998).…”

Visualization of Flow Resistance in Physiological Nasal Respiration

“…[11][12][13][14][15][16][17][18][19][20] Moreover, most studies evaluated the nonphysiological steady flow condition. [11][12][13][14][15][16][17][18] The primary objectives of this study were (1) visualize the velocity gradients and the vorticities of physiological unsteady nasal flow using the CFD method and (2) to compare the flow patterns during the inspiratory and expiratory phases. To our knowledge, our study is the first trial to establish a computational model simulating the intranasal vorticity profiles during physiological nasal respiration.…”

“…Computational fluid dynamics (CFD) is a numerical simulation application that enables the visualization of flow factors (velocity, pressure, vector, streamline, and vorticity or [amount of vortex]) under various flow conditions. Many researchers have conducted CFD studies [11][12][13][14][15][16][17][18][19][20] of the human nasal airflow; however, most of these investigations did not focus on the factor of vorticity. In addition, their analyses were performed under almost a steady flow condition, which differs from that of physiological nasal respiration (an unsteady flow condition).…”