Effect Assessment of Airflow Resistance by Local Airway Stenosis with 3D Printing Airway Model

Abstract

Clinically noticing airway constriction can randomly cause small airway quickly closed and the surrouding airway occlusion happens subsequently. A phenomenon may happened called "avalanche phenomenon" inside airway [1]. But few study on how local airway stenosis affects the respiratory flow. Because the real local airway stenosis and its flow are still unable to be directly observed and measured. In this paper, narrow numerical model of the main and branched airway are established based on CT data of normal human airways. Then the trachea and bronchial branched airway constriction models are printed out on the 3D printer by PLA material. Finally, to measure airflow impedance of different airway models and analyze the impact of structural changes in the airway (shrink and narrow) airway impedance, we adopt independent research and development Forced Oscillation Technique(FOT). The test results preliminary show that the trachea stenosis has big effect on the airway viscous resistance (Rrs) and the elastic resistance (Xrs). The bronchial stenosis obviously increases the airway elastic resistance. This article provides a new method for the study on how local constriction affects the airflow inside airway in the future.