Obstruction Identification in a Compliant Tube with Application to Airway Passages

Abstract

Using the acoustic input impedance, an appropriate theoretical technique for identifying constrictions in a tube with wall inertance and elastance being considered is developed. Although the technique could work for various types of tubes, it is applied to identifying occlusion in an upper airway passage. The frequency spectrum of the input impedance is examined for three types of constrictions, namely localized, uniform and gradual models. The result demonstrates that the input impedance resonant frequencies can map the location, severity and degree of the constriction.