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Updated: May 19, 2026

Drug-Induced Sleep Endoscopy (DISE) with Target Controlled Infusion (TCI) and Bispectral Analysis in Obstructive Sleep Apnea
Published on: December 6, 2016
Flow oscillation - a measure to predict the surgery outcome for obstructed sleep apnea (OSA) subject
Yang Liu1, Jingying Ye, Zhengang Liu
1Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong. yang.liu@polyu.edu.hk
Abstract:
Obstructed sleep apnea (OSA) is a common disorder which may need surgery to widen the airway; however the success rate of surgery is limited. Here we report a finding that could be used to predict the outcome of the OSA surgery. We found that inspiratory flow oscillates due to flow separation near the larynx, and the resulting periodic signal (3-5Hz) is an intrinsic property of breathing. This flow oscillating signal may be the afferent stimulus to trigger respiratory events. It is found that the flow oscillation is attenuated for the OSA subjects. The computational fluid dynamics (CFD) simulation reveals that there exists flow separation near larynx and this separation is severely weakened in the OSA upper airway model. It is believed that the flow oscillating signal can serve as the measure to quantify the breathing quality of an OSA subject. This makes it possible to predict the surgery outcome of the OSA subject by applying CFD simulation.
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