Phenotypes of Velopharyngeal Tube Law in Obstructive Sleep Apnea

Authors

• Devesh Kumar, Medical College of Wisconsin
• B. Tucker Woodson, Medical College of Wisconsin
• Guilherme J.M. Garcia, Marquette University

Document Type

Article

Publication Date

10-2024

Publisher

SAGE Publications

Source Publication

Otolaryngology-Head and Neck Surgery

Source ISSN

0194-5998

Original Item ID

DOI: 10.1002/ohn.997

Abstract

Objective

The biomechanics of upper airway collapse in obstructive sleep apnea (OSA) remains poorly understood. The goal of this study is to compare the area-pressure relationship (tube law) of the velopharynx at peak inspiration and peak expiration.

Study Design

Cross-sectional.

Setting

Academic tertiary medical center.

Methods

The velopharyngeal tube law was quantified in a convenience sample of 20 OSA patients via step reductions in nasal mask pressure during drug induced sleep endoscopy (DISE). The velopharyngeal airspace cross-sectional area was estimated from endoscopy while luminal pressure was recorded with a catheter. The tube law was quantified for nasal mask pressures from 14 to 0 cmH2O at peak inspiration and at peak expiration in all patients. The tube law was also quantified during the breathing cycle at a constant nasal mask pressure of 4 cmH2O in 3 patients representing different phenotypes.

Results

Velopharyngeal compliance (the slope of the tube law) was not statistically different in the peak inspiration versus peak expiration tube laws. Three phenotypes were observed, namely inspiratory collapse (phenotype 1), expiratory collapse (phenotype 2 = palatal prolapse), and a mostly stable airway during inspiration and expiration that collapsed as CPAP was reduced (phenotype 3).

Conclusion

Velopharyngeal compliance is not significantly different at peak inspiration and peak expiration, which suggests that muscle tone is low when luminal pressure is above the closing pressure. Additional studies are needed to investigate how different phenotypes of velopharyngeal collapse may affect therapeutic outcomes.

Comments

Otolaryngology-Head and Neck Surgery, Vol. 172 (2024, October): 336-245. DOI.

Recommended Citation

Kumar, Devesh; Woodson, B. Tucker; and Garcia, Guilherme J.M., "Phenotypes of Velopharyngeal Tube Law in Obstructive Sleep Apnea" (2024). Biomedical Engineering Faculty Research and Publications. 726.
https://epublications.marquette.edu/bioengin_fac/726