Shumit Saha1,2,3, Zahra Moussavi1, Peyman Hadi4, T Douglas Bradley2,5, Azadeh Yadollahi2,3. 1. Department of Biomedical Engineering, University of Manitoba, Winnipeg, Manitoba, Canada. 2. Toronto Rehabilitation Institute-University Health Network, Toronto, Ontario, Canada. 3. Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada. 4. BresoTec Inc., Toronto, Ontario, Canada. 5. Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
Abstract
STUDY OBJECTIVES: Snoring sounds are generated by the vibration of pharyngeal tissue due to the upper airway narrowing. While recorded by a microphone placed over the neck, snoring can pass through the pharyngeal tissue surrounding the upper airway. Thus, changes in the pharyngeal tissue content may change the acoustic properties of the snoring sounds. Rostral fluid shift and the consequent increases in neck fluid volume (NFV) and neck circumference (NC) can increase pharyngeal tissue mass. Therefore, the goal of this study was to investigate the relationship between increases in pharyngeal tissue mass, as assessed by increased NFV and NC, and snoring sounds features. METHODS: We obtained data from a previous study where 20 males who were not obese participated in a daytime polysomnography and their NC and NFV were measured before and after sleep. During sleep, snoring sounds were recorded with a microphone placed over the neck. Spectral centroid of the snoring sounds was estimated. Then, the first five snoring segments were selected from the first and last 30 minutes of stage N2 sleep. RESULTS: We found a significant decrease in the snoring spectral centroid from the beginning to end of sleep. We also found that spectral centroid from the end of sleep in frequency ranges below 200 Hz was inversely correlated with the increases in NFV and NC from before to after sleep. CONCLUSIONS: These results suggest that snoring spectral centroid can be used as a noninvasive and convenient method to assess variations in the pharyngeal tissue mass.
STUDY OBJECTIVES: Snoring sounds are generated by the vibration of pharyngeal tissue due to the upper airway narrowing. While recorded by a microphone placed over the neck, snoring can pass through the pharyngeal tissue surrounding the upper airway. Thus, changes in the pharyngeal tissue content may change the acoustic properties of the snoring sounds. Rostral fluid shift and the consequent increases in neck fluid volume (NFV) and neck circumference (NC) can increase pharyngeal tissue mass. Therefore, the goal of this study was to investigate the relationship between increases in pharyngeal tissue mass, as assessed by increased NFV and NC, and snoring sounds features. METHODS: We obtained data from a previous study where 20 males who were not obese participated in a daytime polysomnography and their NC and NFV were measured before and after sleep. During sleep, snoring sounds were recorded with a microphone placed over the neck. Spectral centroid of the snoring sounds was estimated. Then, the first five snoring segments were selected from the first and last 30 minutes of stage N2 sleep. RESULTS: We found a significant decrease in the snoring spectral centroid from the beginning to end of sleep. We also found that spectral centroid from the end of sleep in frequency ranges below 200 Hz was inversely correlated with the increases in NFV and NC from before to after sleep. CONCLUSIONS: These results suggest that snoring spectral centroid can be used as a noninvasive and convenient method to assess variations in the pharyngeal tissue mass.
Authors: Takatoshi Kasai; Shveta S Motwani; Dai Yumino; Susanna Mak; Gary E Newton; T Douglas Bradley Journal: Circ Heart Fail Date: 2012-06-07 Impact factor: 8.790
Authors: Azadeh Yadollahi; Joseph M Gabriel; Laura H White; Luigi Taranto Montemurro; Takatoshi Kasai; T Douglas Bradley Journal: Sleep Date: 2014-10-01 Impact factor: 5.849