This paper is only available as a PDF. To read, Please Download here.
Abstract
The aim of this study was to examine a new technique based on sound reflections in a flexible tube for identifying obstructive sites of the upper airway during sleep. There was no significant difference between two nights in seven obstructive sleep apnoea (OSA) patients regarding the level distribution of pharyngeal narrowings, when the pharynx was divided into two segments (retropalatal and retrolingual). We also compared the level distribution determined by magnetic resonance imaging (MRI) with the level distribution found by flextube reflectometry in seven OSA patients. There was no significant difference between flextube and MRI level distributions during obstructive events, but due to few subjects the power of the test was limited. We found a statistically significant correlation between the number of flextube narrowings per hour of sleep and the number of obstructive apnoeas and hypopnoeas per hour of sleep determined by polysomnography (PSG) in 21 subjects (Spearman's correlation coefficient r=0·79, P<0·001). In conclusion, the flextube reflectometry system seems to be useful for level diagnosis in OSA before and after treatment.
Keywords
References
REFERENCES
- Surgery for obstructive sleep apnoea (Cochrane Review). The Cochrane Library, Oxford2001 (p. 2)
- The efficacy of surgical modifications of the upper airway in adults with obstructive sleep apnea syndrome.Sleep. l996; 19: 156-177
- Palate and hypopharynx—sites of inspiratory narrowing of the upper airway during sleep.Am Rev Respir Dis. 1998; 138: 1542-1547
- Variable site of airway narrowing among obstructive sleep apnea patients.J Appl Physiol. 1986; 61: 1403-1409
- Determining the site of airway collapse in obstructive sleep apnea with airway pressure monitoring.Laryngoscope. 1993; 103: 1126-1131
- Continuous pressure measurements in the pharynx and esophagus during sleep in patients with obstructive sleep apnea syndrome.Laryngoscope. 1992; 102: 1275-1280
- Diagnostic airway pressure recording in sleep apnea syndrome.Acta Otolaryngol Stockh. 1995; 115: 449-454
- Sleep nasendoscopy: a technique of assessment in snoring and obstructive sleep apnoea.Clin Otolaryngol. 1991; 16: 504-509
- Fluoroscopic MR of the pharynx in patients with obstructive sleep apnea.Am J Neuroradiol. 1998; 19: 1205-1214
- Ultra-low-field magnetic resonance imaging in upper airways obstruction in sleep apnea syndrome.Psych Clin Neurosci. 1996; 50: 285-289
- Determination of obstructive site in obstructive sleep apnea.Laryngoscope. 1987; 97: 301-308
- The sites of obstruction in OSA, identified by continuous measurements of airway pressure and flow during sleep: ambulatory versus in-hospital recordings.Clin Otolaryngol. 1999; 24: 502-506
- Flextube reflectometry for localization of upper airway narrowing—a preliminary study in models and awake subjects.Respir Med. 2001;
Rechtscaffen, A, Kales, A, A manual of standardized terminology: techniques and scoring systems for sleep stages of human subjects, Los Angeles, Brain Information Service/Brain Research Institute, UCLA, 204, NIH Publication
- Reproducibility and accuracy of airway area by acoustic reflection.J Appl Physiol. 1984; 57: 777-787
- Tracheal stenosis measured by the acoustic reflection technique.Am Rev Respir Dis. 1984; 130: 472-475
- Airway geometry by analysis of acoustic pulse response measurements.J Appl Physiol. 1977; 43: 523-536
- Tracheal cross-sectional areas from acoustic reflections in dogs.J Appl Physiol. 1984; 57: 351-353
- Acoustic rhinometry: evaluation of nasal cavity geometry by acoustic reflection.J Appl Physiol. 1989; 66: 295-303
- Nasal airway geometry: comparison between acoustic reflections and magnetic resonance scanning.J Appl Physiol. 1993; 75: 2811-2819
- Technical abilities and limitations of acoustic rhinometry optimised for infants.Rhinology. 1998; 36: 104-113
- Automated detection and classification of sleep-disordered breathing from conventional polysomnography data.Sleep. 1997; 20: 991-1001
- Effect of sleep position and sleep stage on the collapsibility of the upper airways in patients with sleep apnea.Sleep. 2001; 24: 90-95
- Site of upper airway obstruction in obstructive apnoea and influence of sleep stage.Eur Respir J. 1997; 10: 2566-2572
- Sleep apnea syndrome. Examination of pharyngeal obstruction with high-speed MR and polysomnography.Acta Radiol. 1996; 37: 315-320
- Evaluation of the pharyngeal airway in obstructive sleep apnea: study by ultrafast MR imaging.Acta Otolaryngol. 1996; 523: 242-244
- Nocturnal polysomnography with and without continuous pharyngeal and esophageal pressure measurements.Sleep. 1996; 19: 485-490
- Effects of esophageal pressure monitoring on sleep architecture.Am J Respir Crit Care Med. 1997; 156: 881-885
- Pressure recordings—a method for detecting site of upper airway obstruction in sleep apnea syndrome.Acta Otolaryngol. 1992; 492: 132-140
Article info
Publication history
Accepted:
May 4,
2001
Received:
April 25,
2001
Identification
Copyright
© 2001 Harcourt Publishers Ltd. Published by Elsevier Inc.
User license
Elsevier user license | How you can reuse 
Elsevier's open access license policy
Elsevier user license
Permitted
For non-commercial purposes:
- Read, print & download
- Text & data mine
- Translate the article
Not Permitted
- Reuse portions or extracts from the article in other works
- Redistribute or republish the final article
- Sell or re-use for commercial purposes
Elsevier's open access license policy
