Airway changes in obstructive sleep apnoea patients associated with a supine versus an upright position examined using cone beam computed tomography.

OBJECTIVE

This study aimed to describe total volume and cross-sectional area measurement changes in obstructive sleep apnoea patients associated with a supine versus an upright position.

METHOD: A retrospective chart review of patients who underwent cone beam computed tomography in upright and supine positions was performed, and the images were analysed.

RESULTS

Five obstructive sleep apnoea patients (all male) underwent both upright and supine cone beam computed tomography imaging. Mean age was 35.0 ± 9.3 years, mean body mass index was 28.1 ± 2.7 kg/m2 and mean apnoea-hypopnoea index was 39.3 ± 23.0 per hour. The airway was smaller when patients were in a supine compared with an upright position, as reflected by decreases in the following airway measurements: total volume; posterior nasal spine, uvula tip, retrolingual and tongue base (not significant) cross-sectional areas; and site of the minimum cross-sectional area (of the overall airway). Total airway volume decreased by 32.6 per cent and cross-sectional area measurements decreased between 32.3 and 75.9 per cent when patients were in a supine position.

CONCLUSION

In this case series, the airway of obstructive sleep apnoea patients was significantly smaller when patients were in a supine compared with an upright position.