Epiglottis cross‐sectional area diminishes with increased severity of obstructive sleep apnea (LB70)

Abstract

Obstructive sleep apnea (OSA) is a condition characterized by episodic upper airway collapse with continued diaphragmatic efforts during sleep. Significant cardiovascular and neurophysiological defects may result from brain injury accompanying repeated epochs of hypoxia. The majority of occlusions in OSA patients occur at the soft palate and uvula of the oropharynx. However, the extent of cross‐sectional area at the level of the epiglottis, between the oropharynx and hypopharynx, remains unclear. Morphological aspects at lower regions of the oropharynx, with different cranial nerve innervation from upper airway regions, may also contribute to obstruction. Using a 3.0 Tesla brain magnetic resonance imaging (MRI) scanner, we collected two high‐resolution T1‐weighted image series and measured axial cross‐sectional areas and oropharyngeal airway lengths for 13 mild or moderate OSA (mean age ± SD: 48.24 ± 8.28; AHI 5‐29.9 events/hr; 6 male), 11 severe OSA (48.81 ± 8.31; AHI 蠅 30 events/hr; 8 male) and 50 control subjects (47.17 ± 9.06; 28 male). Epiglottis cross‐sectional areas were significantly reduced in OSA over control subjects (p=0.005) and collapsible oropharyngeal airway lengths were significantly increased in OSA over control subjects (p <0.001). The diminished epiglottis cross‐sectional areas and increased airway lengths in OSA patients may contribute to a greater vulnerability for airway collapse.Supported by National Institutes of Health R01 HL‐113251.