Article

Properties of tissues surrounding the upper airway.

Department of Medicine, University of Pennsylvania Medical Center, Philadelphia 19104-4283, USA.
Sleep (impact factor: 5.05). 01/1997; 19(10 Suppl):S170-4. pp.S170-4
Source: PubMed

ABSTRACT The pathogenesis of obstructive sleep apnea (OSA) remains unknown. However, we are beginning to understand the mechanisms leading to sleep apnea by evaluating the structure and function of the upper airway (UA) and the surrounding soft-tissue structures using sophisticated magnetic-resonance-imaging techniques. Knowledge of the morphology and mechanical behavior of the soft-tissue structures is essential for a complete understanding of the physiology of the UA. Although the tongue and soft palate have been considered the most important UA soft-tissue structures, our data have highlighted the importance of the lateral pharyngeal walls in the mediating UA caliber. We have demonstrated that: (1) during wakefulness, the predominant anatomic abnormality underlying UA narrowing in patients with OSA is thickening of the lateral pharyngeal walls; (2) during respiration, there are significant changes in lateral airway dimensions as well as in the thickness of the lateral walls; and (3) incremental levels of continuous positive airway pressure (CPAP) result in progressive thinning of the lateral pharyngeal walls. The dynamic biomechanical behavior of the lateral pharyngeal walls during wakefulness, sleep, and during apneas needs to be investigated.

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Keywords

apnea
 
apneas
 
continuous positive airway pressure
 
dynamic biomechanical behavior
 
lateral airway dimensions
 
lateral pharyngeal walls
 
lateral walls
 
mechanical behavior
 
mediating UA caliber
 
OSA
 
pathogenesis
 
predominant anatomic abnormality
 
soft-tissue structures
 
sophisticated magnetic-resonance-imaging techniques
 
surrounding soft-tissue structures
 
UA
 
UA narrowing
 
UA soft-tissue structures
 
upper airway
 
wakefulness
 

R J Schwab