Mechanical parameters determining pharyngeal collapsibility in patients with sleep apnea.

The relative impact of mechanical factors on pharyngeal patency in patients with obstructive sleep apnea is poorly understood. The present study was designed to evaluate parameters of the "tube law" on pharyngeal pressure-flow relationships and collapsibility in patients with obstructive sleep apnea. We developed a mathematical model that considered the collapsible segment of the pharynx to represent an orifice of varying diameter.