A method to describe the pharyngeal airway

Abstract

Objectives/hypothesis: To describe and to assess reproducibility of a method to model the lumen of the pharyngeal airway using anatomic structures.

Study design: Single-center, institutional review board-approved retrospective case series.

Methods: Multiple structural landmarks (hard palate, palatal aponeurosis, genu, velum, and lateral wall; pharyngeal and vallecular tongue base; and epiglottis) were used as reference points to score the associated airway. These characteristics were then combined to create a luminal model of the pharyngeal airway. Retrospective assessment by two independent observers of 117 sedated endoscopies from a convenience sample (81% male, aged 51.4 years; apnea hypopnea index 38.5 events/hr) was performed.

Results: Scoring of individual landmarks demonstrated a good or better agreement (kappa of 0.42-0.79). Agreement on whether the airway was constricted/obstructed was very high (kappa > 0.77). Based on differences in airway measures at different levels, multiple patterns of luminal shape and narrowing were observed. The upper pharyngeal lumen was classified into different shapes based on findings at different levels of the soft palate (oblique, 52%; intermediate, 23%; vertical, 25%). Similarly, the lower pharynx was classified into three shapes based on the structure of the tongue.

Conclusion: Multiple pharyngeal luminal configurations describing airway phenotypes can be described using landmarks identifiable on endoscopy.

Level of evidence: 4.

Keywords: DISE; Sleep apnea; airway phenotypes; endoscopy; examination; hypopharynx; obstructive sleep apnea; palate; pharynx; surgery; tongue; upper airway.