Transversely Retropalatal Collapsibility Measured by Regular Endoscopy Is Associated with Position Independency and Apnea-Hypopnea Index

Abstract

Objectives:

Investigate whether the retropalatal airway collapsibility defined by regular endoscopy with Müller’s maneuver could be used for predicting position independency and apnea-hypopnea index (AHI) in patients with obstructive sleep apnea (OSA).

Methods:

This was a retrospective study and a total of 77 polysomnographies (mean AHI = 25.75 ± 22.69) and 77 awake endoscopies with Müller’s maneuver between January 2010 and October 2013 were reviewed from 45 OSA patients (40 men and 5 women; mean age, 40.7 ± 1.6 years). Transverse/longitudinal diameters and collapsibilities of the airway at the level of the uvular base were measured using a picture archiving and communication system. Intra- and interrater reliabilities were assessed. Associations among the retropalatal airway dimensions, AHI (total, supine, and lateral), and position independency (defined as a supine AHI of <2 times of the lateral AHI) were statistically analyzed.

Results:

Measurement of transverse diameters and transverse/longitudinal collapsibilities was highly reliable within and between raters (all intraclass correlation coefficients >0.8) but longitudinal diameters measurement was less reliable. Transverse collapsibility significantly correlated with position independency (r = 0.545, P = .019). It was also independently significantly associated with total (beta = 0.522, P < .001), supine (beta = 0.480, P = .001), and lateral (beta = 0.412, P = .006) AHI after multiple linear regression.

Conclusions:

Regular endoscopy with Müller’s maneuver continues to be an important clinical tool to evaluate the upper airway among OSA patients and a high transversely retropalatal collapsibility is a hallmark of non-positional and/or severe OSA.