Awake endoscopic assessment of the upper airway during tidal breathing: Definition of anatomical features and comparison with drug-induced sleep endoscopy.

Objectives: Awake nasopharyngoscopy is routinely performed in the assessment of patients who require treatment for sleep-disordered breathing (SDB). However, the applicability and accuracy of Müller's manoeuvre, the main evaluation method for this purpose, are disputable. The current study aimed to introduce an alternative method for awake nasopharyngoscopy in patients with SDB.

Design: We defined qualitative anatomical features during tidal breathing at the levels of the soft palate, oropharynx, tongue base, epiglottis and hypopharynx, and compared these awake features to the sites and patterns of collapse as observed during drug-induced sleep endoscopy (DISE).

Setting: Tertiary care academic centre.

Participants: Seventy-three patients diagnosed with SDB.

Main Outcome Measures: The primary outcome measure was the Kendall's tau correlation coefficient (τ) between observations during awake nasopharyngoscopy and DISE. Kappa-statistics (κ) were calculated to assess the agreement on awake endoscopic features with a second observer.

Results: In contrast to epiglottis shape, the modified Cormack-Lehane scale was significantly associated with epiglottis collapse during DISE (P < .0001; τ = .45). Other upper airway features that were correlated with DISE collapse were the position of the soft palate (P = .007; τ = .29), crowding of the oropharynx (P = .026; τ = .32) and a posteriorly located tongue base (P = .046; τ = .32). Interobserver agreement of endoscopic features during tidal breathing was moderate (0.60 ≤ κ < 0.80).

Conclusion: The current study introduces a comprehensive and reliable assessment method for awake nasopharyngoscopy based on anatomical features that are compatible with DISE collapse patterns.