Polysomnographic Findings Versus Degree of Obstruction During Drug-Induced Sleep Endoscopy and Muller's Maneuver.

Purpose: To investigate associations between polysomnographic findings and the severity of upper airway obstructions during Muller's Maneuver (MM) and Drug-Induced Sleep Endoscopy (DISE) in patients with obstructive sleep apnea syndrome (OSAS).

Methods: This was a prospective cohort study. Adult patients newly diagnosed with OSAS in a tertiary sleep center were included consecutively and evaluated by polysomnography and MM. They then underwent DISE in an operating room. The associations between polysomnographic findings and the severity of upper airway obstructions during MM and DISE were assessed. Also, the degree and pattern of obstructions were compared using a modified VOTE questionnaire.

Results: 145 patients (mean age 41.5 ± 10.1 years) were enrolled. There were no associations between Respiratory Disturbance Index (RDI), mean and lowest O₂ saturation, and body mass index on the one hand, and obstruction degree in MM and DISE (p > 0.05). However, a significant positive correlation was observed between RDI and total VOTE scores in DISE and MM (r = 0.179, p = 0.031 and r = 0.221, p = 0.008 respectively). There were no differences between MM and DISE in diagnosing the degree of obstruction in the velum area (p = 0.687) and the epiglottis (p = 0.50). However, a significant difference was observed between the two techniques in the oropharynx lateral wall (p < 0.001) and tongue base (p = 0.017).

Conclusion: Although there was no association between polysomnographic findings and the severity of obstruction in MM and DISE for the separate levels of the upper airway, obstruction severity may be assessed more accurately by total VOTE score, which is representative of RDI severity.