Background: A large percentage of the population suffers from obstructive sleep apnea (OSA). Obesity, anomalies in the anatomy of the upper airway, and hormonal impacts are all factors that can predict the occurrence of OSA. This work aimed to describe the different levels and patterns of collapse during nasopharyngoscopy (Muller's Maneuver) among patients who had obstructive sleep apnea.

Methods: This cross-sectional research involved 62 cases diagnosed as obstructive sleep apnea underwent Fibro-optic nasopharyngoscopy in the phoniatric unit, ENT department, faculty of medicine, Zagazig University, from August 2023 until August 2024.

Results: Apnea hypopnea index ranged from 5.3 to 110 with mean 33.75. Minimum oxygen saturation ranged from 40 to 93% with mean 76.31%. The commonest pattern of retropalatal closure was concentric in 59.7%, while 66.1% of patients had lateral obstruction in retro-laryngeal part and 61.3% of -patients had no closures in hypopharyngeal part. Mean grade of closure of retro-palatal and retro-laryngeal part were 76.05% and 67.74% respectively. Median grade of closure of hypopharyngeal part was 0%.

Conclusion: Muller's Maneuver could be crucial in identifying the level, pattern, and grade of upper airway obstruction which serves in the plan of management and type of surgery.