148 J Sleep Sci, Vol. 1, No. 4, 2016 http://jss.tums.ac.ir Original Research Muller’s Maneuver in Patients with Obstructive Sleep Apnea Amin Amali 1 , Behrooz Amirzargar 2 *, Mohammad Sadeghi 2 , Babak Saedi 2 1. Otorhinolaryngology Research Center AND Department of Otolaryngology, Head and Neck Surgery, School of Medi- cine AND Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran 2. Otorhinolaryngology Research Center AND Department of Otolaryngology, Head and Neck Surgery, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Received: 15 Sep. 2016 Accepted: 15 Nov. 2016 Abstract Background and Objective: Numerous anatomical abnormalities or pathological conditions can cause upper airway ob- struction in obstructive sleep apnea syndrome (OSAS). Muller’s maneuver (MM) is one of diagnostic modalities investigating the obstruction site in patients with OSAS. This study aimed to investigate the obstruction sites of patients with OSAS based on MM. Materials and Methods: This was a case-series study. A total of 145 patients were enrolled in this study. The awake MM (a flexible fiberoptic endoscopy of the upper airway while patients perform forced inspiration against a closed oral and nasal airway) was performed by a single surgeon with the patient in a supine position. Endoscopic findings were clas- sified using the modified velum, oropharyngeal lateral walls, tongue base, and epiglottis (VOTE) classification criteria. Results: Mean ± standard deviation age of patients was 41.5 ± 10.1 years old. Mean respiratory disturbance index was 29.7 ± 24.3/hours. The most common site of obstruction in all patients was velum. About 72% of the patients had more than 75% obstruction in the velum area while most patients had < 50% obstruction in oropharyngeal lateral walls (41.4%) and tongue base (55.2%). 69% of the patients had no obstruction in epiglottis according to the modified VOTE classification. Conclusion: Simple awake diagnostic test before surgery would help physicians to identify obstruction sites of OSAS patients. © 2016 Tehran University of Medical Sciences. All rights reserved. Keywords: Muller’s maneuver; Obstructive sleep apnea syndrome; Velum, Oropharyngeal lateral walls, Tongue base, Epiglottis Citation: Amali A, Amirzargar B, Sadeghi M, Saedi B. Muller’s Maneuver in Patients with Obstructive Sleep Apnea. J Sleep Sci 2016; 1(4): 148-50. Introduction 1 As the rate of obesity and immobility increased during recent decades, the prevalence of the ob- structive sleep apnea syndrome (OSAS) increased as well. OSAS as a sleep-related breathing disor- der is characterized by repetitive episodes of ob- struction of the upper airway during sleep, and is also associated with several cardiovascular and neurocognitive consequences (1-3). Although snoring occurs in 40% of men and 20% of women, the literature report that 4% of men and 2% of women above the age of 50 years, experience symptomatic sleep apnea (4). OSAS is * Corresponding author: B. Amirzargar, Otorhinolaryngology Research Center, Tehran University of Medical Sciences, Tehran, Iran Tel: +989124886343, Fax: +982166581628 Email: amirzargarb@yahoo.com usually diagnosed by the history and physical ex- amination and confirmed by the polysomnography. Numerous anatomical abnormalities or patho- logical conditions can cause upper airway obstruc- tion such as septal deviation, turbinate hypertrophy, nasal polyposis, adenoid hypertrophy, palatine ton- sil or lingual tonsil hypertrophy, tongue hypertro- phy, epiglottis deformity, and tumors (5, 6). Proper surgical or medical management of the OSAS depends on the identification of the level(s) of upper airway obstruction in patients. The most common surgical procedure for patients with OSAS is uvulopalatopharyngoplasty (UPPP). Un- less correct identification of the obstructed site the surgery would not improve clinical signs and symptoms. In other words, UPPP would be highly beneficial for patients with mere retropalatal ob- struction; while it is much less helpful to patients