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Updated: Jul 7, 2026

Drug-Induced Sleep Endoscopy (DISE) with Target Controlled Infusion (TCI) and Bispectral Analysis in Obstructive Sleep Apnea
Published on: December 6, 2016
The correlation between pharyngeal narrowing and the severity of sleep-disordered breathing
Hyo Yeol Kim1, Kwon Hyo Bok, Hun-Jong Dhong
1Department of Otorhinolaryngology-Head and Neck Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Objective:
The aim of this study was to examine the correlation between the degree or shape of pharyngeal narrowing as observed during the Muller maneuver and the severity of sleep-disordered breathing (SDB).
Subjects And Methods:
We enrolled 33 patients with SDB, and they underwent polysomnography (PSG). The degree of pharyngeal narrowing (grade I-IV) according to fiberoptic nasopharyngoscopy with the Muller maneuver (FNMM) and the shape of pharyngeal narrowing were evaluated at different anatomical levels. These variables were compared with the total apnea hypopnea index (AHI), the supine AHI, and the lateral AHI obtained by PSG.
Results:
The retroglossal FNMM grades revealed significant correlation with total AHI (P = 0.030) and supine AHI (P = 0.012). The retropalatal FNMM grades were significantly correlated with lateral AHI (P = 0.020). The lateral-narrowing type at the retropalatal level is more significantly associated with higher total AHI compared with the anteroposterior-narrowing type (P = 0.010).
Conclusion:
The anatomic level and the degree of pharyngeal narrowing observed during FNMM revealed a correlation with the AHIs of different sleeping positions.
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