Analysis of Obstruction Site in Obstructive Sleep Apnea Patients Based on Videofluoroscopy

ABSTRACT

BACKGROUND AND OBJECTIVES: Upper airway obstruction can occur at the soft palate, tongue base, or epiglottis among obstructive sleep apnea (OSA) patients. Detection of these obstruction sites is very important for choosing a treatment modality for OSA. The purpose of this study was to evaluate the obstruction site of OSA patients and its association with mouth opening and head position. SUBJECTS AND METHOD: Forty-eight consecutive patients with suspicion of OSA were enrolled and underwent videofluoroscopy to evaluate the obstruction site, as well as polysomnography. Obstruction site, mouth opening, and head position were evaluated on videofluoroscopy, and their association was analyzed. RESULTS: According to the videofluoroscopy, 47 (97.9%) of 48 patients showed an obstruction in the soft palate, while 24 (50.0%) were located in the tongue base and 14 (29.2%) in the epiglottis. Multiple obstructions were observed in many patients. Mean apnea-hypopnea index was higher among patients with tongue base obstruction (42.3±26.7) compared to those without obstruction (26.4±21.2, p=0.058). However, epiglottis obstruction did not influence apnea-hypopnea index. Mouth opening did not show any association with tongue base obstruction (p=0.564), while head flexion was highly associated (p<0.001). CONCLUSION: Half of patients with OSA have tongue base obstruction, which worsens the apnea-hypopnea index. Head flexion is associated with tongue base obstruction, while mouth opening is not.