Posterior cephalometric radiographic analysis in obstructive sleep apnea.

Our objective was to evaluate the relationship between posterior facial cephalometric measures and obstructive sleep apnea syndrome (OSAS). We used a consecutive sample of 60 patients with OSAS who underwent upright lateral cephalograms, uvulopalatopharyngoplasty (UPPP), and preoperative and postoperative polysomnography. Successful responders to UPPP were arbitrarily defined as having a respiratory disturbance index reduced to fewer than 20 events per hour. Standard cephalometric measurements were used. Posterior facial height measures were constructed, based on a plane perpendicular to the Frankfort horizontal placed at hyoidale. The total and lower airway lengths were shorter and posterior mandibular height was longer in UPPP responders compared to nonresponders (p < or = .05). There was no difference between the two groups by standard cephalometric measurements. Responders and nonresponders to UPPP have significant differences in posterior airway measures that are not reflected in standard cephalometric measures. Airway length likely is a critical factor in OSAS and surgical response.