Comparison of cone-beam CT parameters and sleep questionnaires in sleep apnea patients and control subjects

The aim of this work was to compare the cone-beam computerized tomography (CBCT) scan measurements between patients with obstructive sleep apnea (OSA) and snorers to develop a prediction model for OSA based on CBCT imaging and the Berlin questionnaire.

Eighty subjects (46 OSA patients with apnea-hypoapnea index [AHI] >or= 10 and 34 snorers with AHI <10 based on ambulatory somnographic assessment) were recruited through flyers and mail at the University of Southern California School of Dentistry and at a private practice. Each patient answered the Berlin questionnaire, and was imaged with CBCT in supine position. Linear and volumetric measurements of the upper airway were performed by one blinded operator, and multivariate logistic regression analysis was used to identify risk factors for OSA.

The OSA patients were predominantly male and older and had a larger neck size and larger body mass index than the snorers. The minimum cross-sectional area of the upper airway and its lateral dimension were significantly smaller in the OSA patients. Airway uniformity defined as the minimum cross-sectional area divided by the average area was significantly smaller in the OSA patients.

Age >57 years, male gender, "high risk" on the Berlin questionnaire, and narrow upper airway lateral dimension (<17 mm) were identified as significant risk factors for OSA. The results of this study indicate that 3-dimensional CBCT airway analysis could be used as a tool to assess the presence and severity of OSA. The presence and severity (as measured by the respiratory disturbance index) of OSA is associated with a narrow lateral dimension of the airway, increasing age, male gender, and high-risk Berlin questionnaire.