Introduction: The assessment of the volumetric changes of the airways after adenotonsillectomy has gained popularity among orthodontists, but the validity of such evaluation is not clear.
Methods: Thirty patients with obstructive sleep apnea diagnosed with the use of polysomnography (PSG) were evaluated according to the Apnea and Hypopnea Index (AHI), the obstructive apnea index (OAI), the oxygen desaturation index (ODI), the lowest oxygen saturation (LSpO), and the average oxygen saturation (ASpO). The volume and the minimal cross-section of lower (oropharynx and velopharynx) and upper (nasopharynx) spaces of the airways were calculated.