CT measurement of upper airway on obstructive sleep apnea syndrome

Objective To investigate the characteristics of upper airway and to offer reference for clicnic treatment of OSAHS patients through observing the upper airway caliber and the corresponding pharyngeal wall by spiral computed tomography.Methods The upper airway of 107 patients with OSAHS confirmed by polysomnography and 42 normal controls was detected and compared.The upper airway,from the roof of nasopharynx to the inferior border of cricoid cartilage,was scanned by spiral CT.The coronary and arrowy diameters,the cross-section areas and the thickness of the pharyngeal wall at the levels of retropalate,uvula,lingua,and epiglottis regions were measured respectively with the image handling workstation.Results The cross-section areas of upper airway of OSAHS were smaller than those of the controls.The cross-section areas decreased and the thickness of pharyngeal walls increased along with the increase of severity of OSAHS.The thickness of lateral pharyngeal wall was positively related with the apnea hypopnea index(AHI).The cross-sectional areas of retropalatal region and retroglossal region of OSAHS patients were negatively correlated with the AHI and the neck circumference respectively.Conclusion The measurement of upper airway by spiral CT can observe the changes of pharyngeal aeras which are useful to judge the narrow level and degree of upper airway in OSAHS.