The upper airway imaging characteristics and site investigation of obstructive sleep apnea-hypopnea syndrome patients with virtual endoscopy through spiral CT

Objective To investigate the characteristics of upper airway (UA) obstructive sites of obstructive sleep apnea-hyponea syndrome (OSAHS) patients by upper airway multiplate volume reconstruction (MPVR) with virtual endoscopy (VE) technique. Methods 32 patients were divided into 2 groups, i.e. OSAHS group 25 patients (according to PSG, severe in 13, moderate in 7 and mild in 5) and control group 7 subjects without habitual snoring. Axial CT (light speed XQ) of the upper airway (UA) during awake was carried out in both groups. The images of various sites of upper airway under different conditions had been reconstructed (MPVR) with measurement. Meanwhile, the obstructive sites in noso-, oro- and hypopharynx were found by upper airway VE.Results In 25 patients, 15 patients had airway closure at retropalatal region, the 2 of 15 also showed closure at RP and RG and another had airway closure from RP to hyoid site. Mean cross-sectional areas during muller maneuver was larger than those at the end of the inspiration therefore without further conspicuous stenosis.Conclusion The upper airway MPVR with spiral CT as virtual endoscopy, can reveal accurately the obstructive sites and characteristics in the OSAHS patients.