MSCT in patients with obstructive sleep apnea hypopnea syndrome

Objective:To assess the diagnostic value of MSCT with multi-respiratory phase scanning and post-processing techniques of the upper airway in obstructive sleep apnea hypopnea syndrome(OSAHS).Methods:The upper airway of 68 cases with OSAHS and 65 healthy volunteers as controls in supine position was scanned with MSCT in four respiratory phases:regular respiration,deep inspiration,deep expiration,and Muller action while they were awake.The anteroposterior diameter,transverse diameter,cross-sectional area at nasopharyngeal,velopharyngeal,glossopharyngeal and epiglottis area,the length and thickness of soft palate and the thickness of nasopharynx top wall were measured in different respiratory phases.The shape of upper airway was demonstrated by CT virtual bronchoscopy(VE).Results:The length and thickness of soft palate,the thickness of nasopharynx top wall in OSAHS were all larger than the controls.The anteroposterior diameter,transverse diameter,cross-sectional area at nasopharyngeal,velopharyngeal,and glossopharyngeal area in OSAHS were smaller than the controls,and the velopharyngeal area was the smallest while the glossopharyngeal area was the second small.The upper airway lost its transverse elliptic structure in OSAHS.The upper airway in OSAHS had complete multi-site obstructions in multi-respiratory phase.The pharyngeal cavity demonstrated significant narrowing or even complete obstruction in virtual endoscopy(VE).Conclusion:MSCT with multi-respiratory phase scanning and post-processing techniques of upper airway can accurately evaluate the extent and degree of pharyngeal stenosis in OSAHS patients and play an important role for clinical treatment.