The study of the upper airway in obstructive sleep apnea hypopnea syndrome with multi-slice spiral CT

Objective To retrospectively investigate the upper airway (UA) characteristics of the obstructive sleep apnea hypopnea syndrome (OSAHS) with multi-slice spiral computed tomography (MSCT), and to analyze the value of MSCT in the clinical diagnosis and pathogeny research of OSAHS. Methods The pharynxes of 28 cases with OSAHS and 14 controls were scanned by MSCT at the time of deep inspiration, deep expiration, normal respiration, and Muller action. The cross-section area with its corresponding sagittal and transverse diameters at naso-, velo-, and tongue-pharyngeal level, the length and thickness of soft palate, the site and range of UA obstruction, and the pharyngeal collapsibility were measured and calculated, respective. Results (1)MSCT with its software package could ideally and accurately help to observe the UA, measure the required data, and judge the range of UA obstruction. (2)Mean cross-section areas of velo-pharynx and tongue-pharynx in OSAHS were significantly less than those in the control group, which mostly occurred at the end of deep inspiration(P0.05). (3)The collapsibilities at the velo-pharyngeal and tongue-pharyngeal levels in OSAHS were higher than those in the control group ((F=15.133,) P=0.001; F=5.552, P=0.025). (4)The soft palates of OSAHS were thicker than those in the controls (F=15.908, P=0.000). Conclusions The straitness and the larger collapsibility at the velo-pharynx and tongue-pharynx are perhaps the main causes of OSAHS. MSCT is relatively convenient, quick, and accurate in the observation of the UA, thus possessing the practical value in the clinical diagnosis and pathogeny research of OSAHS.