[Diagnosis of obstructive level in pharynx with obstructive sleep apnea hypopnea syndrome with multiple detector-row spiral CT].

OBJECTIVE:To evaluate the diagnostic significance of multiple detector-row spiral CT(MSCT) in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). METHOD:Sixty-seven patients with OSAHS and 40 volunteers were scanned. The CT imagings from the nasopharyngeal floor to the glottis obtained. The relevant dimensions of area, diameter, thickness of retropharyngeal tissue were measured in some regions in imagings including nasopharynx, oral pharynx and hypopharynx, as well as the narrowest region in pharynx. RESULT:1) The values of area, left-right diameter and front-back diameter of oral pharyngeal imagings of patients with OSAHS were narrowest regions which were (133.5 +/- 32. 9) mm2, (12.5 +/- 2.0) mm, (10.4 +/- 1.8) mm respectively. The value of above parameters of oral pharyngeal imagings of volunteers were (238.5 +/- 46.5) mm2, (20.4 +/- 3.1) mm, (21.1 +/- 4.0) mm respectively. The values of two groups had marked difference by statistics (P< 0.01). 2) The narrowest regions were located in oral pharynx in the imagings of 58 patients with OSAHS, which located in soft palate site in 19 patients, in oral pharynx site in 11 patients and in retro-lingua site in 28 patients. The narrowest regions were located in nasopharynx in the imagings of 3 patients. None of the narrowest region was found in hypopharynx. The narrowest regions, which all located in oral pharynx, were measured in the imagings of 24 volunteers. 3) The values of area, left-right and front-back diameter of the narrowest regions of imaging of 58 patients with OSAHS among 67 patients were (75.6 +/- 17.9) mm2, (10.6 +/- 2.1) mm, (6.9 +/- 1.0) mm respectively. The values of bove parameter of the most narrowest regions of imagings of volunteer were (187.3 +/- 35.6) mm2, (21.4 +/- 4.3) mm, (15.6 +/- 2.7) mm respectively. There were significant difference in statistics among the data of these groups (P < 0.01). CONCLUSION:The imagings of MSCT may provide accurate diagnosis in OSAHS. Patients with OSAHS always had anatomically narrow in pharynx, especially in oral pharynx.