[The evaluation of severity and treatment for OSAHS by acoustic pharyngometry which in different postures]

Objective: To investigate the optimal position in application of acoustic pharyngometry to detect the pharyngeal condition and to assess its therapeutic effect on obstructive sleep apnea hypopnea syndrome(OSAHS). Method: Eight adult males were assigned to the normal group, and 57 male patients with OSAHS diagnosed by polysomnograhy(PSG) were assigned to the snoring group. Of the snoring group, 11 patients who were diagnosed severe OSAHS underwent low-temperature plasma uvulopaltopharyngoplasty(UPPP) and coblationchanneling of the tongue(CCT), were assigned to the operation subgroup; 8 patients underwent continuous positive airway pressure(CPAP), which was assigned to the CPAP subgroup. And remainders underwent conservative treatment, including weight loss and position change. Acoustic pharyngometry (three positions including sitting position, supine position and lateral position) and PSG exam were performed in all participants. Additionally, acoustic pharyngometry under three positions was conducted again in patients in the operation and CPAP subgroups three months after treatment. Result: The minimum cross-sectional area was negatively associated with both AHI and the percentage of time with oxygen saturation below 90%(SIT90)( P<0.01). The correlation coefficient of the minimum crosssectional area insupine position with AHI and SIT90 were r=-0.569,r=-0.478, respectively. Under supine position, the minimum crosssectional area was negatively correlated with body mass index(BMI)(r=-0.265, P=0.033), and the minimum crosssectional area was negatively associated with neck circumference(r=-0.309, P=0.012). The minimum cross-sectional area was significantly increased after treatment of OSAHS(both operation and CPAP), which was statistically different before and after treatment compared to the control group(P<0.01). Conclusion: ①The minimum cross-sectional area is significantly correlated with AHI and SIT90, respectively. The acoustic pharyngometry can be used to screen OSAHS patients. ②In this study, the minimum cross-sectional area under supine position is significantly smaller than that under sitting position. In addition, the minimum cross-sectional area under supine position harbored a better correlation with AHI and SIT90, which could better reflect the narrowness of pharyngeal cavity during sleep. ③Acoustic pharyngometry could be a simple, rapid and non-invasive technique that can objectively evaluate the efficacy of surgical and CPAP methods, and provided a more favorable basis for future clinical work..