阻塞性睡眠呼吸暂停综合征的生物力学研究

Biomechanical Study of Obstructive Sleep Apnea Syndrome

利用CT扫描数据,建立一个由硬腭水平位置至气管约第2,3软骨下端的人体上气道三维有限元模型,采用睡眠呼吸暂停综合征(OSAS)事件发作期间上气道内典型压力曲线和最大压力曲线,分别对模型上气道表面施加动态载荷,分析解剖结构和生理过程之间的关系。计算结果表明在OSAS事件发作期,最易发生塌陷的部位是软腭后区,其次是舌后区和会厌后区;正常的上气道解剖结构在异常的压力作用下仍然可能发生狭窄和塌陷;OSAS事件发作期的呼吸过程中,软腭后区、舌后区、会厌后区等各个平面的前后径变化均大于左右径的变化;解剖结构异常不是OSAS发病的必要条件。

A 3D FE model of the human upper airway was established based on CT data, which included upper airway, partitive maxilla, mandible and hyoid. A set of dynamic loads, based on the pressure-time curves in the literature, were exerted on the upper airway. The simulation results reveal that velopharynx is the region that is most prone to collapse, when the obstruction of airflow happens. The lesser dangerous regions are oropharynx and hypopharynx. The upper airway with normal anatomic structure can collapse under abnormal loads. During the obstruetion of airflow, the variations of the sagittal diameters are larger than those of the transverse diameters in velopharynx, oropharynx and hypopharynx. Abnormal anatomic structure is not the necessary factor of OSAS （obstructive sleep apnea syndrome） event.