目的建立儿童阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome,OSAHS)上气道气流场数值模型,并应用其评价分析阻塞因素及平面。方法根据9例OSAHS患儿的上气道CT影像,对病态和模拟腺样体切除术后病例通过表面重建的方法进行三维重建,然后用有限元法对术前术后上气道气流进行数值模拟,分析气流流场特征。结果病态模型中,鼻咽部气流形态主要以湍流为主,术后模型中,以层流为主,上气道压强均降低。病态模型的鼻咽部、鼻阈和中鼻道是鼻腔气流高流速区,术后模型中鼻腔气流高流速区仅为鼻阈和中鼻道。结论数字化三维重建模型能应用于临床,并客观分析OSAHS患儿的阻塞因素和平面,为临床个体化诊断提供新的方法和客观理论依据。
Objective To establish the air flows field computer phantom models of children with obstructive sleep apnea-hypopnea syndrome(OSAHS),and carry out the models to analyse obstucion element and plane.Methods 3-dimensional structure and flow field models of the upper airway were reconstructed according the upper airway CT data of nine children with OSAHS.Then the air flow field characteristics of preoperative and postoperative in the upper airway by finite-element mesh were analysed and simulated.Results Turbulent flow was the main form in nasopharynx and the main centralized hight flow rate zone was nasopharynx,limen nasid and middle nasal meatus in the morbid model.Laminar flow was the main form and the flow rate grew down in nasopharynx and the pressure was reduced in upper airway in "after-adenoidectomy" models.Conclusion 3-dimensional structure and flow field model can be used in clinic and provide impersonal theory basis of obstucion element and plane for the children with OSAHS.It can provide new impersonal clinical diagnosis and impersonal theory basis.