Liu Hongliang, Moxness Mads Henrik Strand, Prot Victorien Emile, Skallerud Bjørn Helge
Biomechanics Division, Department of Structural Engineering, The Norwegian University of Science and Technology, NTNU, NO-7491 Trondheim, Norway.
Department of Otolaryngology, Aleris Hospital and the Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway.
J Biomech. 2018 Jan 3;66:86-94. doi: 10.1016/j.jbiomech.2017.11.006. Epub 2017 Nov 10.
Obstructive sleep apnea (OSA) affects a large percentage of the population and is increasingly recognized as a major global health problem. One surgical procedure for OSA is to implant polyethylene (PET) material into the soft palate, but its efficacy remains to be discussed. In this study, we provide input to this topic based on numerical simulations. Three 3 dimensional (3D) soft palate finite element models including mouth-close and mouth-open cases were created based on three patient-specific computed tomography (CT) images. A simplified material modeling approach with the Neo-Hookean material model was applied, and nonlinear geometry was accounted for. Young's modulus for the implant material was obtained from uniaxial tests, and the PET implant pillars were inserted to the 3D soft palate model. With the finite element model, we designed different surgical schemes and investigated their efficacy with respect to avoiding the soft palate collapse. Several pillar schemes were tested, including different placement directions, different placement positions, different settings for the radius and the array parameters of the implant pillars, and different Young's moduli for the pillars. Based on our simulation results, the longitudinal-direction implant surgery improved the stiffness of the soft palate to a small degree, and implanting in the transverse direction was evaluated to be a good choice for improving the existing surgical scheme. In addition, the Young's modulus of the polyethylene material implants has an influence on the reinforcement efficacy of the soft palate.
阻塞性睡眠呼吸暂停（OSA）影响着很大一部分人群，并且越来越被视为一个重大的全球健康问题。一种针对OSA的外科手术是将聚乙烯（PET）材料植入软腭，但它的疗效仍有待探讨。在本研究中，我们基于数值模拟为该主题提供参考。根据三位患者的特定计算机断层扫描（CT）图像创建了三个三维（3D）软腭有限元模型，包括闭口和开口情况。应用了采用新胡克材料模型的简化材料建模方法，并考虑了非线性几何形状。植入材料的杨氏模量通过单轴试验获得，并且将PET植入柱插入到3D软腭模型中。利用有限元模型，我们设计了不同的手术方案，并研究了它们在避免软腭塌陷方面的疗效。测试了几种柱体方案，包括不同的放置方向、不同的放置位置、植入柱体的半径和阵列参数的不同设置以及柱体的不同杨氏模量。基于我们的模拟结果，纵向植入手术在一定程度上提高了软腭的刚度，并且横向植入被评估为改进现有手术方案的一个不错选择。此外，聚乙烯材料植入物的杨氏模量对软腭的加固效果有影响。
