Inouye Joshua M, Pelland Catherine M, Lin Kant Y, Borowitz Kathleen C, Blemker Silvia S
*Departments of Biomedical Engineering †Mechanical and Aerospace Engineering, University of Virginia ‡Departments of Plastic Surgery §Therapy Service, Speech-Language Pathology, University of Virginia Health System ||Department of Orthopaedic Surgery, University of Virginia, Charlottesville, VA.
J Craniofac Surg. 2015 May;26(3):658-62. doi: 10.1097/SCS.0000000000001441.
The levator veli palatini (LVP) muscle has long been recognized as the muscle that contributes most to velopharyngeal (VP) closure and is therefore of principal importance for restoring normal speech in patients with a cleft palate. Different surgical reconstructive procedures can utilize varying degrees of LVP overlap, and this study developed a new finite-element model of VP closure designed to understand the biomechanical effects of LVP overlap. A three-dimensional finite-element model was created from adult anatomical dimensions and parameters taken from the literature. Velopharyngeal function was simulated and compared with experimental measurements of VP closure force from a previous study. Varying degrees of overlap and separation of the LVP were simulated, and the corresponding closure force was calculated. The computational model compares favorably with the experimental measurements of closure force from the literature. Furthermore, the model predicts that there is an optimal level of overlap that maximizes the potential for the LVP to generate closure force. The model predicts that achieving optimal overlap can increase closure force up to roughly 100% when compared with too little or too much overlap. The results of using this new model of VP closure suggest that optimizing LVP overlap may produce improved surgical outcomes due to the intrinsic properties of muscle. Future work will compare these model predictions with clinical observations and provide further insights into optimal cleft palate repair and other craniofacial surgeries.
腭帆提肌（LVP）长期以来一直被认为是对腭咽（VP）闭合贡献最大的肌肉，因此对于腭裂患者恢复正常语音至关重要。不同的手术重建程序可以利用不同程度的LVP重叠，本研究开发了一种新的VP闭合有限元模型，旨在了解LVP重叠的生物力学效应。根据成人解剖尺寸和文献中的参数创建了三维有限元模型。模拟了腭咽功能，并与先前研究中VP闭合力的实验测量结果进行了比较。模拟了LVP不同程度的重叠和分离，并计算了相应的闭合力。该计算模型与文献中闭合力的实验测量结果相比具有优势。此外，该模型预测存在一个最佳重叠水平，可使LVP产生闭合力的潜力最大化。该模型预测，与重叠过少或过多相比，实现最佳重叠可使闭合力增加约100%。使用这种新的VP闭合模型的结果表明，由于肌肉的固有特性，优化LVP重叠可能会改善手术效果。未来的工作将把这些模型预测与临床观察结果进行比较，并为最佳腭裂修复和其他颅面手术提供进一步的见解。
