The Relationship Between Vortices, Acoustics, and Vibration in Vocal Fold Asymmetries

项目摘要。 单侧声带麻痹（UVFP）的常见手术，如1型甲状腺成形术， 通过关闭正常和正常之间的膜间隙来提高发声效率（VE） 麻痹性褶皱VE测量声门下空气动力学功率被转化为 声功率然而，即使在手术治疗后，一些患者报告症状， 如声音疲劳、投射能力下降以及在嘈杂环境中清晰度下降。 这些不稳定的症状将与相对于正常声音的VE减少有关， 提示增加VE可进一步改善这些症状。我们以前的工作在 切除的犬喉表明，这种进一步的改善是可能的， 修改程序。例如，我们发现了一个令人惊讶的结果， 皱襞下方组织（声门下区）的VE高于皱襞内侧 尽管两种手术都关闭了内侧-外侧膜间隙， 此外，纳入杓状软骨内收增加了VE相对于声门下内侧 一个人然而，要将这些在动物身上的手术发现转化为患者，需要更深入的研究。 了解各种治疗方法的改变如何以及为什么会影响VE。在先前的工作中， 发现在闭合过程中褶皱之间会发生旋转运动（涡流）。这些涡流 产生负压，使褶皱更快地闭合， 声强和VE。我们知道褶皱的底部比上部更硬 部分;这被称为垂直刚度梯度（VSG）。我们还发现， VSG产生较弱的涡流和减少的VE。在第一个目标中，我们将进一步研究 VSG对VE的影响。在第二个和第三个目标中，我们将研究如何以及为什么不同 UVFP的处理影响VE。该应用为临床应用VE奠定了基础， 用于优化UVFP的临床治疗。

Project summary. Common operations for unilateral vocal fold paralysis (UVFP), such as Thyroplasty Type 1, improve vocal efficiency (VE) by closing the membranous gap between the normal and paralyzed fold. VE measures the degree to which subglottal aerodynamic power is translated to acoustic power. However, even after surgical treatment, some patients report symptoms such as vocal fatigue, decreased projection, and decreased intelligibility in noisy environments. These recalcitrant symptoms will be associated with reduced VE relative to normal voice, suggesting that enhancing VE could further ameliorate these symptoms. Our previous work in the excised canine larynx suggests that this further improvement is possible by certain modifications to the procedure. For example, we found the surprising result that medialization of the tissue below the fold (infraglottal region) results in higher VE than medialization of the fold itself (glottal) even though both operations close the medial-lateral membranous gap. Additionally, inclusion of arytenoid adduction increased VE relative to infraglottal medialization alone. However, to translate these surgical findings in animals to patients requires a deeper understanding about how and why various treatment modifications affect VE. In prior work we found that rotational motion (vortices) occur between the folds during closing. These vortices produce negative pressures that cause the folds to close together faster, which increase acoustic intensity and VE. We know that the bottom part of the folds is stiffer than the upper part; this is referred to as the vertical stiffness gradient (VSG). We have also found that lower VSG produces weaker vortices and decreased VE. In the first aim, we will further examine the effect of the VSG on VE. In the second and third aim, we will look at how and why different treatments for UVFP affect VE. This application lays the foundation for using VE clinically, and for optimizing clinical treatments for UVFP.