The Relationship between Vortices, Acoustics, and Vibration in Vocal Fold Assymet

描述（由申请人提供）：许多嗓音障碍的特征在于结构性声带不对称，例如声带左右位置、高度、长度或硬度的差异（例如单侧声带麻痹和瘫痪、声带息肉、声带瘢痕等）。当不对称较轻时，目前的疗法对大多数患者有效。然而，当不对称性显著或多重时，结果就更不确定。这些患者代表了一个重要的健康问题，因为他们的声音障碍的严重程度显着影响他们的身体，心理和经济。在任何领域，关于干预策略的临床决策都取决于临床结果数据和对潜在机制的理解。对于这些患者，由于临床数据有限，而且问题如此复杂，因此科学地了解结构不对称如何影响声带振动和声音产生尤为重要。 人们早就认识到喉部气流中存在涡流或旋转运动区域，但其相关性尚不清楚。使用完善的实验和理论方法，从工程，我们已经发现的证据表明，涡结构是特别相关的情况下，声带不对称。在这项先前的工作中，由K-8资助的主要研究者，我们的团队已经测量了发音气流在切除犬喉的速度场，特别是在量化涡流的兴趣。我们完成的研究（Khosla等人，2007，2008 a和2009; Murugappan，Khosla等人，2009）为本申请的总体假设提供了支持性基础，该总体假设是：声门气流包含对声学有显著贡献的某些涡旋结构;并且在某些喉部病变中，这些涡旋结构被减少或消除。正是这些涡流的改变和/或抑制导致了异常的发声。最有效地恢复特定漩涡的治疗将具有最好的语音效果。 为了检验中心假设，我们建议围绕以下具体目标组织我们的研究。将使用切除的犬和人喉用于所有目的。 具体目标1 -使用计算和验证的切除半喉模型，表征涡流和组织弹性对声带振动和声学的影响。具体目标2 -涡流、组织弹性、声带振动和声学将作为不同的临床相关结构不对称的函数进行测量。具体目标3 -在单侧声带麻痹的单一手术或以下手术组合后，测量结构不对称、振动不对称和声学的变化：1型甲状腺成形术、内收性软骨固定术和环甲状软骨半脱位。 公共卫生相关性：拟议研究的结果将为声带不对称患者的临床研究提供一种方法。展望未来，在此分辨率下的发声研究将与喉成像中的先进技术（例如视频记录（Svec等人）和高速摄像（Delyiski））很好地协同作用，因为可用的临床技术允许更精确和可靠地识别不对称。这些发现将对喉部产生深远的影响，因为这些结果可能适用于导致声带不对称的喉部其他情况，如声带瘢痕和声带沟。这些结果将产生积极的影响，因为新的知识将导致改进的诊断和临床技术，否则无法发展。

DESCRIPTION (provided by applicant): Many voice disorders feature structural vocal fold asymmetries, such as a difference in vocal fold left-right position, height, length or stiffness (e.g. unilateral vocal fold paresis and paralysis, vocal fold polyps, vocal fold scarring, etc.). When the asymmetries are mild, present therapies are effective for most patients. However, when the asymmetries are significant or multiple, outcomes are more uncertain. Such patients represent an important health problem, because the severity of their voice disorder significantly affects them physically, psychologically and economically. In any field, clinical decision-making about intervention strategies depends on a combination of clinical outcome data and the understanding of underlying mechanisms. For these patients, both because clinical data are limited and because the problems are so complex, scientific understanding of how structural asymmetries affect vocal fold vibration and voice production is particularly important. It has long been acknowledged that vortices, or areas of rotational motion, occur in the laryngeal airflow, but their relevance has not been clear. Using well-established experimental and theoretical approaches from engineering, we have found evidence that vortical structures are particularly relevant in cases of vocal fold asymmetries. In this previous work, supported by a K-8 grant to the principal investigator, our team has measured velocity fields of phonatory airflow in excised canine larynges, with particular interest in quantifying vortices. Our completed studies (Khosla et al., 2007, 2008a and 2009; Murugappan, Khosla et al., 2009) provide a supportive foundation to the overarching hypothesis of this application, which is: glottal airflow contains certain vortical structures that significantly contribute to the acoustics; and that in certain laryngeal pathologies, these vortical structures are reduced or eliminated. It is the modification and/or suppression of these vortices that contribute to abnormal voice production. Treatments that most effectively restore specific vortices will have the best voice outcomes. In order to test the central hypothesis, we propose to organize our study around the following specific aims. Excised canine and human larynges will be used for all aims. Specific Aim 1 - Using computational and validated excised hemilarynx models, characterize the effects of vortices and tissue elasticity on vocal fold vibration and acoustics. Specific Aim 2 - Vortices, tissue elasticity, vocal fold vibration and acoustics will be measured as functions of different, clinically relevant structural asymmetries. Specific Aim 3 -The change in structural asymmetries, vibratory asymmetries and acoustics will be measured after a single procedure or a combination of the following procedures for unilateral vocal fold paralysis: Thyroplasty Type 1, Adduction Arytenopexy and Cricothyroid Subluxation. PUBLIC HEALTH RELEVANCE: The results of the proposed research will provide an approach to clinically study patients with vocal fold asymmetry. Looking forward, the study of phonation at this resolution will synergize well with advancing technologies in laryngeal imaging, such as videokymography (Svec et al) and high speed videography (Delyiski) as available clinical technology allows for more precise and reliable identification of asymmetries. The findings will have far reaching impact in laryngology as the results may be applicable to other conditions in the larynx that result in vocal fold asymmetries , such as vocal fold scarring and vocal fold sulcus. These results will have positive impact, since the new knowledge will result in improved diagnostic and clinical techniques that could not be otherwise developed.