Lingual Mechanical Function During Swallowing

吞咽过程中的舌机械功能

• 批准号: 6618726
• 负责人: RICHARD J GILBERT
• 金额: $ 28.39万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-12 至 2006-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6618726
• 关键词: biomechanics; clinical research; dysphagia; electromyography; human subject; jaw movement; magnetic resonance imaging; mastication; mouth; muscle function; nuclear magnetic resonance spectroscopy; pharynxs; swallowing; tongue

DESCRIPTION (provided by applicant): The human tongue is an intricately configured muscular organ that plays a vital role during the physiological act of swallowing. During normal deglutition, the tongue first configures, then propels the ingested bolus from the oral cavity retrograde to the pharynx. From a clinical perspective, disorders of lingual function are exceedingly common in the elderly, in association with common neurological diseases, such as stroke, Parkinson's disease, and dementia, and are responsible for impaired nutrition and increased risk of aspiration pneumonia in these patient populations. Notwithstanding, there is minimal understanding of the way in which lingual muscular structure contributes to physiological function. The study of lingual mechanics has long been hampered by the complex myoarchitecture of the tissue and its material properties. As a result, mechanical function cannot be determined solely from global changes of shape, but necessitates the study of intramural dynamics. Our overall hypothesis is that the tongue functions as a muscular hydrostat, a unique structure in the human body, with the ability to both create motion and to provide the skeletal support for that motion. In order to test this hypothesis in the setting of human swallowing, we have considered the tongue from the perspective of a material continuum, and have thus depicted the tissue in terms of local fiber organization and strain. This project will study the quantitative relationship between three-dimensional myoarchitecture and regional mechanics during human swallowing. Our experimental approach uses non-invasive nuclear magnetic resonance imaging techniques to discern patterns of myoarchitecture and regional mechanics in vivo. In Specific Aim 1, the three-dimensional myoarchitecture of the tongue will be studied through the depiction of the local second order diffusion tensor derived from magnetic resonance imaging. In Specific Aim 2, the quantitative relationship between muscle fiber architecture and regional strain in association with swallowing will be determined by linkage of the structural measures with tagged magnetization. In Specific Aim 3, the regional mechanical adaptation to varying bolus volume and viscosity will be studied through combined diffusion tensor and tagged magnetization imaging under varying load conditions. This project should result in an improved understanding of structure-function relationships for the human tongue, and related human muscular hydrostats. It is anticipated that this understanding will result in novel hypotheses of pathological lingual function for patients with oropharyngeal dysphagia.

描述（由申请人提供）：人类的舌头是一个结构复杂的肌肉器官，在吞咽的生理行为中起着至关重要的作用。在正常吞咽过程中，舌头首先形成形状，然后将摄入的食团从口腔逆行至咽部。从临床角度来看，舌功能障碍在老年人中极为常见，与中风、帕金森病和痴呆等常见神经系统疾病有关，并导致这些患者群体的营养受损和吸入性肺炎的风险增加。尽管如此，人们对舌肌结构如何影响生理功能的方式了解甚少。舌力学的研究长期以来一直受到组织复杂的肌结构及其材料特性的阻碍。因此，机械功能不能仅根据形状的整体变化来确定，而是需要研究壁内动力学。我们的总体假设是，舌头起到肌肉静水器的作用，这是人体的独特结构，能够产生运动并为该运动提供骨骼支撑。为了在人类吞咽的环境中检验这一假设，我们从材料连续体的角度考虑了舌头，从而根据局部纤维组织和应变来描述组织。该项目将研究人体吞咽过程中三维肌肉结构与局部力学之间的定量关系。我们的实验方法使用非侵入性核磁共振成像技术来辨别体内肌肉结构和区域力学的模式。在具体目标 1 中，将通过描绘源自磁共振成像的局部二阶扩散张量来研究舌头的三维肌肉结构。在具体目标 2 中，肌纤维结构和与吞咽相关的区域应变之间的定量关系将通过结构测量与标记磁化的联系来确定。在具体目标 3 中，将通过组合扩散张量和不同负载条件下的标记磁化成像来研究对不同丸剂体积和粘度的区域机械适应。该项目应该能够更好地理解人类舌头的结构功能关系以及相关的人类肌肉静水状态。预计这种理解将导致口咽吞咽困难患者的病理性舌功能的新假设。