Oropharyngeal Bolus Flow Dynamics

描述(申请人提供)：在美国，目前超过60岁的4400万人中，估计有15%-30%的人患有吞咽困难(吞咽障碍的通称)，还有大约50%的疗养院患者。除了吞咽障碍对个人生活质量有深远影响外，这些障碍还构成重大的健康风险。例如，考虑吸入现象，吸入的物质进入气管和肺，而不是食道和胃肠道。这种行为可能会将口腔细菌传播到肺部，是吸入性肺炎的危险因素，对于住院和住院的老年人口来说，吸入性肺炎是一种严重的、往往危及生命的健康问题。在正常的吞咽过程中，舌头与上颚的连续接触会将吞咽的物质推出口腔并通过咽部。咽部肌肉的收缩然后将这种物质移动到食道。然而，对这些推进力的反应取决于推进剂的物理性质，如粘度和密度。PI的研究计划的长期目标是将现代计算建模策略应用到口咽吞咽的研究中。鉴于吞咽过程在很大程度上是机械性的，这种计算工具的开发和应用有可能增强我们对口咽吞咽机制以及治疗和诊断工具的理解。考虑到模拟这一过程的复杂性，我们提出了一个保守的研究计划，重点是开发口咽吞咽的二维计算机模拟。考虑到燕子的这一部分可以描述为气液混合物通过具有时间相关边界的复杂几何形状的高度瞬变流动，我们的目标是开发一个能够模拟任意类流体材料的自适应有限元模型。如果成功，进一步的工作将把该模式扩展到三维。 公共卫生相关性：在美国，目前超过60岁的4400万人中，估计有15%-30%的人患有吞咽困难(吞咽障碍的通称)，还有大约50%的疗养院患者。虽然计算机建模已广泛应用于心血管、神经系统等其他生理系统，但目前用于吞咽的模型还很少。当前的提议解决了这样一种基于计算机的建模工具的开发，该工具用于预测液体丸在穿过口咽腔时的运动。我们对这个项目的长期愿景是双重的。首先，我们设想了一种分析工具，以帮助临床医生和科学家了解口咽吞咽的基本机制。这将自然而然地导致一种优化工具，它可以添加到目前的工具库中，用于分析现有的诊断和治疗程序并开发新的程序。

DESCRIPTION (provided by applicant): In the United States, 15-30 % of the 44 million individuals currently over the age of 60 are estimated to have dysphagia (a general term for swallowing disorders), along with an estimated 50 % of nursing home patients. In addition to the profound effect that swallowing disorders have on an individual's quality of life, these disorders also pose significant health risks. For example, consider the phenomena of aspiration, in which ingested material enters the trachea and lungs rather than the esophagus and gastrointestinal tract. This behavior may transport oral bacteria to the lungs and is a risk factor for aspiration pneumonia, a serious and often life-threatening health concern for the institutionalized and hospitalized geriatric population. During the normal swallow, the sequential contact of the tongue against the palate propels swallowed material out of the oral cavity and through the pharynx. Contraction of the pharyngeal musculature then moves this material into the esophagus. Flow in response to these propulsive forces, however, depends on the physical properties of the bolus, such as viscosity and density. The long-term goal of the PI's research program is to apply modern computational modeling strategies to the study of oropharyngeal swallowing. Given the largely mechanical nature of the swallowing process, the development and application of such computational tools has the potential to enhance our understanding of both oropharyngeal swallowing mechanics as well as therapeutic and diagnostic tools. Given the complexities associated with simulating this process, we are proposing a conservative research plan, which focuses on the development of a two-dimensional computer simulation of oropharyngeal swallowing. Given that this portion of the swallow may be described as the highly transient flow of an air-liquid mixture through a complex geometry with time-dependent boundaries, we aim to develop an adaptive finite element model that is able to simulate arbitrary fluid-like materials,. If successful, further work will extend the mode to three dimensions. Public Health Relevance: In the United States, 15-30 % of the 44 million individuals currently over the age of 60 are estimated to have dysphagia (a general term for swallowing disorders), along with an estimated 50 % of nursing home patients. Although computer modeling has been extensively applied to other physiological system, such as cardiovascular and neurologic, very few models have been developed for swallowing. The current proposal addresses the development of such a computer based modeling tool to predict the motions of a fluid bolus as it traverses the oropharyngeal cavity. Our long-term vision for this program is two-fold. First, we envision an analysis tool to aid clinicians and scientists working on bolus transport in understanding the basic mechanics of oropharyngeal swallowing. This will lead naturally to an optimization tool, which could be added to the current arsenal of tools with which to analyze available diagnostic and therapeutic procedures and to develop new ones.