Eardrum function in live and cadaveric ears: Research and clinical relevance

摘要： 中耳疾病引起的慢性传导性听力损失可导致耳蜗神经病变。虽然我们的 中耳疾病的诊断和管理并不完美，部分原因是对中耳疾病的知识不完整。 鼓膜的声音传输功能。关于鼓膜功能的多种相互矛盾的理论已经被 在过去的150年里，这些理论都是基于不完整的描述和误解， 现有的鼓膜特征。几乎所有以前的鼓膜对声音反应的测量都有 使用稳态音调刺激，而环境声音，如音乐，噪音和语音，是瞬态的 在自然界中。真实的世界中的鼓膜瞬态响应知之甚少。不完全了解 鼓膜也限制了我们对如何修复患病耳朵的看法。我们在这项研究中的第一个目标是提供 这是区分这些不同的鼓膜功能理论的证据。我们的第二个目标是提高 我们对鼓膜对瞬时声音反应的了解。我们的第三个目标是探索 鼓膜瞬态反应测定在中耳疾病鉴别诊断中的应用。到 为了实现这些目标，我们提出了本研究的三个目标。Aim 1采用最先进的高速 本实验室研制的全息干涉测量系统（HSHIS）用于定量鼓膜瞬态 在非常高的空间（> 100，000点）和时间上对声学和机械瞬态刺激的反应 （>每秒100 k帧）分辨率。“实验模态分析”将被应用于提取三个重要的 然而，鼓膜的量化特征很差：（1）自然频率;（2）幅度和空间 模态响应模式;（3）阻尼。目的1的结果将使我们能够了解和描述鼓膜 功能的复杂程度，还没有提供，并解决矛盾的理论耳膜 功能目的2将用模拟中耳的尸体人耳来量化鼓膜瞬态响应 疾病目的2中的结果将评估病理耳的鼓膜功能，并评估我们的 技术作为鉴别诊断中耳疾病的客观工具。目标3将研究耳膜 在正常和患病的中耳条件下，如渗出性中耳炎，在活的灰鼠耳中发挥作用。 很少有详细的表面运动的活鼓膜已在文献中报道，结果在目标3将填补 在这个间隙。在安乐死后立即重复测量，以直接量化任何死后变化 鼓膜功能。这一目标也作为一个试点研究，以评估我们的系统的临床效用之前， 在病人身上进行临床试验。

ABSTRACT: Chronic conductive hearing loss due to middle-ear diseases can lead to cochlear neuropathy. While our diagnosis and management of middle-ear diseases are not perfect, in part due to incomplete knowledge of the eardrum function for sound transmission. Multiple contradictory theories of eardrum function have been proposed in the past 150 years. These theories are based on incomplete descriptions and misinterpretation of existing eardrum characterizations. Almost all previous measurements of the eardrum response to sound have used steady-state tonal stimuli, while environmental sounds, such as music, noises and speech, are transient in nature. Little is known about the eardrum transient response in the real world. Incomplete knowledge of the eardrum also limits our views on how to repair the diseased ear. Our first goal in this study is to provide evidence to distinguish between these different theories of the eardrum function. Our second goal is to improve our knowledge of the eardrum response to transient sound. Our third goal is to explore clinical application of the measurement of the eardrum transient response for differential diagnosis of middle-ear diseases. To achieve these goals, we propose three aims in this study. Aim 1 employs a state-of-the-art High Speed Holographic Interferometry System (HSHIS) developed in our laboratory to quantify the eardrum transient responses to acoustic and mechanical transient stimuli, at a very high spatial (>100,000 points) and temporal (>100k frames per second) resolution. ‘Experimental modal analysis’ will be applied to extract three important yet poorly quantified characteristics of the eardrum: (1) natural frequencies; (2) the magnitude and spatial pattern of modal responses; (3) damping. Results in aim 1 will enable us to understand and describe eardrum function with a level of sophistication that has not been available, and resolve contradictory theories of eardrum function. Aim 2 will quantify the eardrum transient response in cadaveric human ears with simulated middle-ear diseases. Results in aim 2 will evaluate eardrum function in pathological ears, and assess the use of our techniques as an objective tool for differential diagnosis of middle-ear diseases. Aim 3 will study the eardrum function in live chinchilla ears in normal and diseased middle ear conditions, such as Otitis Media with Effusion. Very little detailed surface motion of the live eardrum has been reported in the literature, results in aim 3 will fill in that gap. Measurements will be repeated just after euthanasia to directly quantify any post-mortem changes in eardrum function. This aim also serves as a pilot study to evaluate the clinical utility of our system before clinical trials in patients.