Improving Restoration of Middle-Ear Function Following Blast Related Injuries

项目总结/摘要 军事人员的传导性听力损失通常是由爆炸相关的中耳损伤引起的， 可包括鼓膜破裂和中耳小骨脱位。目前的提案寻求 评估恢复听力的方法和设备，不仅适用于现役军人和退伍军人， 患有爆炸引起的传导性听力损失的人，也适用于其他经历传导性听力损失的人。 由于各种原因的听力损失（例如，鼓膜破裂、出生缺陷、中耳骨硬化）。而 这些损伤在临床上是可以治疗的，中耳病理学对听力的影响还没有很好的量化， 对于那些患有传导性听力的人来说，临床结果通常不能完全恢复正常听力 损失目前的建议旨在精确地测量复杂的振动模式沿沿着听骨 在中耳系统末端的链条和相关压力;附在鼓膜上的脐 膜和镫骨连接到耳蜗，在正常和特别是在各种病理 条件（损坏/修复/使用假体重建）。这些研究将使用激光多普勒 振动测量、独特的微压传感器和耳声发射（OAE）的直接测量。目标1将 评价系统性不同鼓膜穿孔对中耳音的影响 在动物模型中传播。鼓膜在声音传递中的作用将被探讨 在不同的穿孔情况下，自然地观察其对听小骨运动的影响 治愈的条件刺激后畸变产物耳声发射（DPOAE）的测量 将使用成对音调来量化对鼓膜的不同程度损伤的影响。 在目标2中，我们将测量具有模拟听骨链病变的动物模型中的声音传输。在 此外，异常听骨链对DPOAE的产生和声学特性的影响 将系统地探索，以开发诊断听力损失的定量工具， 设计和实施改进的治疗方法。目的3评估中耳声音 在临床修复的人耳的人尸体颞骨模型中的传输。使用直接压力 和速度测量，正常中耳结构和两个目前的功能差异， 采用修复中耳听骨链离断、砧骨/镫骨固定或 部分/全部听骨链置换使用假体，将被详细量化。拟议研究 将提供重要的信息，有助于提高我们的能力，具体诊断的原因， 传导性听力损失，指导改进治疗方法的发展，并协助合理 设计先进的假肢，更有效地恢复听力。

Project Summary/Abstract Conductive hearing loss in military personnel is commonly caused by blast-related middle ear injuries, which can include tympanic membrane rupture and dislocation of the middle-ear ossicles. The current proposal seeks to evaluate methods and devices for restoring hearing not only for active-duty military personnel and Veterans who suffer from a blast-induced conductive hearing loss, but also for others who experience conductive hearing loss for various reasons (e.g., ruptured eardrum, birth defects, stiffening of middle ear bones). While these injuries are clinically treatable, the effects of middle-ear pathology on hearing are not well quantified, and clinical outcomes often fail to completely restore normal hearing for those suffering from a conductive hearing loss. The current proposal seeks to precisely measure the complex vibrational patterns along the ossicular chain and related pressures at the ends of the middle ear system; the umbo attached to the tympanic membrane and stapes attached to the cochlea, under both normal and particularly under various pathological conditions (damaged/repaired/reconstructed using prosthesis). These studies will use Laser Doppler Vibrometry, unique micro-pressure sensors and direct measures of otoacoustic emissions (OAEs). Aim 1 will evaluate the effects of systematically varied tympanic membrane perforations on middle ear sound transmission in an animal model. The role of the tympanic membrane in sound transmission will be explored and its influence on the motion of the ossicles will be characterized under varied perforation and naturally healed conditions. Measurement of distortion product otoacoustic emissions (DPOAEs) following stimulation with paired tones will be used to quantify the effect of varying degrees of damage to the tympanic membrane. In Aim 2 we will measure sound transmission in an animal model with simulated ossicular chain pathologies. In addition, the effect of an abnormal ossicular chain on the production and acoustic characteristics of DPOAEs will be systematically explored in order to develop quantitative tools for diagnosing hearing loss and for use in the design and implementation of improved methods of treatment. Aim 3 evaluates middle ear sound transmission in human cadaver temporal bone models of clinically repaired human ears. Using direct pressure and velocity measurements, the functional differences between normal middle ear structures and two currently employed methods of repairing disarticulation of the middle ear ossicular chain, incus/stapes fixation or partial/total ossicular chain replacement using prostheses, will be quantified in detail. The proposed research will provide important information that will serve to improve our ability to specifically diagnose the causes of conductive hearing loss, direct the development of improved methods of treatment, and assist in the rational design of advanced prosthetics that more effectively restore hearing.