Mechanisms of Conductive Presbycusis in Humans

人类传导性老年性耳聋的发病机制 与年龄相关的高频听力损失(老年性耳聋)几乎是一种普遍经历的疾病，影响 仅在美国就有数千万人，每年在全球造成超过7500亿美元的损失。 老年性耳聋导致理解语言困难，听不到环境声音，如果 如果不加以解决，可能会导致社会孤立。考虑到目前的人口趋势， 老年性耳聋预计会加速。尽管老年性耳聋很普遍，但关于老年性耳聋仍有许多未知之处。 其发病机制。长期以来，老年性耳聋一直被认为是感觉神经功能障碍的继发性疾病， 但新出现的证据表明，传导性病理与老年性耳聋有关。 临床评估听力的主要方法是行为纯音(500-8 kHz)测听。 扩展的高频空气传导测试(&gt；8 kHz)现在通常进行，因为有了新的知识 高频声音对语音理解和声音定位的作用。不幸的是，临床骨 传导测试在4 kHz停止。在4 khz以上，标准刺激换能器的限制主要是 与20世纪50年代持平，缺乏标准化的骨传导标准限制了高频研究 传导损耗。感觉神经性和传导性老年性耳聋之间的区别不是常规的操作， 但这很有趣，因为：1)先前的研究表明，中耳内的离散变化可以导致 隔离的高频传导损耗(即：具有正常的低频阈值)和2)我们的能力 通过手术修复中耳。年龄的患病率和功能意义的进一步调查- 相关的中耳改变是必要的，以确保老年性耳聋的新疗法是适当的 导演。 新开发的无高频限制的骨传导换能器允许综合骨骼 频率高达16 kHz的传导测试。新型换能器将有助于最终确定 临床上存在传导性或混合性老年性耳聋，揭示了衰老对功能的影响。 中耳。发展可靠的高频传导性听力损失测试具有重要意义 除了老年性耳聋，还包括中耳手术后的听力评估。我们的目标是找出 传导性老年性耳聋的发病机制及高频可靠诊断方法的建立 传导性听力损失。我们假设老年性耳聋患者的一个子集已经增加了听骨。 顺应性导致传导性或混合性高频听力损失。

Mechanisms of Conductive Presbycusis In Humans Age-related high frequency hearing loss (presbycusis) is a near universally experienced condition, affecting tens of millions of individuals in the United States alone and costing worldwide more than $750 billion per year. Presbycusis results in difficulty understanding speech, problems hearing environmental sounds and, if unaddressed, can lead to social isolation. Given current demographic trends, the societal burden of presbycusis is expected to accelerate. Despite the prevalence of presbycusis, much remains unknown about its etiologic mechanisms. Presbycusis has long been assumed to be secondary to sensorineural dysfunction, but emerging evidence suggests conductive pathology contributes to presbycusis. The principal method for clinical evaluation of hearing is behavioral pure tone (500-8kHz) audiometry. Extended high frequency air conduction testing (>8kHz) is now commonly performed given new knowledge on the role of high frequency sound for speech understanding and sound localization. Unfortunately, clinical bone conduction testing stops at 4kHz. Above 4kHz, limitations in standard stimulus transducers that are largely unchanged from the 1950s, and a lack of normative bone conduction standards limit study of high frequency conductive loss. Differentiation between sensorineural and conductive presbycusis is not routinely performed, but is of interest because: 1) prior work demonstrates discrete changes within the middle ear can lead to isolated high frequency conductive loss (ie: with normal low-frequency thresholds) and 2) our ability to surgically repair the middle ear. Further investigation into the prevalence and functional significance of age- related middle ear change is necessary to ensure emerging therapies for presbycusis are appropriately directed. Newly developed bone conduction transducers without high frequency limitations permit comprehensive bone conduction testing at frequencies up to 16kHz. Novel transducers will help to finally establish whether a clinically relevant conductive or mixed presbycusis exists, shedding light on the functional effects of the aging middle ear. Development of reliable testing for high frequency conductive hearing loss carries implications beyond presbycusis, including post-middle-ear-surgery hearing assessment. Our goal is to identify mechanisms of conductive presbycusis and to establish methods to reliably diagnose high frequency conductive hearing loss. We hypothesize that a subset of patients with presbycusis have increased ossicular compliance resulting in conductive or mixed high frequency hearing loss.