Evaluation of micro-epidermal actuators on flexible substrate for noninvasive, pediatric-friendly conductive hearing aid

摘要 婴儿期和儿童期早期听力损失对语言和言语有不利影响 发展。听力损失必须尽早识别和纠正，以避免终身后果。 儿童听力障碍的一种主要类型是传导性，其中耳朵中的听觉通路是 阻塞或损坏，使声音不能正确地传导到内耳。暂时导通 听力损失(CHL)，包括中耳炎和鼓膜穿孔，可以通过药物或 小手术。耳道闭锁、管腔狭窄和听小骨畸形等解剖条件会导致 永久性CHL和更难解决的问题。普遍的做法是通过外科手术来矫正 耳道受损或将助听器植入头盖骨以绕过耳朵中的阻塞。然而，这些 手术是侵入性的，对新生儿和婴儿来说是一个挑战。由于风险，FDA的指导方针 防止5岁以下的儿童接受骨锚式助听器，这是成年人的标准设备。 这项研究的长期目标是找到新的策略，以非侵入性的方式将声音传递到内心 儿科患者的耳和地址慢性淋巴细胞白血病。中心假设是声音可以被转移到 内耳通过皮肤-骨骼路径，配以柔软的助听器。本项目的创新之处在于将芯片级， 柔性衬底上的超薄微机械换能器，以实现微表皮致动器(MEA)， 产生与皮肤直接接触的声音，震动骨骼并在真正无创的情况下绕过CHL 举止。我们提议的辅助将用超薄、低质量、灵活的电子设备产生120分贝SPL，这些电子设备具有 强韧地粘在婴儿的皮肤上，显示出了希望。这将消除所需的侵入性程序 用于矫正手术和听性骨整合植入物(AOI)以及风险和不适 与现有辅助器中的机械执行器和刚性部件相关联。 本申请的目的是评估柔性衬底对声耦合的效果， 软式助听器中的附着强度和运动相关噪声。为此，我们确定了以下三个主要目标 这个项目。在目标1中，将评估和表征表皮和MEAs之间的声学耦合。 假设柔性衬底将减少与皮肤的声学失配，并改善 进入耳朵的声音耦合。与面部和身体运动以及摩擦噪音相关的噪音有 目标2的特征。假设是柔软、共形、轻质的MEA将随着面部和 身体运动，减少整体噪音。皮肤和MEAs之间的粘合强度将在#年进行评估 目的3.由于体积小(1.5厘米×2.5厘米×300微米)，质量轻(120毫克)，弹性模数低， 底物与表皮温和粘合，粘合强度为1-2千帕。成功地实施了 这些目标将确定与儿童友好型传导性助听器相关的重要特征。

SUMMARY Hearing loss during infancy and early childhood has detrimental effects on language and speech development. Hearing loss must be identified and corrected as early as possible to avoid life-long consequences. One major type of pediatric hearing impairment is conductive, in which the auditory pathway in the ear is obstructed or damaged, preventing sounds from properly conducting to the inner ear. Temporary conductive hearing loss (CHL), including otitis media and tympanic membrane perforation, is addressed by medication or a minor surgery. Anatomical conditions such as aural atresia, canal stenosis and ossicular malformation result in permanent CHL and are more difficult to address. Prevalent practice calls for surgical procedures to correct the damage in the pathway or implant hearing aids into the skull to bypass the obstruction in the ear. However, these procedures are invasive and present challenges for newborns and infants. Because of the risks, FDA guidelines prevent children younger than 5 from receiving bone-anchored hearing aids that are standard devices for adults. The long-term goal of this research is to find new strategies to non-invasively transfer sounds into the inner ear and address CHL in pediatric patients. The central hypothesis is that the sounds can be transferred into the inner ear via the skin-bone route with soft hearing aids. The innovation in this project is to integrate chip-scale, ultrathin, micromechanical transducers on flexible substrates to achieve micro-epidermal actuators (MEAs), generating sounds in direct contact with the skin to vibrate the bone and bypass the CHL in a truly non-invasive manner. Our proposed aid will generate 120 dB SPL with ultrathin, low mass, flexible electronics, which have showed promise by robustly sticking to infants' skin. This will eliminate the need for invasive procedures required for corrective surgeries and auditory osseointegrated implants (AOI) as well as the risks and discomfort associated with mechanical actuators and rigid components in the existing aids. The objective of this application is to evaluate the efficacy of the flexible substrate on acoustic coupling, adhesion strength and motion-related noises in soft hearing aids. To that end, we defined three major aims for this project. In aim 1 the acoustic coupling between the epidermis and MEAs will be evaluated and characterized. The hypothesis is that the flexible substrate will reduce the acoustic mismatch with the skin and improve the acoustic coupling into the ear. The noises associated with facial and body motion as well as rubbing noises are characterized in aim 2. The hypothesis is that the soft, conformal, lightweight MEAs will move with facial and body motion, reducing overall noises. The adhesive strength between the skin and MEAs will be evaluated in aim 3. Because of the small size (1.5 cm × 2.5 cm × 300 µm), low mass (120 milligram), and low elastic modulus, the substrates gently bond to the epidermis with adhesion strength 1-2 kPa. The successful implementation of these aims will identify the important features tied to pediatric-friendly conductive hearing aids.