National Centre for Audiology, Faculty of Health Sciences, Western University, London, Ontario, Canada.
School of Communication Sciences and Disorders, Faculty of Health Sciences, Western University, London, Ontario, Canada.
Am J Audiol. 2024 Sep 3;33(3):695-704. doi: 10.1044/2024_AJA-23-00258. Epub 2024 May 13.
Bone conduction hearing devices (BCDs) that deliver sound across the skin (i.e., transcutaneous) are suitable for some individuals who have conductive or mixed hearing losses. Prescriptive targets for percutaneous devices are available, for example, from the Desired Sensation Level-Bone Conduction Hearing Device (DSL-BCD) algorithm. These targets, however, may require modification for use with transcutaneous BCDs. The current study investigated three key variables that may inform target modification: (a) comparison of thresholds measured using an audiometric bone conduction (BC) transducer versus transcutaneous BCDs that offer in situ threshold measurement, (b) transcutaneous BCD default force level outputs versus recommended DSL percutaneous BC targets, and (c) the preferred listening levels (PLLs) of adults wearing transcutaneous BCDs in a laboratory setting.
Bilateral conductive hearing loss was simulated in 20 normal-hearing adults via earplugs. Thresholds were measured using a B-71 BC transducer and two commercially available BCDs coupled to a soft headband. DSL percutaneous BC targets were generated, and PLLs were obtained for a 60-dB SPL speech stimulus. Force level outputs were measured using a skull simulator on the Audioscan Verifit2 at the hearing aids' default settings and at the participants' PLL for each device.
On average, audiometric BC thresholds were significantly better than those measured in situ with each BCD. PLLs were similar to prescribed targets for one device with the smoother response shape and agreed in the high frequencies for both devices.
In situ thresholds are significantly higher than audiometric BC thresholds, suggesting that device-based in situ measurement more accurately accounts for the signal transmission from transcutaneous BCDs. PLLs differed from the percutaneous targets and varied between devices, which may indicate that either target modifications or manipulations of device frequency response shaping are needed to approximate PLL with transcutaneous BCD devices.
通过皮肤（即经皮）传递声音的骨导听力设备（BCDs）适用于患有传导性或混合性听力损失的某些个体。例如，可从期望感觉水平-骨导听力设备（DSL-BCD）算法获得经皮设备的规定目标。然而，这些目标可能需要修改才能与经皮 BCD 一起使用。本研究调查了可能为目标修改提供信息的三个关键变量：（a）使用听力计骨导（BC）换能器测量的阈值与提供原位阈值测量的经皮 BCD 之间的比较，（b）经皮 BCD 默认力水平输出与推荐的 DSL 经皮 BC 目标之间的比较，以及（c）在实验室环境中佩戴经皮 BCD 的成年人的首选聆听水平（PLLs）。
通过耳塞模拟 20 名正常听力成年人的双侧传导性听力损失。使用 B-71 BC 换能器和两个商业上可获得的耦合到软头带的 BCD 测量阈值。生成 DSL 经皮 BC 目标，并为 60dB SPL 语音刺激获得 PLL。使用颅骨模拟器在 Audioscan Verifit2 上在助听器的默认设置和每个设备的参与者 PLL 处测量力水平输出。
平均而言，听力计 BC 阈值明显优于每个 BCD 的原位测量值。PLL 与一种设备的规定目标相似，该设备的响应形状更平滑，两种设备在高频处均一致。
原位阈值明显高于听力计 BC 阈值，这表明基于设备的原位测量更准确地考虑了经皮 BCD 信号传输。PLL 与经皮目标不同，并且在设备之间有所不同，这可能表明需要对目标进行修改或对设备频率响应整形进行操作，以使用经皮 BCD 设备近似 PLL。
