Rigato Cristina, Reinfeldt Sabine, Håkansson Bo, Fredén Jansson Karl-Johan, Renvall Erik, Eeg-Olofsson Måns
Division of Signal Processing and Biomedical Engineering, Department of Electrical Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.
Department of Otorhinolaryngology, Head and Neck Surgery, Sahlgrenska University Hospital, The Sahlgrenska Academy, University of Gothenburg, SE-413 46 Gothenburg, Sweden.
Hear Res. 2018 Apr;361:103-112. doi: 10.1016/j.heares.2018.01.007. Epub 2018 Jan 31.
Active transcutaneous bone conduction devices, where the transducer is implanted, are used for rehabilitation of hearing impaired patients by directly stimulating the skull bone. The transducer and the way it is attached to the bone play a central role in the design of such devices. The actual effect of varying the contact to bone has not been addressed yet. The aim of this study is therefore to compare how different attachment methods of the transducer to the bone for direct stimulation affect the ear canal sound pressure and vibration transmission to the ipsilateral cochlea. Three different attachments to the bone were tested: (A) via a flat small-sized surface, (B) via a flat wide surface and (C) via two separated screws. Measurements were done on four human heads on both sides. The attachments were compared in terms of induced cochlear promontory velocity, measured by a laser Doppler vibrometer, and ear canal sound pressure, measured by a low noise microphone. A swept sine stimulus was used in the frequency range 0.1-10 kHz. On an average level, the attachment method seems to affect the transmission mainly at frequencies above 5 kHz. Furthermore, the results suggest that a smaller contact surface might perform better in terms of transmission of vibrations at mid and high frequencies. However, when considering the whole frequency range, average results from the different attachment techniques are comparable.
有源经皮骨传导装置，其换能器是植入式的，通过直接刺激颅骨来用于听力受损患者的康复治疗。换能器及其与骨头的连接方式在这类装置的设计中起着核心作用。改变与骨头的接触方式的实际效果尚未得到研究。因此，本研究的目的是比较换能器与骨头的不同连接方式对直接刺激时耳道声压以及同侧耳蜗振动传递的影响。测试了三种不同的与骨头的连接方式：(A) 通过一个扁平的小尺寸表面，(B) 通过一个扁平的宽表面，以及(C) 通过两颗分开的螺钉。在四个人的双侧头部进行了测量。根据激光多普勒振动计测量的诱发耳蜗岬速度以及低噪声麦克风测量的耳道声压对这些连接方式进行了比较。在0.1 - 10千赫的频率范围内使用了扫频正弦刺激。平均而言，连接方式似乎主要在5千赫以上的频率影响传递。此外，结果表明较小的接触表面在中高频振动传递方面可能表现更好。然而，考虑整个频率范围时，不同连接技术的平均结果是可比的。
