Yazama Hiroaki, Arii Shiro, Kataoka Hideyuki, Watanabe Tasuku, Kamitani Ryo, Fujiwara Kazunori
Department of Otolaryngology, Head and Neck Surgery, Faculty of Medicine, Tottori University, 36-1 Nishi-machi, Yonago 683-8504, Japan.
Kanki Rotordynamics Lab, 1646 Higashikanki-cyo, Kakogawa 675-0057, Japan.
Audiol Res. 2023 Jul 12;13(4):495-505. doi: 10.3390/audiolres13040044.
The cartilage-conduction pathway was recently proposed as a third auditory pathway; however, middle-ear vibrations have not yet been investigated in vivo. We aimed to measure the ossicles and bone vibration upon cartilage-conduction stimulation with a non-contact laser Doppler vibrometer. We recruited adult patients with normal ear structures who underwent cochlear implant surgery at our hospital between April 2020 and December 2022. For sound input, a cartilage-conduction transducer, custom-made by RION Corporation (Tokyo, Japan), was fixed to the surface of the tragus and connected to an audiometer to regulate the output. A posterior tympanotomy was performed and a laser beam was directed through the cavity to measure the vibration of the ossicles, cochlear promontory, and posterior wall of the external auditory canal. Five participants (three men, mean age: 56.4 years) were included. The mean hearing loss on the operative side was 96.3 dB HL in one patient, and that of the other patients was off-scale. The vibrations were measured at a sound input of 1 kHz and 60 dB. We observed vibrations of all three structures, demonstrating the existence of cartilage-conduction pathways in vivo. These results may help uncover the mechanisms of the cartilage-conduction pathway in the future.
软骨传导途径最近被提出作为第三条听觉通路；然而，中耳振动尚未在体内进行研究。我们旨在使用非接触式激光多普勒振动计测量软骨传导刺激时听小骨和骨骼的振动。我们招募了2020年4月至2022年12月期间在我院接受人工耳蜗植入手术且耳部结构正常的成年患者。对于声音输入，由日本东京的理音株式会社定制的软骨传导换能器固定在耳屏表面，并连接到听力计以调节输出。进行后鼓室切开术，将激光束穿过该腔以测量听小骨、蜗窗岬和外耳道后壁的振动。纳入了5名参与者（3名男性，平均年龄：56.4岁）。1例患者手术侧平均听力损失为96.3 dB HL，其他患者的听力损失超出范围。在1 kHz和60 dB的声音输入下测量振动。我们观察到所有三个结构的振动，证明了体内软骨传导途径的存在。这些结果可能有助于未来揭示软骨传导途径的机制。
