Håkansson Bo, Jansson Karl-Johan Fredén, Tengstrand Tomas, Johannsen Leif, Eeg-Olofsson Måns, Rigato Cristina, Dahlström Elisabeth, Reinfeldt Sabine
Department of Electrical Engineering, Chalmers University of Technology, Gothenburg, Sweden,
Department of Audiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Med Devices (Auckl). 2018 Sep 6;11:301-312. doi: 10.2147/MDER.S171369. eCollection 2018.
A new prototype bone conduction (BC) transducer B250, with an emphasized low-frequency response, is evaluated in vestibular evoked myogenic potential (VEMP) investigations. The aim was to compare cervical (cVEMP) and ocular (oVEMP) responses using tone bursts at 250 and 500 Hz with BC stimulation using the B250 and the conventional B81 transducer and by using air conduction (AC) stimulation.
Three normal subjects were investigated in a pilot study. BC stimulation was applied to the mastoids in cVEMP, and both mastoid and forehead in oVEMP investigations.
BC stimulation was found to reach VEMP thresholds at considerably lower hearing levels than in AC stimulation (30-40 dB lower oVEMP threshold at 250 Hz). Three or more cVEMP and oVEMP responses at consecutive 5 dB increasing mastoid stimulation levels were only obtained in all subjects using the B250 transducer at 250 Hz. Similar BC thresholds were obtained for both ipsilateral and contralateral mastoid stimulation. Forehead stimulation, if needed, may require a more powerful vibration output.
Viable VEMP responses can be obtained at a considerably lower hearing level with BC stimulation than by AC stimulation. The cVEMP and oVEMP responses were similar when measured on one side and with the B250 attached to both ipsilateral and contralateral mastoids.
在一项前庭诱发肌源性电位（VEMP）研究中，对一种强调低频响应的新型骨传导（BC）换能器B250进行评估。目的是比较在250和500Hz使用短纯音，通过B250和传统B81换能器进行骨传导（BC）刺激以及通过气传导（AC）刺激时的颈肌（cVEMP）和眼肌（oVEMP）反应。
在一项初步研究中对三名正常受试者进行了调查。在cVEMP研究中，将骨传导刺激施加于乳突，在oVEMP研究中，将其施加于乳突和前额。
发现骨传导刺激达到VEMP阈值时的听力水平明显低于气传导刺激（在250Hz时，眼肌VEMP阈值低30 - 40dB）。仅在所有受试者使用250Hz的B250换能器时，在乳突刺激水平连续增加5dB的情况下获得了三个或更多的颈肌和眼肌VEMP反应。同侧和对侧乳突刺激获得的骨传导阈值相似。如有必要，前额刺激可能需要更强的振动输出。
与气传导刺激相比，骨传导刺激能在明显更低的听力水平下获得可行的VEMP反应。当在一侧测量且将B250连接到同侧和对侧乳突时，颈肌和眼肌VEMP反应相似。
