Department of Psychiatry & Behavioral Sciences, Duke University, Durham, NC, 27710, USA.
Department of Psychiatry & Behavioral Sciences, Duke University, Durham, NC, 27710, USA; Department of Electrical & Computer Engineering, Duke University, Durham, NC, 27708, USA; Department of Neurosurgery, Duke University, Durham, NC, 27710, USA.
Brain Stimul. 2020 May-Jun;13(3):873-880. doi: 10.1016/j.brs.2020.03.004. Epub 2020 Mar 12.
Accurate data on the sound emitted by transcranial magnetic stimulation (TMS) coils is lacking.
We recorded the sound waveforms of seven coils with high bandwidth. We estimated the neural stimulation strength by measuring the induced electric field and applying a strength-duration model to account for different waveforms.
Across coils, at maximum stimulator output and 25 cm distance, the sound pressure level (SPL) was 98-125 dB(Z) per pulse and 76-98 dB(A) for a 20 Hz pulse train. At 5 cm distance, these values were estimated to increase to 112-139 dB(Z) and 90-112 dB(A), respectively.
The coils' airborne sound can exceed some exposure limits for TMS subjects and, in some cases, for operators. These findings are consistent with the current TMS safety guidelines that recommend the use of hearing protection.
经颅磁刺激（TMS）线圈发出声音的准确数据尚不清楚。
我们用高带宽记录了七个线圈的声音波形。我们通过测量感应电场并应用强度-时间模型来估计神经刺激强度，以考虑不同的波形。
在最大刺激器输出和 25 厘米距离处，每个脉冲的声压级（SPL）为 98-125dB（Z），20Hz 脉冲串为 76-98dB（A）。在 5 厘米的距离处，这些值估计会增加到 112-139dB（Z）和 90-112dB（A）。
线圈的空气传播声音可能超过 TMS 受试者和某些情况下操作人员的某些暴露限值。这些发现与当前 TMS 安全指南一致，该指南建议使用听力保护。
