Quiet TMS: A Low-Acoustic-Noise Transcranial Magnetic Stimulation System

安静 TMS：低声学噪声经颅磁刺激系统

• 批准号: 9229084
• 负责人: Angel V Peterchev
• 金额: $ 35.1万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-26 至 2020-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9229084
• 关键词: Acoustic Stimulation; Acoustics; Address; Affect; Aging; Area; Arousal; Auditory; Auditory area; Basic Science; Biological Neural Networks; Brain; Brain Stem; Brain region; Characteristics; Child; Clinical Research; Data; Development; Devices; Earplug; Effectiveness; Elderly; Electroencephalography; Electromagnetic Energy; Electromagnetics; Electronics; FDA approved; Fetus; Frequencies; Functional Magnetic Resonance Imaging; Generations; Headache; Hearing; Human; Individual; Loudness; Magnetism; Measurement; Mechanics; Mediating; Mental Depression; Methods; Neurologic; Neurons; Neurosciences; Noise; Patients; Performance; Physiologic pulse; Positron-Emission Tomography; Prevention; Property; Protocols documentation; Risk; Safety; Shapes; Site; Structure; System; Techniques; Technology; Therapeutic; Tinnitus; Transcranial magnetic stimulation; Vulnerable Populations; base; clinical application; design; electric field; hearing impairment; human study; nervous system disorder; neural stimulation; neuroregulation; novel; prevent; prototype; relating to nervous system; repetitive transcranial magnetic stimulation; response; scale up; sound; tool; voltage

This project will develop a low-noise transcranial magnetic stimulation (TMS) system. TMS is a technique for non-invasive brain stimulation using strong, brief magnetic pulses. TMS is widely used as a tool for probing brain function and is an FDA approved treatment for depression. A significant limitation of TMS, however, is that the magnetic pulse delivery is associated with a loud clicking sound as high as 140 dB resulting from electromagnetic forces. The loud noise significantly impedes both basic research and clinical applications of TMS. First, it effectively makes TMS less focal since every click activates auditory cortex, brainstem, and other connected regions, synchronously with the magnetic pulse. Second, the repetitive clicking sound, both by itself or paired with synchronous activation at the TMS target site, can induce neuromodulation that can interfere with and confound the intended effects at the TMS target. Third, the clicking noise can compromise blinding of TMS studies and necessitates the use of sham conditions that replicate the sound but that could induce undesirable sound-mediated modulation effects as well. Finally, there are known safety concerns regarding hearing loss and induction of tinnitus, especially in vulnerable populations, as well as tolerability considerations, since TMS noise may contribute to headache and cause discomfort in some patients. Addressing this need, we propose a quiet TMS (qTMS) device that incorporates two key concepts: First, the dominant frequency of the TMS pulse sound (typically 2–5 kHz) will be shifted to higher frequencies that are above the human hearing upper threshold of about 20 kHz. This will be accomplished by making the magnetic pulse ultrabrief, and shaping it so that its fundamental frequency is above 20 kHz. Due to the strength–duration properties of the neural response, ultrabrief pulses require higher amplitude to achieve neural stimulation, but the total pulse energy is actually lower than for conventional pulses. Second, the TMS coil will be redesigned electrically and mechanically to generate suprathreshold electric field pulses while minimizing the sound emitted at audible frequencies (< 20 kHz). This will require the coil to sustain pulses with higher voltage and current but of briefer duration than conventional pulses, while minimizing the electromagnetic energy that is converted to and emitted as acoustic energy at frequencies below 20 kHz. The enhanced acoustic properties of the coil will be accomplished with a novel, layered coil design. We will design and build a qTMS device based on these concepts, aiming at an initial reduction of the acoustic noise of 40 dB compared to a conventional device. The neural and acoustic stimulation produced by qTMS will be characterized in bench-top measurements and a proof-of-concept human study. We present pilot data from a low-amplitude qTMS prototype already demonstrating reduction of noise by 19 dB with ultrabrief pulses, as well as data from a human study showing comparable neural activation with amplitude-adjusted brief versus long pulses. Thus, qTMS technology could enable more precise, effective, safe, and tolerable TMS.

该项目将开发低噪声trancranial磁刺激（TMS）系统。 TMS是一项技术 用于使用强，短磁脉冲的非侵入性脑刺激。 TMS被广泛用作探测工具 大脑功能，是FDA批准的抑郁症治疗方法。但是，TMS的一个重要局限性是 磁性脉冲传递与高达140 dB的响亮声音有关 电磁力。大声的噪音极大地阻碍了基础研究和临床应用 TMS。首先，由于每次点击都会激活听觉皮层，脑干和其他 连接区域，与磁脉冲同步。其次，重复的点击声本身 或与TMS目标位点的同步激活配对，可以诱导神经调节 与TMS目标处的预期效果并混淆。第三，点击噪声会损害盲目 TMS研究并有必要使用复制声音的假条件，但可能会引起声音 不良的声音介导的调制效果。最后，关于安全的问题 耳鸣的听力损失和诱导，尤其是在弱势群体中以及可容忍度 考虑因素，由于TMS噪声可能会导致标题并引起某些患者的不适。 在满足这种需求时，我们提出了一个安静的TMS（QTMS）设备，该设备结合了两个关键概念：首先， TMS脉冲声音的主要频率（通常为2-5 kHz）将转移到更高的频率 高于人类听力的上阈值约为20 kHz。这将通过使 磁性脉冲超信，并将其塑造，使其基本频率高于20 kHz。由于 神经响应的强度 - 呈呈呈呈粘合性，超纤维脉冲需要更高的放大器才能实现 神经刺激，但总脉冲能量实际上低于常规脉冲。第二，TMS 线圈将通过电气和机械重新设计，以产生上孔质电场脉冲，而 最大程度地减少在可听见的频率下发出的声音（<20 kHz）。这将要求线圈与 比常规脉冲更高的电压和电流，但布里夫持续时间更高，同时最小化 电磁能以低于20 kHz的频率转化为声能并发射为声能。这 线圈的增强声学特性将通过一种新型的分层线圈设计来实现。我们将设计 并基于这些概念构建QTMS设备，目的是初步降低40 dB的声学噪声 与常规设备相比。 QTM产生的神经和声学刺激将是 以台式测量和概念验证人类研究为特征。我们从一个 低振幅QTMS原型已经证明了用超纤维脉冲减少19 dB的噪声，AS 以及一项人类研究的数据，显示了与放大器调整后的简短相比的神经激活 长脉冲。那就是QTMS技术可以使更精确，有效，安全和可容忍的TMS。