Objective: Currently available treatments for kinetic tremor can cause intolerable side effects or be highly invasive and expensive. Even though several studies have shown the positive effects of external feedback (i.e., electrical stimulation) for suppressing tremor, such approaches have not been fully integrated into wearable real-time feedback systems. Method: We have developed a wireless wearable stimulation system that analyzes upper limb tremor using a three-axis accelerometer and that modulates/attenuates tremor using peripheral-nerve electrical stimulation with adjustable stimulation parameters and a real-time tremor detection algorithm. We outfitted nine subjects with tremor with a wearable system and a set of surface electrodes placed on the skin overlying the radial nerve and tested the effects of stimulation with nine combinations of parameters for open- and closed-loop stimulation on tremor. To quantify the effects of the stimulation, we measured tremor movements, and analyzed the dominant tremor frequency and tremor power. Results:Baseline tremor power gradually decreased over the course of 18 stimulation trials. During the last trial, compared with the control trial, the reduction rate of tremor power was 42.17 ± 3.09%. The dominant tremor frequency could be modulated more efficiently by phase-locked closed-loop stimulation. The tremor power was equally reduced by open- and closed-loop stimulation. Conclusion: Peripheral nerve stimulation significantly affects tremor, and stimulation parameters need to be optimized to modulate tremor metrics. Clinical Impact: This preliminary study lays the foundation for future studies that will evaluate the efficacy of the proposed closed-loop peripheral nerve stimulation method in a larger group of patients with kinetic tremor.

中文翻译：

---

基于周围神经刺激来减弱特发性震颤的可穿戴系统


目的：目前可用的运动性震颤治疗方法可能会导致无法忍受的副作用，或者具有高度侵入性且昂贵。尽管一些研究已经表明外部反馈（即电刺激）对于抑制震颤具有积极作用，但此类方法尚未完全集成到可穿戴实时反馈系统中。方法：我们开发了一种无线可穿戴刺激系统，该系统使用三轴加速度计分析上肢震颤，并使用具有可调刺激参数和实时震颤检测算法的周围神经电刺激来调节/减弱震颤。我们为九名患有震颤的受试者配备了可穿戴系统和一组放置在桡神经上方皮肤上的表面电极，并测试了开环和闭环刺激的九种参数组合对震颤的刺激效果。为了量化刺激的效果，我们测量了震颤运动，并分析了主要震颤频率和震颤功率。结果：在 18 次刺激试验过程中，基线震颤强度逐渐下降。在上次试验中，与对照试验相比，震颤功率降低率为42.17±3.09%。通过锁相闭环刺激可以更有效地调节主导震颤频率。开环和闭环刺激均等地降低了震颤强度。结论：周围神经刺激显着影响震颤，需要优化刺激参数来调节震颤指标。 临床影响：这项初步研究为未来的研究奠定了基础，这些研究将评估所提出的闭环周围神经刺激方法在更大范围的运动性震颤患者中的疗效。