Debarros Jean, Gaignon Lea, He Shenghong, Pogosyan Alek, Benjaber Moaad, Denison Timothy, Brown Peter, Tan Huiling
Annu Int Conf IEEE Eng Med Biol Soc. 2020 Jul;2020:3367-3370. doi: 10.1109/EMBC44109.2020.9176665.
Continuous high frequency Deep Brain Stimulation (DBS) is a standard therapy for several neurological disorders. Closed-loop DBS is expected to further improve treatment by providing adaptive, on-demand therapy. Local field potentials (LFPs) recorded from the stimulation electrodes are the most often used feedback signal in closed-loop DBS. However, closed-loop DBS based on LFPs requires simultaneous recording and stimulating, which remains a challenge due to persistent stimulation artefacts that distort underlying LFP biomarkers. Here we first investigate the nature of the stimulation-induced artefacts and review several techniques that have been proposed to deal with them. Then we propose a new method to synchronize the sampling clock with the stimulation pulse so that the stimulation artefacts are never sampled, while at the same time the Nyquist-Shannon theorem is satisfied for uninterrupted LFP recording. Test results show that this method achieves true uninterrupted artefact-free LFP recording over a wide frequency band and for a wide range of stimulation frequencies.Clinical relevance-The method proposed here provides continuous and artefact-free recording of LFPs close to the stimulation target, and thereby facilitates the implementation of more advanced closed-loop DBS using LFPs as feedback.
连续高频深部脑刺激（DBS）是多种神经疾病的标准疗法。闭环DBS有望通过提供适应性按需治疗进一步改善治疗效果。从刺激电极记录的局部场电位（LFP）是闭环DBS中最常用的反馈信号。然而，基于LFP的闭环DBS需要同时进行记录和刺激，由于持续的刺激伪迹会扭曲潜在的LFP生物标志物，这仍然是一个挑战。在这里，我们首先研究刺激诱发伪迹的性质，并回顾几种已提出的处理它们的技术。然后我们提出一种新方法，使采样时钟与刺激脉冲同步，从而永远不会对刺激伪迹进行采样，同时满足奈奎斯特-香农定理以实现不间断的LFP记录。测试结果表明，该方法在宽频带和宽范围的刺激频率下实现了真正不间断的无伪迹LFP记录。临床意义——这里提出的方法提供了靠近刺激靶点的LFP的连续且无伪迹记录，从而便于使用LFP作为反馈来实施更先进的闭环DBS。
