IEEE Trans Neural Syst Rehabil Eng. 2019 Sep;27(9):1724-1731. doi: 10.1109/TNSRE.2019.2932032. Epub 2019 Jul 31.
Reliable chronic neural recording from focal deep brain structures is impeded by insertion injury and foreign body response, the magnitude of which is correlated with the mechanical mismatch between the electrode and tissue. Thin and flexible electrodes cause less glial scarring and record longer than stiff electrodes. However, the insertion of flexible microelectrodes in brain has been a challenge. Here, a novel insertion method is proposed, and demonstrated, for precise targeting deep brain structures using flexible micro-wire electrodes. The microelectrode is spun and slowly inserted in brain through an appropriate electrode guide. The electrode guide does not penetrate into cortex. Based on two new mechanisms, namely spinning and guided insertion, we have demonstrated successful insertion of 25-micron platinum flexible electrodes about 10-mm deep in rat brains without buckling. We present an electrode insertion device based on the proposed method and demonstrate its use to implant flexible microelectrodes in rat brains. The step-by-step insertion process is described. Microelectrodes were inserted in the Bötzinger complex and respiratory neural activity was recorded acutely in nine rats and chronically in two rats for 50 days.
可靠的深部脑结构的慢性神经记录受到插入损伤和异物反应的阻碍，其程度与电极和组织之间的机械不匹配有关。薄而灵活的电极引起的神经胶质瘢痕较少，记录时间也比刚性电极长。然而，柔性微电极在大脑中的插入一直是一个挑战。在这里，提出并验证了一种新的插入方法，使用柔性微丝电极精确靶向深部脑结构。微电极通过适当的电极引导旋转并缓慢插入大脑。电极引导不穿透皮层。基于旋转和引导插入这两个新机制，我们已经成功地将 25 微米的铂柔性电极插入大鼠大脑约 10 毫米深，而没有出现弯曲。我们提出了一种基于该方法的电极插入装置，并演示了其在大鼠大脑中植入柔性微电极的用途。描述了逐步插入过程。在 9 只大鼠中进行了急性记录，在 2 只大鼠中进行了 50 天的慢性记录，微电极插入了 Botzinger 复合体中，并记录了呼吸神经活动。
