Bartels Jess, Andreasen Dinal, Ehirim Princewill, Mao Hui, Seibert Steven, Wright E Joe, Kennedy Philip
Neural Signals Inc., 3400 McClure Bridge Road, Building D, Suite B, Duluth, GA 30096, USA.
J Neurosci Methods. 2008 Sep 30;174(2):168-76. doi: 10.1016/j.jneumeth.2008.06.030. Epub 2008 Jul 10.
The neurotrophic electrode (NE) is designed for longevity and stability of recorded signals. To achieve this aim it induces neurites to grow through its glass tip, thus anchoring it in neuropil. The glass tip contains insulated gold wires for recording the activity of the myelinated neurites that grow into the tip. Neural signals inside the tip are electrically insulated from surrounding neural activity by the glass. The most recent version of the electrode has four wires inside its tip to maximize the number of discriminable signals recorded from ingrown neurites, and has a miniature connector. Flexible coiled, insulated gold wires connect to electronics on the skull that remain subcutaneous. The implanted electronics consist of differential amplifiers, FM transmitters, and a sine wave at power up for tuning and calibration. Inclusion criteria for selecting locked-in subjects include medical stability, normal cognition, and strong caregiver support. The implant target is localized via an fMRI-naming task. Final localization at surgery is achieved by 3D stereotaxic localization. During recording, implanted electronics are powered by magnetic induction across an air gap. Coiled antennas placed on the scalp over the implanted transmitters receive the amplified FM transmitter outputs. Data is processed as described elsewhere where stability and longevity issues are addressed. Five subjects have been successfully implanted with the NE. Recorded signals persisted for over 4 years in two subjects who died from underlying illnesses, and continue for over 3 years in our present subject.
神经营养电极（NE）的设计旨在实现记录信号的长期稳定性。为实现这一目标，它促使神经突通过其玻璃尖端生长，从而将其固定在神经毡中。玻璃尖端包含绝缘金线，用于记录长入尖端的有髓神经突的活动。尖端内部的神经信号通过玻璃与周围神经活动实现电绝缘。该电极的最新版本在其尖端内部有四根电线，以最大限度地增加从长入神经突记录的可分辨信号数量，并且有一个微型连接器。柔性盘绕的绝缘金线连接到颅骨上仍位于皮下的电子设备。植入的电子设备包括差分放大器、调频发射器以及通电时用于调谐和校准的正弦波。选择闭锁综合征患者的纳入标准包括医学稳定性、正常认知和强大的护理人员支持。通过功能磁共振成像命名任务对植入靶点进行定位。手术中的最终定位通过三维立体定位实现。在记录过程中，植入的电子设备通过气隙中的磁感应供电。放置在植入发射器上方头皮上的盘绕天线接收放大后的调频发射器输出。数据按照其他地方所述的方法进行处理，其中涉及稳定性和长期问题。已有五名患者成功植入了NE。在两名因基础疾病死亡的患者中，记录到的信号持续了四年多，在我们目前的患者中持续了三年多。
