Kano T, Katayama Y, Kobayashi K, Kasai M, Oshima H, Fukaya C, Yamamoto T
Department of Neurological Surgery, Nihon University School of Medicine, Tokyo, Japan.
Acta Neurochir Suppl. 2006;99:33-5. doi: 10.1007/978-3-211-35205-2_6.
When microelectrode recording of single cell activity is employed for targeting the subthalamic nucleus (STN), multiple sampling of single cells is needed to determine whether the electrode has passed through the ventral boundaries of the STN. In contrast, stepwise recording of multiple cell activities by a semimicroelectrode reveals robust changes in such activities at the dorsal and ventral boundaries. We attempted to quantify changes in multiple cell activities by computing multiple-cell spike density (MSD). We analyzed MSD in 60 sides of 30 patients with Parkinson's disease. Neural noise level was defined as the lowest cut-off level at which neural noise is separated from larger amplitude spikes. MSD was analyzed at cut-off levels ranging from 1.2 to 2.0-fold the neural noise level in the white matter in each trajectory. Both the dorsal and ventral boundaries were clearly identified by an increase and a decrease (p < 0.0001) in MSD, respectively, in all the 60 sides. The cut-off level of 1.2-fold showed the clearest change in MSD between the STN and the pars reticulata of substantia nigra. MSD analysis by semimicroelectrode recording represents the most practical means of identifying the boundaries of STN.
当采用微电极记录单细胞活动来靶向丘脑底核（STN）时，需要对单细胞进行多次采样，以确定电极是否已穿过STN的腹侧边界。相比之下，用半微电极逐步记录多个细胞的活动，可以揭示在背侧和腹侧边界处这些活动的显著变化。我们试图通过计算多细胞峰密度（MSD）来量化多个细胞活动的变化。我们分析了30例帕金森病患者60侧的MSD。神经噪声水平被定义为神经噪声与较大幅度尖峰分离的最低截止水平。在每个轨迹中，在白质中神经噪声水平的1.2至2.0倍的截止水平下分析MSD。在所有60侧中，分别通过MSD的增加和减少（p < 0.0001）清楚地识别出背侧和腹侧边界。1.2倍的截止水平显示出STN与黑质网状部之间MSD的最明显变化。通过半微电极记录进行MSD分析是识别STN边界的最实用方法。
