Department of Neurological Surgery, Oregon Health and Science University, Portland, Oregon, USA,
Neurosurgery, University of Kansas Medical Center, Kansas City, Kansas, USA.
Stereotact Funct Neurosurg. 2020;98(1):37-42. doi: 10.1159/000505494. Epub 2020 Feb 4.
Electromagnetic (EM) localization has typically been used to direct shunt catheters into the ventricle. The objective of this study was to determine if this method of EM tracking could be used in a deep brain stimulation (DBS) electrode cannula to accurately predict the eventual location of the electrode contacts.
The Medtronic AxiEMTM system was used to generate the cannula tip location directed to the planned target site. Prior to clinical testing, a series of phantom modelling observations were made.
Phantom trials (n = 23) demonstrated that the cannula tip could be accurately located at the target site with an error of between 0.331 ± 0.144 and 0.6 ± 0.245 mm, depending on the orientation of the delivery system to the axis of the phantom head. Intraoperative EM localization of the DBS cannula was performed in 84 trajectories in 48 patients. The average difference between the planned target and the EM stylet location at the cannula tip was 1.036 ± 0.543 mm. The average error between the planned target coordinates and the actual target electrode location (by CT) was 1.431 ± 0.607 and 1.145 ± 0.636 mm for the EM stylet location in the cannula (p = 0.00312), indicating that EM localization reflected the position of the target electrode more accurately than the planned target.
EM localization can be used to verify the position of DBS electrodes intraoperatively with a high accuracy.
电磁（EM）定位通常用于将分流导管引导至心室。本研究的目的是确定这种 EM 跟踪方法是否可用于深部脑刺激（DBS）电极套管，以准确预测电极接触的最终位置。
使用 Medtronic AxiEMTM 系统生成指向计划靶区的套管尖端位置。在临床测试之前，进行了一系列的幻影模型观察。
幻影试验（n=23）表明，套管尖端可以在目标部位精确定位，误差在 0.331±0.144 至 0.6±0.245mm 之间，这取决于输送系统相对于幻影头部轴的方向。在 48 名患者的 84 条轨迹中进行了 DBS 套管的术中 EM 定位。计划靶区与 EM 引导针在套管尖端的位置之间的平均差异为 1.036±0.543mm。计划靶区坐标与实际目标电极位置（通过 CT）之间的平均误差为 1.431±0.607mm 和 1.145±0.636mm，这是 EM 引导针在套管中的位置（p=0.00312），这表明 EM 定位比计划靶区更能准确反映目标电极的位置。
EM 定位可用于术中验证 DBS 电极的位置，具有很高的准确性。
