Displacement characteristics of intraoperative and postoperative positions of electrodes on CT imaging for subthalamic nucleus-deep brain stimulation in Parkinson's disease

Objective To investigate the displacement characteristics of intraoperative and postoperative positions of electrodes on CT imaging for bilateral subthalamic nucleus-deep brain stimulation (STN-DBS) in Parkinson's disease (PD). Methods A retrospective analysis on preoperative MR imaging, intraoperative and postoperative CT images of 35 patients with PD treated with STN-DBS in our hospital from January 2014 to June 2018 was performed. A three-dimensional coordinate system was established based on preoperative MR imaging. MR imaging/CT fusion technique was used to fuse intraoperative and postoperative CT images with preoperative MR imaging to locate intraoperative and postoperative electrode positions. The displacement characteristics of intraoperative and postoperative electrodes were analyzed. Results The spatial distance between intraoperative and postoperative positions of bilateral electrodes was about 1 mm, and the depth displacement was minimal. The postoperative position of the first side electrode on lateral axis was shifted outwardly from intraoperative position, and the second side electrode was shifted internally with a small degree; on anterior-posterior axis, the first side electrode obviously shifted backward, and the second side electrode slightly shifted backward. For bilateral electrodes, corresponding coordinate deviation of three axis between intraoperative electrode-preoperative target and postoperative electrode-preoperative target,showed a significant positive linear correlation, therefore, leading out the coordinate deviation regression function model. Conclusions The displacement of electrodes between intraoperative and postoperative positions has obvious rules after STN-DBS in PD, which can guide the adjustment of intraoperative electrode position and predict the postoperative position of electrode. Key words: Parkinson's disease; Subthalamic nucleus; Deep brain stimulation; Computed tomography image; Electrode location; Displacement