Deep brain stimulation electrodes may rotate after implantation-an animal study

Directional deep brain stimulation (dDBS) electrodes allow to steer the electrical field in a specific direction. When implanted with torque, they may rotate for a certain time after implantation. The aim of this study was to evaluate whether and to which degree leads rotate in the first 24 h after implantation using a sheep brain model. dDBS electrodes were implanted in 14 sheep heads and 3D rotational fluoroscopy (3D-RF) scans were acquired to visualize the orientation of the electrode leads. Electrode leads were clockwise rotated just above the burr holes (180 degrees n = 6, 360 degrees n = 6, 2 controls) and 3D-RF scans were again acquired after 3, 6, 13, 17, and 24 h, respectively. One hundred eighty degree rotated electrodes showed an initial rotation of 83.5 degrees (range: 35.4 degrees-128.3 degrees) and a rotation of 114.0 degrees (range: 57 degrees-162 degrees) after 24 h. With 360 degrees torsion, mean initial rotation was 201 degrees (range: 3.3 degrees-321.4 degrees) and mean rotation after 24 h 215.7 degrees (range 31.9 degrees-334.7 degrees), respectively. Direct postoperative imaging may not be accurate for determining the rotation of dDBS electrodes if torque is present.

Automated summary

Using a sheep brain model, this study found that dDBS electrodes may rotate after implantation, with the rotation degree related to the applied torque. Immediate postoperative imaging may not accurately assess the rotation of the electrodes.