Individualized Anatomy-Based Targeting for VIM-cZI DBS in Essential Tremor.

ABSTRACT Background Deep Brain Stimulation (DBS) of the ventral intermediate nucleus (VIM) or caudal Zona Incerta (cZI) is effective for refractory essential tremor (ET). To refine stereotactic planning for lead placement, we developed a unique individualized anatomy-based planning protocol that targets both the VIM and the cZI in patients with ET. Methods 33 ET patients underwent VIM-cZI lead implantation with targeting based on our protocol. Indirect targeting was adjusted based on anatomic landmarks as reference lines bisecting the red nuclei and ipsilateral subthalamus. Outcomes were evaluated through the follow-up of 31.1 ±18.4 months. Active contact coordinates were obtained from reconstructed electrodes in MNI space using the Matlab Lead-DBS toolbox. Results Mean tremor improvement was 79.7 ±22.4% and remained stable throughout the follow-up period. Active contacts at last post-operative visit had mean MNI coordinates of 15.5 ± 1.6 mm lateral to intercommissural line, 15.3 ± 1.8 mm posterior to AC, and 1.4 ± 2.9 mm below intercommissural plane. No hemorrhagic complications were observed in the analyzed group. Conclusion Individualized anatomy-based VIM-cZI targeting is feasible, safe and is associated with favorable tremor outcomes.