Introduction: Since the initial implementation of deep brain stimulation (DBS) for essential tremor by Pollack and Benabid, it has emerged as the gold standard treatment over the past three decades. However, achieving successful outcomes still relies heavily on accurate planning and electrophysiological mapping of the Vim(ventral intermediate nucleus of thalamus). The Vim’s close proximity to sensory nuclei poses a challenge due to the potential for unwanted sensations during stimulation. We started to use thalamus segmentation and probabilistic tractography for targeting in ET and we analised our pateients clinical outcome. We compared our targets coordinates to the standard Shaltenbrad Atlas coordinates in every patinets.

Materials and methods: This study involved 16 patients who underwent preoperative MRI scans, including T1, T2, contrast-enhanced T1, and diffusion tensor imaging (DTI), conducted at two different centers using distinct protocols. Preoperative DTI analysis and fiber tracking were performed utilizing FSL 6.0 and Freesurfer 6.0. Reconstruction of diffusion tensors, probabilistic fiber tracking, and visualization were executed on a Titan XP GPU-based system. Thalamic connectivity segmentation, focusing on identifying sensory nuclei, Vim, and the dentate-rubro-thalamic (DRT) and lemniscal pathways, was integrated into a Medtronic Cranial Planning Station. DBS lead implantation was performed using stereotactic guidance, with intraoperative electrophysiological mapping and macrosimulation to validate imaging findings.

Results: Out of the 32 implanted electrodes, 29 were positioned within a 1 mm range of the DRT, with 65.63% situated within the tract itself. All patients experienced adequate tremor control post-implantation, with no reported sensory side effects during any stage of the procedure. Optimal tremor control was consistently observed near the thalamic entry of the DRT.

Discussion: Visualizing the DRT pathways, sensory nuclei, and lemniscal pathways facilitates a personalized approach to DBS surgery. Relying solely on standard stereotactic coordinates may result in unintended side effects because of sensory activation during stimulation. We experienced this approach not only ensures effective tremor control but also reduces the likelihood of suboptimal lead placement of the individual patients.