Objective: The first aim was to compare the preplanned GPi electrode neuroradiological trajectory with the final trajectory selected after electrophysiological monitoring. The second aim was to analyse factors potentially responsible for differences between the preplanned and final trajectories.
Background: Bilateral deep brain stimulation (DBS) of the globus pallidus internus (GPi) is an effective treatment for refractory dystonia. Neuroradiological target and stimulation electrode trajectory planning with intraoperative microelectrode recordings (MER) and stimulation are traditionally used. With improving target delineation, the need for MER is disputed, mainly because of the increased risk of bleeding complications.
Method: Forty patients underwent bilateral GPi DBS surgery (right-sided implants first) for refractory dystonia using frame-based stereotaxy with MER and stimulation. The relationship between the preplanned and final trajectories was correlated with factors characterizing the patient (gender, age, dystonia type and duration) and the surgery (anaesthesia, postoperative pneumocephalus, previous surgery).
Results: The final electrode matched the preplanned trajectory in 72.5% of patients on the right side and 70.0% on the left, with no significant difference in the final electrode position between brain hemispheres. Both electrodes were implanted in the preplanned trajectory in 55% of patients. Contingency tables and one-dimensional binary logistic regression did not confirm any of the studied factors as predictors of the difference between the preplanned and final trajectories.
Conclusion: The final trajectory, modified after electrophysiological study, differed from the preplanned trajectory in a significant percentage of patients, thus supporting the use of MER during DBS surgery. No factor describing the patient, disease, or implantation was identified as a predictor of this difference.
To cite this abstract in AMA style:
J. Kunst, D. Hrabovsky, T. Jurkova, J. Chrastina, M. Balaz. The role of intraoperative electrophysiological monitoring in implanting globus pallidus internus electrodes in patients with dystonia [abstract]. Mov Disord. 2022; 37 (suppl 2). https://www.mdsabstracts.org/abstract/the-role-of-intraoperative-electrophysiological-monitoring-in-implanting-globus-pallidus-internus-electrodes-in-patients-with-dystonia/. Accessed June 15, 2025.« Back to 2022 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/the-role-of-intraoperative-electrophysiological-monitoring-in-implanting-globus-pallidus-internus-electrodes-in-patients-with-dystonia/