Safety and Feasibility of Transcranial Motor-Evoked Potentials During Intraoperative Neurophysiologic Monitoring in Patients With Deep Brain Stimulators

PURPOSE: Transcranial motor-evoked potentials (TcMEPs) are routinely used for intraoperative neurophysiologic monitoring to assess corticospinal tract integrity. However, data regarding the use of TcMEPs in patients with implanted deep brain stimulator (DBS) devices remain limited. This study aims to evaluate the safety and feasibility of TcMEP monitoring in patients with implanted DBS systems undergoing a variety of surgical procedures. METHODS: A retrospective review was conducted using clinical and neurophysiologic data from patients with DBS devices who underwent surgery with TcMEP monitoring at a single institution between 2014 and 2024. Patient demographics, surgical and device information, TcMEP stimulation parameters, and intraoperative neurophysiologic monitoring documentation, as well as intraoperative and postoperative clinical notes were reviewed. RESULTS: Sixteen patients were identified who underwent 19 surgical procedures with TcMEP monitoring. Reliable TcMEP signals were successfully obtained in all patients across a variety of surgical procedures, DBS targets, and stimulation parameters (80-520 V, 147-1,388 mA). No TcMEP-related intraoperative or postoperative complications were identified, and DBS device functionality remained preserved. However, active DBS stimulation during surgery generated electrical artifacts that interfered with other intraoperative neurophysiologic monitoring modalities, including somatosensory evoked potentials and EEG (electroencephalogram). CONCLUSIONS: Transcranial motor-evoked potentials monitoring is safe and feasible in patients with implanted DBS devices undergoing a variety of surgical procedures. Standard TcMEP stimulation parameters can be implemented without significant modification. To minimize interference with multimodal intraoperative neurophysiologic monitoring, DBS devices should be turned off during monitoring. Further studies are needed to establish standardized guidelines for TcMEP monitoring in patients with DBS and other intracranial neurostimulation devices.