Electrocorticography During Deep Brain Stimulation Surgery for Movement Disorders: Single-Center Experience

Objective: Electrocorticography can serve as an intraoperative research tool during deep brain stimulation procedure, when patients are awake to participate in behavioral tasks or to allow recordings while awake but at rest. This report aims to describe the electrocorticography methods used in awake patients undergoing deep brain stimulation surgery at a single center and to describe the feasibility, safety, and usefulness of high-density electrocorticography for capturing high-resolution neurophysiological data during deep brain stimulation surgery. We hypothesize that the use of high-density electrocorticography and multi-subject integration of cortical data enables improved spatial resolution and data analysis compared to prior studies employing lower-density electrodes and primarily single-subject analyses. Methods: Data were obtained from patients undergoing awake deep brain stimulation surgery for the treatment of Parkinson's disease or essential tremor at Johns Hopkins Hospital between March 2022 and September 2024. Electrophysiological and anatomical data were analyzed, with localization in the anterior commissure and posterior commissure and Montreal Neurological Institute coordinate systems. Surgical complications were monitored for at least six months postoperatively. Results: Thirty-six patients (26 with Parkinson's disease, 10 with essential tremor) were enrolled in the study. In one case, anatomical placement was inadequate for neurophysiological analysis. Postoperative complications included three infections (8.3%) and one chronic subdural hematoma (2.8%), with no permanent neurological deficits. Observed complication rates were within the range reported in the literature for standard deep brain stimulation surgeries without electrocorticography. Anatomical and neurophysiological analysis demonstrated high-resolution cortical mapping. Multiple-subject level analysis using high-density electrocorticography yielded over 1300 electrode positions. Conclusions: Electrocorticography during deep brain stimulation is a valuable research method for movement disorders and, based on a moderate sized consecutive clinic sample, appears safe with risks no greater than those associated with DBS surgery itself.