Asleep Robot-Assisted Surgery for the Implantation of Subthalamic Electrodes Provides the Same Clinical Improvement and Therapeutic Window as Awake Surgery.

OBJECTIVE:To study the impact of not performing awake clinical evaluation during the robot-assisted implantation of subthalamic nucleus deep brain stimulation (STN-DBS) electrodes on the stimulation parameters and clinical outcomes in patients with Parkinson disease (PD). METHODS:A total of 23 patients with PD underwent robot-assisted surgery for the bilateral implantation of STN-DBS electrodes. Thirteen patients received general anesthesia (GA) and a limited intraoperative evaluation (side effects only), and the other 10 patients received local anesthesia (LA) and a full evaluation. The primary endpoint was the therapeutic window (TW), defined as the difference between the mean voltage threshold for motor improvement and the mean voltage threshold for side effects in the active contacts at 12 months after surgery. Motor scores were measured as well. RESULTS:The TW was similar in the LA and GA groups, with mean ± standard deviation values of 2.06 ± 0.53 V and 2.28 ± 0.99 V, respectively (P = 0.32). In the short term, the Unified Parkinson Disease Rating Scale (UPDRS) III score in the "off-drug, on-stim" condition fell to a similar extent in the LA and GA groups (by 40.3% and 49%, respectively; P = 0.336), as did the UPDRS III score in the "on-stim, on-drug" condition (by 57% and 70.7%, respectively; P = 0.36). CONCLUSIONS:Asleep, robot-assisted implantation of STN-DBS electrodes (with accurate identification of the STN and positioning of the DBS lead) produced the same motor results and TW as awake surgery.