Directional deep brain stimulation of the subthalamic nucleus: A pilot study using a novel neurostimulation device

Abstract

Introduction: A novel neurostimulation system allows steering current in horizontal directions by combining segmented leads and multiple independent current control. The aim of this study was to evaluate directional DBS effects on parkinsonian motor features and adverse effects of subthalamic neurostimulation.

Methods: Seven PD patients implanted with the novel directional DBS system for bilateral subthalamic DBS underwent an extended monopolar review session during the first postoperative week, in which current thresholds were determined for rigidity control and stimulation-induced adverse effects using either directional or ring-mode settings.

Results: Effect or adverse effect thresholds were modified by directional settings for each of the 14 STN leads. Magnitude of change varied markedly between leads, as did orientation of optimal horizontal current steering.

Conclusion: Directional current steering through chronically implanted segmented electrodes is feasible, alters adverse effect and efficacy thresholds in a highly individual manner, and expands the therapeutic window in a monopolar review as compared to ring-mode DBS. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Keywords: Parkinson's disease; deep brain stimulation.

Figure 1

Bar graph depicting the relative change of the therapeutic window (%) when steering current in the best vs. worst orientation during the monopolar review. Please note, the change in therapeutic window for best directional current steering was proportionally larger at the less effective ring level. On both levels therapeutic windows assessed for the best orientation of current steering differed significantly from those obtained when stimulating into the worst orientation highlighting a potential clinical usefulness of directional DBS.