title: Directional steering: A novel approach to deep brain stimulation.
abstract: OBJECTIVE
  The aim of this study was to investigate whether directional steering through a novel 32-contact electrode is safe and can modulate the thresholds for beneficial and side effects of stimulation.
  
  
  METHODS
  The study is a single-center, performance and safety study. Double-blind intraoperative evaluations of the thresholds for therapeutic benefit and for side effects were performed in 8 patients with Parkinson disease while stimulating in randomized order in spherical mode and in 4 different steering modes with the 32-contact electrode, and in monopolar mode with a commercial electrode. In addition, simultaneous recordings of local field potentials through all 32 contacts were performed.
  
  
  RESULTS
  There were no adverse events related to the experimental device. For 13 of 15 side effects (87%), the threshold could be increased by ≥ 1 mA while steering in at least one direction in comparison to conventional spherical stimulation, thereby increasing the therapeutic window by up to 1.5 mA. Recording local field potentials through all 32 electrode contacts yielded spatiotemporal information on pathologic neuronal activity.
  
  
  CONCLUSIONS
  Controlled steering of current through the brain may improve the effectiveness of deep brain stimulation (DBS), allow for novel applications, and provide a tool to better explore pathophysiologic activity in the brain.
  
  
  METHODS
  This study provides Class IV evidence that for patients with Parkinson disease, steering DBS current is well tolerated, increases the threshold for side effects, and may improve the therapeutic window of subthalamic nucleus DBS as compared with current standard spherical stimulation.
authors.affiliation: From the Departments of Neurology/Clinical Neurophysiology (M.F.C., L.J.B., R.V., M.A.J.L., R.M.A.d.B.) and Neurosurgery (P.v.d.M., P.R.S.), Academic Medical Center, University of Amsterdam, the Netherlands; and Department of Neurology (M.F.C.), Haga Teaching Hospital, The Hague, the Netherlands. p.r.schuurman@amc.nl m.f.contarino@amc.uva.nl.
authors.forename: M Fiorella
authors.initials: MF
authors.lastname: Contarino
authors.affiliation: From the Departments of Neurology/Clinical Neurophysiology (M.F.C., L.J.B., R.V., M.A.J.L., R.M.A.d.B.) and Neurosurgery (P.v.d.M., P.R.S.), Academic Medical Center, University of Amsterdam, the Netherlands; and Department of Neurology (M.F.C.), Haga Teaching Hospital, The Hague, the Netherlands.
authors.forename: Lo J
authors.initials: LJ
authors.lastname: Bour
authors.affiliation: From the Departments of Neurology/Clinical Neurophysiology (M.F.C., L.J.B., R.V., M.A.J.L., R.M.A.d.B.) and Neurosurgery (P.v.d.M., P.R.S.), Academic Medical Center, University of Amsterdam, the Netherlands; and Department of Neurology (M.F.C.), Haga Teaching Hospital, The Hague, the Netherlands.
authors.forename: Rens
authors.initials: R
authors.lastname: Verhagen
authors.affiliation: From the Departments of Neurology/Clinical Neurophysiology (M.F.C., L.J.B., R.V., M.A.J.L., R.M.A.d.B.) and Neurosurgery (P.v.d.M., P.R.S.), Academic Medical Center, University of Amsterdam, the Netherlands; and Department of Neurology (M.F.C.), Haga Teaching Hospital, The Hague, the Netherlands.
authors.forename: Marcel A J
authors.initials: MA
authors.lastname: Lourens
authors.affiliation: From the Departments of Neurology/Clinical Neurophysiology (M.F.C., L.J.B., R.V., M.A.J.L., R.M.A.d.B.) and Neurosurgery (P.v.d.M., P.R.S.), Academic Medical Center, University of Amsterdam, the Netherlands; and Department of Neurology (M.F.C.), Haga Teaching Hospital, The Hague, the Netherlands.
authors.forename: Rob M A
authors.initials: RM
authors.lastname: de Bie
authors.affiliation: From the Departments of Neurology/Clinical Neurophysiology (M.F.C., L.J.B., R.V., M.A.J.L., R.M.A.d.B.) and Neurosurgery (P.v.d.M., P.R.S.), Academic Medical Center, University of Amsterdam, the Netherlands; and Department of Neurology (M.F.C.), Haga Teaching Hospital, The Hague, the Netherlands.
authors.forename: Pepijn
authors.initials: P
authors.lastname: van den Munckhof
authors.affiliation: From the Departments of Neurology/Clinical Neurophysiology (M.F.C., L.J.B., R.V., M.A.J.L., R.M.A.d.B.) and Neurosurgery (P.v.d.M., P.R.S.), Academic Medical Center, University of Amsterdam, the Netherlands; and Department of Neurology (M.F.C.), Haga Teaching Hospital, The Hague, the Netherlands. p.r.schuurman@amc.nl m.f.contarino@amc.uva.nl.
authors.forename: P R
authors.initials: PR
authors.lastname: Schuurman
mesh_terms: D000328:Adult; D046690:Deep Brain Stimulation; D004311:Double-Blind Method; D004566:Electrodes; D006801:Humans; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology* / Q000628:therapy*; D016896:Treatment Outcome