title: Probabilistic mapping of deep brain stimulation effects in essential tremor.
abstract: To create probabilistic stimulation maps (PSMs) of deep brain stimulation (DBS) effects on tremor suppression and stimulation-induced side-effects in patients with essential tremor (ET).
  
  
  
  Monopolar reviews from 16 ET-patients which consisted of over 600 stimulation settings were used to create PSMs. A spherical model of the volume of neural activation was used to estimate the spatial extent of DBS for each setting. All data was pooled and voxel-wise statistical analysis as well as nonparametric permutation testing was used to confirm the validity of the PSMs.
  
  
  
  PSMs showed tremor suppression to be more pronounced by stimulation in the zona incerta (ZI) than in the ventral intermediate nucleus (VIM). Paresthesias and dizziness were most commonly associated with stimulation in the ZI and surrounding thalamic nuclei.
  
  
  
  Our results support the assumption, that the ZI might be a very effective target for tremor suppression. However stimulation inside the ZI and in its close vicinity was also related to the occurrence of stimulation-induced side-effects, so it remains unclear whether the VIM or the ZI is the overall better target. The study demonstrates the use of PSMs for target selection and evaluation. While their accuracy has to be carefully discussed, they can improve the understanding of DBS effects and can be of use for other DBS targets in the therapy of neurological or psychiatric disorders as well. Furthermore they provide a priori information about expected DBS effects in a certain region and might be helpful to clinicians in programming DBS devices in the future.
authors.affiliation: Department of Neurology, University of Cologne, Cologne, Germany; Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne, Germany.
authors.forename: Till A
authors.initials: TA
authors.lastname: Dembek
authors.affiliation: Department of Neurology, University of Cologne, Cologne, Germany.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Barbe
authors.affiliation: Department of Biomedical Engineering, Linköping University, Linköping, Sweden; Medtronic Neuromodulation, Medtronic Eindhoven Design Center, Eindhoven, The Netherlands.
authors.forename: Mattias
authors.initials: M
authors.lastname: Åström
authors.affiliation: Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne, Germany.
authors.forename: Mauritius
authors.initials: M
authors.lastname: Hoevels
authors.affiliation: Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne, Germany.
authors.forename: Veerle
authors.initials: V
authors.lastname: Visser-Vandewalle
authors.affiliation: Department of Neurology, University of Cologne, Cologne, Germany.
authors.forename: Gereon R
authors.initials: GR
authors.lastname: Fink
authors.affiliation: Department of Neurology, University of Cologne, Cologne, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Timmermann
mesh_terms: D001271:Atlases as Topic; D046690:Deep Brain Stimulation / Q000009:adverse effects / Q000379:methods / Q000706:statistics & numerical data; D004244:Dizziness / Q000209:etiology*; D020329:Essential Tremor / Q000628:therapy*; D006801:Humans; D010292:Paresthesia / Q000209:etiology*; D020651:Ventral Thalamic Nuclei; D065820:Zona Incerta
keywords: DBS, Deep brain stimulation; Deep brain stimulation; ET, Essential tremor; Essential tremor; PSA, Posterior subthalamic area; PSM, Probabilistic stimulation map; Probabilistic mapping; VIM, Ventral intermediate nucleus; VNA, Volume of neural activation; ZI, Zona incerta; Zona incerta