title: Deep Brain Stimulation of the internal globus pallidus in refractory Tourette Syndrome.
abstract: OBJECTIVE
  Deep Brain Stimulation in psychiatric disorders is becoming an increasingly performed surgery. At present, seven different targets have been stimulated in Tourette Syndrome, including the internal globus pallidus. We describe the effects on tics and comorbid behavioral disorders of Deep Brain Stimulation of the anterior internal globus pallidus in five patients with refractory Tourette Syndrome.
  
  
  METHODS
  This study was performed as an open label study with follow-up assessment between 12 and 38 months. Patients were evaluated twice, one month before surgery and at long-term follow-up. Primary outcome was tic severity, assessed by several scales. Secondary outcomes were comorbid behavioral disorders, mood and cognition. The final position of the active contacts of the implanted electrodes was investigated and side effects were reported.
  
  
  RESULTS
  Three males and two females were included with a mean age of 41.6 years (SD 9.7). The total post-operative score on the Yale Global Tic Severity Scale was significantly lower than the pre-operative score (42.2±4.8 versus 12.8±3.8, P=0.043). There was also a significant reduction on the modified Rush Video-Based Tic Rating Scale (13.0±2.0 versus 7.0±1.6, P=0.041) and in the total number of video-rated tics (259.6±107.3 versus 49.6±24.8, P=0.043). No significant difference on the secondary outcomes was found, however, there was an improvement on an individual level for obsessive-compulsive behavior. The final position of the active contacts was variable in our sample and no relationship between position and stimulation effects could be established.
  
  
  CONCLUSIONS
  Our study suggests that Deep Brain Stimulation of the anterior internal globus pallidus is effective in reducing tic severity, and possibly also obsessive-compulsive behavior, in refractory Tourette patients without serious adverse events or side-effects.
authors.affiliation: Departments of Neurosurgery, Maastricht University Medical Center, Maastricht, The Netherlands; Departments of Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands. Electronic address: anouk.smeets@mumc.nl.
authors.forename: A Y J M
authors.initials: AYJM
authors.lastname: Smeets
authors.affiliation: Departments of Psychiatry and Psychology, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: A A
authors.initials: AA
authors.lastname: Duits
authors.affiliation: Biomedical Image Analysis, Eindhoven University of Technology, Eindhoven, The Netherlands.
authors.forename: B R
authors.initials: BR
authors.lastname: Plantinga
authors.affiliation: Departments of Psychiatry and Psychology, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: A F G
authors.initials: AFG
authors.lastname: Leentjens
authors.affiliation: Departments of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Oosterloo
authors.affiliation: Department of Stereotactic and Functional Neurosurgery, University of Cologne, Cologne, Germany.
authors.forename: V
authors.initials: V
authors.lastname: Visser-Vandewalle
authors.affiliation: Departments of Neurosurgery, Maastricht University Medical Center, Maastricht, The Netherlands; Departments of Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: Y
authors.initials: Y
authors.lastname: Temel
authors.affiliation: Departments of Neurosurgery, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: L
authors.initials: L
authors.lastname: Ackermans
mesh_terms: D000328:Adult; D046690:Deep Brain Stimulation; D004567:Electrodes, Implanted; D005260:Female; D005500:Follow-Up Studies; D005917:Globus Pallidus / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D020323:Tics / Q000601:surgery*; D005879:Tourette Syndrome / Q000503:physiopathology / Q000628:therapy*; D016896:Treatment Outcome
keywords: Deep Brain Stimulation; Internal globus pallidus; Obsessive–compulsive behavior; Refractory; Tic reduction; Tourette Syndrome