title: Long-term efficacy and safety of chronic globus pallidus internus stimulation in different types of primary dystonia.
abstract: BACKGROUND
  Deep brain stimulation (DBS) of the globus pallidus internus (GPi) offers a very promising therapy for medically intractable dystonia. However, little is known about the long-term benefit and safety of this procedure. We therefore performed a retrospective long-term analysis of 18 patients (age 12-78 years) suffering from primary generalized (9), segmental (6) or focal (3) dystonia (minimum follow-up: 36 months).
  
  
  METHODS
  Outcome was assessed using the Burke-Fahn-Marsden (BFM) scores (generalized dystonia) and the Tsui score (focal/segmental dystonia). Follow-up ranged between 37 and 90 months (mean 60 months).
  
  
  RESULTS
  Patients with generalized dystonia showed a mean improvement in the BFM movement score of 39.4% (range 0-68.8%), 42.5% (range -16.0 to 81.3%) and 46.8% (range -2.7 to 83.1%) at the 3- and 12-month, and long-term follow-up, respectively. In focal/segmental dystonia, the mean reduction in the Tsui score was 36.8% (range 0-100%), 65.1% (range 16.7-100%) and 59.8% (range 16.7-100%) at the 3- and 12-month, and long-term follow-up, respectively. Local infections were noted in 2 patients and hardware problems (electrode dislocation and breakage of the extension cable) in 1 patient.
  
  
  CONCLUSIONS
  Our data showed Gpi-DBS to offer a very effective and safe therapy for different kinds of primary dystonia, with a significant long-term benefit in the majority of cases.
authors.affiliation: Neurochirurgische, Universitätsklinik, Klinikum Grosshadern, Ludwig-Maximilians-Universität München, München, Germany. jan.mehrkens@med.uni-muenchen.de
authors.forename: J H
authors.initials: JH
authors.lastname: Mehrkens
authors.forename: K
authors.initials: K
authors.lastname: Bötzel
authors.forename: U
authors.initials: U
authors.lastname: Steude
authors.forename: K
authors.initials: K
authors.lastname: Zeitler
authors.forename: A
authors.initials: A
authors.lastname: Schnitzler
authors.forename: V
authors.initials: V
authors.lastname: Sturm
authors.forename: J
authors.initials: J
authors.lastname: Voges
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D046690:Deep Brain Stimulation / Q000009:adverse effects / Q000379:methods*; D004185:Disability Evaluation; D020821:Dystonic Disorders / Q000503:physiopathology / Q000628:therapy*; D004566:Electrodes; D005260:Female; D005500:Follow-Up Studies; D005917:Globus Pallidus / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013238:Stereotaxic Techniques / Q000009:adverse effects; D016896:Treatment Outcome; D055815:Young Adult