title: Chronic bilateral pallidal stimulation in patients with generalized primary dystonia - multi-contact cathodal stimulation is superior to bipolar stimulation mode. Preliminary results.
abstract: OBJECTIVE
  Primary generalized dystonia (PGD) is a medically refractory progressive disease of the brain causing near total handicap of affected patients. The aim of the study was to assess the efficacy and safety of bilateral pallidal stimulation in patients with PGD.
  
  
  METHODS
  The study population is composed of 5 patients with PGD. The formal objective assessment included the Burke-Fahn-Marsden dystonia rating scale (BFMDRS). All stereotactic procedures were performed in general anaesthesia using a Leksell G stereotactic head frame without electrophysiological guidance. Immediately after insertion of deep brain stimulation (DBS) leads, the internal pulse generators (Itrel II or Soletra) were implanted subcutaneously in the chest wall or abdominal region.
  
  
  RESULTS
  There were no complications related to the stereotactic procedures. The hardware-related complications (two broken DBS leads) were replaced successfully. There were no infections or erosions of implanted hardware. It has been observed that in the long-term follow-up period primary set bipolar stimulation mode lost its benefit achieved previously. Various stimulation combinations were investigated. Monopolar cathodal or especially multi-contact cathodal stimulation was the most effective one. The efficacy of bilateral pallidal stimulation was proved by the objective validated BFMDRS at long-term follow-up.
  
  
  CONCLUSIONS
  Response to DBS may improve with the number of activated cathodal contacts within the globus pallidus internus.
authors.affiliation: Klinika Neurochirurgii, Centrum Medyczne Kształcenia Podyplomowego, ul. Marymoncka 99, Warszawa. mrsob@op.pl
authors.forename: Michał
authors.initials: M
authors.lastname: Sobstyl
authors.forename: Mirosław
authors.initials: M
authors.lastname: Ząbek
authors.forename: Sebastian
authors.initials: S
authors.lastname: Dzierzęcki
authors.forename: Henryk
authors.initials: H
authors.lastname: Koziara
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Mossakowski
mesh_terms: D000328:Adult; D046690:Deep Brain Stimulation / Q000295:instrumentation / Q000379:methods*; D020821:Dystonic Disorders / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D005917:Globus Pallidus / Q000503:physiopathology*; D006801:Humans; D058542:Implantable Neurostimulators; D008297:Male; D019635:Neurosurgical Procedures / Q000295:instrumentation* / Q000379:methods; D020127:Recovery of Function; D012720:Severity of Illness Index; D016896:Treatment Outcome; D055815:Young Adult