title: Surgical therapy for multiple sclerosis tremor: a 12-year follow-up study.
abstract: OBJECTIVE
  Severe multiple sclerosis (MS) tremor causes disability poorly responsive to medication. Deep brain stimulation (DBS) or thalamotomy can suppress tremor, but long-term outcomes are unclear.
  
  
  METHODS
  Nine patients with MS tremor underwent disability measures at baseline and 12 months post-surgery (six thalamotomy, three DBS) in 1997-1998 (previously reported, Matsumoto et al., Neurology 2001;57:1876-82). We report the prospective 12-year follow-up of this cohort for tremor, disability, and death.
  
  
  RESULTS
  Surgery was initially successful in all. Tremor recurred in all patients within median 3 months, although two DBS patients were tremor-free for 5 years. Median tremor-free survival (tremor-free time/survival time) was 4.3%. At 12-year follow-up, four survivors (two thalamotomy, two DBS) (Expanded Disability Status Scale scores 8-8.5) were severely disabled. Five patients were dead (four thalamotomy, one DBS) median 5.8 years post-operative.
  
  
  CONCLUSIONS
  Surgery benefit for severe tremor was overall short-lived (median 3 months), with long-term poor prognosis. Although two DBS patients had sustained 5-year tremor-suppression, the observed progressive disability and death in this cohort bear importance for long-term success in future MS tremor surgery trials.
authors.affiliation: Department of Neurology, Mayo Clinic, Rochester, MN, USA.
authors.forename: A
authors.initials: A
authors.lastname: Hassan
authors.forename: J E
authors.initials: JE
authors.lastname: Ahlskog
authors.forename: M
authors.initials: M
authors.lastname: Rodriguez
authors.forename: J Y
authors.initials: JY
authors.lastname: Matsumoto
mesh_terms: D000328:Adult; D046690:Deep Brain Stimulation / Q000379:methods; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications / Q000628:therapy*; D011612:Psychosurgery / Q000379:methods*; D012189:Retrospective Studies; D013788:Thalamus / Q000502:physiology; D016896:Treatment Outcome; D014202:Tremor / Q000150:complications / Q000601:surgery*