title: Thalamotomy as a treatment option for tremor after ineffective deep brain stimulation.
abstract: BACKGROUND
  As the number of deep brain stimulation (DBS) surgeries increases, complications from malpositioned electrodes, tolerance to stimulation and loss of efficacy have also increased. Our objective was to assess thalamotomy as a salvage treatment option after ineffective DBS.
  
  
  METHODS
  A retrospective chart analysis of patients who underwent ipsilateral stereotactic thalamotomy after an ineffective ventrointermediate nucleus DBS procedure was undertaken. Patient outcome was based on follow-up visit chart notes, and a nonvalidated patient telephone questionnaire to assess patients' perception of tremor and functional ability after thalamotomy.
  
  
  RESULTS
  Six patients with essential tremor and 1 with tremor-predominant Parkinson's disease met our inclusion criteria. Thalamotomies were undertaken for ineffective DBS due to dysarthria and paresthesias with programming in 2 patients, tremor that failed to respond to increased DBS despite a lack of side effects in 2 patients, malpositioned electrode in 2 patients, and sudden loss of DBS efficacy following eye surgery in 1 patient. Following thalamotomy, 3 patients reported improvement in symptoms and function, 3 patients reported improvement in symptoms that were not reflected in functional improvement, and 1 patient reported no improvement in symptoms or function.
  
  
  CONCLUSIONS
  Thalamotomy may provide a viable salvage solution in patients who fail to respond to DBS due to complications such as malpositioned electrodes, tolerance to stimulation or loss of efficacy.
authors.affiliation: Department of Neurological Surgery, Oregon Health & Science University, Portland, OR 97239, USA.
authors.forename: Diaa
authors.initials: D
authors.lastname: Bahgat
authors.forename: Stephen T
authors.initials: ST
authors.lastname: Magill
authors.forename: Caglar
authors.initials: C
authors.lastname: Berk
authors.forename: Shirley
authors.initials: S
authors.lastname: McCartney
authors.forename: Kim J
authors.initials: KJ
authors.lastname: Burchiel
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D046690:Deep Brain Stimulation; D020329:Essential Tremor / Q000601:surgery* / Q000628:therapy; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009422:Nervous System Diseases / Q000209:etiology; D010300:Parkinson Disease / Q000601:surgery* / Q000628:therapy; D011183:Postoperative Complications / Q000209:etiology; D012189:Retrospective Studies; D016879:Salvage Therapy; D013238:Stereotaxic Techniques; D025321:Surgery, Computer-Assisted; D011795:Surveys and Questionnaires; D013788:Thalamus / Q000601:surgery*; D016896:Treatment Outcome