title: Effect of chronic cortical stimulation on chronic severe tinnitus: a prospective randomized double-blind cross-over trial and long-term follow up.
abstract: BACKGROUND
  Chronic severe tinnitus can be greatly detrimental to quality of life. Some authors have reported benefit of repetitive transcranial magnetic stimulation, others of electrical cortical stimulation by stimulating the Heschl's gyrus or secondary auditory areas.
  
  
  OBJECTIVE
  To evaluate the efficacy of chronic electrical epidural stimulation of the auditory cortex on severe and disabling tinnitus.
  
  
  METHODS
  In this double-blind randomized cross-over, patients with chronic (at least 2 years), severe (Strukturierte Tinnitus-Interview, STI score > 19), unilateral or strongly lateralized tinnitus were included. After open-phase stimulation for 4 months, patients were randomized into 2 groups for double-blind stimulation with cross-over between significant and non-significant phases and wash-out in between. Each of the 3 phases was 2 weeks in duration. Patients were chronically stimulated and followed if not explanted. A decrease of STI score >35% was considered as clinically significant.
  
  
  RESULTS
  None of the 9 patients included achieved significant improvement during the double-blind phase. Four were explanted, 2 owing to lack of effect, one for breast cancer under the stimulator, and another for psychiatric decompensation. Five are still stimulated. Three felt slight to great subjective effectiveness, the remaining 2 reported benefits and still requested stimulation.
  
  
  CONCLUSIONS
  This study did not find an objective efficiency of chronic cortical stimulation for severe and resistant tinnitus. The discordance between the results in double-blind and open evaluations could be related to a placebo effect of surgery, but may also be explained by a poorly defined target, a too short randomized phase, or inappropriate outcome measures. Clinical trial reference: NCT00486577.
authors.affiliation: CHU Bordeaux, Service de Neurochirurgie, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Engelhardt
authors.affiliation: CHU Bordeaux, Service d'Oto-Rhino-Laryngologie, France; University of Bordeaux, France.
authors.forename: René
authors.initials: R
authors.lastname: Dauman
authors.affiliation: CHU Bordeaux, Service d'Exploration Fonctionnelle Neurologique, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Arné
authors.affiliation: University of Bordeaux, INCIA, UMR 5287 and CNRS, INCIA, UMR 5287, France.
authors.forename: Michèle
authors.initials: M
authors.lastname: Allard
authors.affiliation: University of Poitiers, CAPS-EA4050, Department of Psychology, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Dauman
authors.affiliation: CHU Bordeaux, Service de Neurochirurgie, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Branchard
authors.affiliation: CHU Bordeaux, Unité de Soutien Méthodologique à la Recherche Clinique (USMR), Pôle de Santé Publique, France.
authors.forename: Paul
authors.initials: P
authors.lastname: Perez
authors.affiliation: CHU Bordeaux, Unité de Soutien Méthodologique à la Recherche Clinique (USMR), Pôle de Santé Publique, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Germain
authors.affiliation: CHU Limoges Service de Neurochirurgie, and ERMA, Univ. Limoges, France.
authors.forename: François
authors.initials: F
authors.lastname: Caire
authors.affiliation: CHU Bordeaux, Service d'Oto-Rhino-Laryngologie, France; University of Bordeaux, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Bonnard
authors.affiliation: CHU Bordeaux, Service de Neurochirurgie, France; University of Bordeaux, France. Electronic address: emmanuel.cuny@chu-bordeaux.fr.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Cuny
mesh_terms: D000328:Adult; D000368:Aged; D001303:Auditory Cortex / Q000503:physiopathology; D002908:Chronic Disease; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015990:Placebo Effect; D011446:Prospective Studies; D012720:Severity of Illness Index; D014012:Tinnitus / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy*; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D016896:Treatment Outcome
keywords: Auditory evoked potentials; Cortical stimulation; Functional MRI; Heschl's gyrus; Tinnitus