title: Short duration repetitive transcranial magnetic stimulation for tinnitus treatment: a prospective Asian study.
abstract: BACKGROUND
  Tinnitus is a subjective auditory perception of sounds or noise not triggered by external auditory stimuli. To date, treatment in severe cases is generally unsatisfactory. Characteristic functional brain imaging changes associated with tinnitus include hyperactivity encompassing both the primary auditory cortex (AC) and the secondary or associative cortex. Brief repetitive transcranial magnetic stimulation (rTMS) trains applied to the scalp overlying the hyperactive left AC is known to produce moderate tinnitus attenuation.
  
  
  OBJECTIVE
  Although Western studies have documented the value of rTMS in tinnitus treatment, we evaluate the efficacy of a short duration rTMS protocol for the first time in the Asian setting.
  
  
  METHODS
  Consecutive patients were recruited at our tinnitus clinic. Detailed history, examination, audiogram and baseline tinnitus scales were recorded. RTMS consisted of 1000 pulses/day at 1 Hz and 110% of the motor threshold, for five consecutive days over the left temporoparietal cortex. Tinnitus ratings were determined weekly for 4 weeks after rTMS.
  
  
  RESULTS
  Fifteen patients completed the trial; none experienced significant side effects. Repeated measures ANOVA showed significant linear decrease in Tinnitus Handicap Inventory (THI) scores over the time period (F((1,14))=4.7, p=0.04). However, none of the other parameters (severity, annoyance, effect on lifestyle and overall impression: visual analogue scale) showed beneficial outcomes.
  
  
  CONCLUSIONS
  Our findings point to a positive effect of short duration rTMS in tinnitus treatment using the THI. However, no significant benefits were demonstrated for other subjective patient ratings. Although well tolerated and convenient, short duration rTMS may prove inadequate for modulating maladaptive plastic changes at the cortical level, and our results suggest the need for delivery of more stimuli. Future studies will utilize at least 2000 pulses/day, in line with previous experience in Western settings.
authors.affiliation: Department of Neurology, National Neuroscience Institute, Singapore General Hospital, Outram Road, Singapore 169608, Singapore. simon.ting.k.s@sgh.com.sg
authors.forename: S K S
authors.initials: SK
authors.lastname: Ting
authors.forename: Y M
authors.initials: YM
authors.lastname: Chan
authors.forename: P W T
authors.initials: PW
authors.lastname: Cheong
authors.forename: M
authors.initials: M
authors.lastname: Wong
authors.forename: S
authors.initials: S
authors.lastname: Fook-Chong
authors.forename: Y L
authors.initials: YL
authors.lastname: Lo
mesh_terms: D044466:Asian People; D002540:Cerebral Cortex / Q000502:physiology; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012846:Singapore; D014012:Tinnitus / Q000175:diagnosis / Q000628:therapy*; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D016896:Treatment Outcome