Low-frequency repetitive transcranial magnetic stimulation to the temporoparietal junction for tinnitus

Abstract

Objective: To examine the effectiveness and safety of low-frequency repetitive transcranial magnetic stimulation (rTMS) to the temporoparietal junction in a cohort of patients with bothersome tinnitus.

Design: Crossover, double-blind, randomized clinical trial.

Setting: Outpatient academic medical center.

Participants: Fourteen adults aged 42 to 59 years with subjective, unilateral or bilateral, nonpulsatile tinnitus of 6 months' duration or longer and a score of 38 or greater on the Tinnitus Handicap Inventory (THI).

Interventions: Low-frequency (1-Hz) 110% motor threshold rTMS or sham treatment to the left temporoparietal junction for 2 weeks.

Main outcome measure: The difference in the change of the THI score between active and sham rTMS.

Results: Active treatment was associated with a median (95% confidence interval) reduction in THI score of 5 (0-14) points, and sham treatment was associated with a median reduction in THI score of 6 (-2 to 12) points. The difference in THI scores between the change associated with active and sham rTMS ranged from a 34-point reduction in THI score after active treatment to a 22-point increase after sham treatment, with a median difference change of only 1 point (-6 to 4 points).

Conclusions: Daily low-frequency rTMS to the left temporoparietal junction area for 2 weeks is no more effective than placebo for patients with chronic bothersome tinnitus. Possible explanations for the negative findings are short duration of treatment, failure of rTMS stimulation over the temporoparietal area to affect the auditory cortex buried within the Sylvian fissure, or more widespread cortical network changes associated with severe bothersome tinnitus not amenable to localized rTMS effects. Trial Registration clinicaltrials.gov Identifier: NCT00567892.

Figures

Figure 1

Sagital MRI View With Marker Overlying Left Temporoparietal Junction.

Figure 2

Flow Diagram of Participation.

Figure 3

Box And Whisker Plot Of Change In THI Score Footnote: Asterisks report mean, horizontal black line represents median, and upper and lower boundaries of box represent 75th and 25th percentile. Horizontal dash and solid lines represent statistical and clinical significant levels, respectively. Vertical line represents 95% confidence interval for the median.

Figure 4

Comparison of Patient’s Global Impression of Change Post-Active and Post-Sham Treatment.

Figure 5

Comparison of Patients’ Response to the question “Please Indicate The Overall Amount Of Disturbance Or "Bother" That You Experience In Your Life As A Result Of Your Tinnitus” at Different Time-Points in the Study.