Publication:

Protocol for a triple-blinded randomised sham-controlled pilot trial of multi-session transcranial direct current stimulation for tinnitus alleviation: the WHITBY study

Background Tinnitus-the perception of sound in the absence of an external source is a common condition, highly impactful condition for which treatment options are limited. Based on the limited available evidence, transcranial direct current stimulation (tDCS) has shown promise for suppressing, or reducing, tinnitus salience. Unlike existing tinnitus interventions, which aim to help patients to better cope with tinnitus, tDCS has the potential to address the tinnitus percept itself.

Methods Protocol for a triple-blinded randomised sham-controlled pilot trial, aimed at informing a future clinical trial for tDCS-based tinnitus treatment. 40 participants, will be randomised to receive ten sessions of either active or sham tDCS over a 2-week period. Proof of concept will be measured by protocol compliance, attrition, and tolerance. Tinnitus loudness, symptom severity, and other relevant outcomes will be measured using self-report measures and electroencephalography.

Conclusions The study’s primary aims are to assess the tolerability of multiple tDCS treatments in tinnitus patients by way of treatment adherence and satisfaction, devise an evidence-based protocol and derive a minimum sample size for a future controlled efficacy trial. Secondary aims are to compare different subjective measures of tinnitus, as well as electrophysiological measures of underlying brain activity and to explore the feasibility of individualised head and current flow modelling for the development of future individualised treatment regimens using structural magnetic resonance imaging data acquired in a subset of our patients. The results will yield new insights into tinnitus mechanism and treatment-related changes. Trial Registration: This study is registered at ClinicalTrials.gov (NCTNCT06628414).