The appraisal of tinnitus severity and the effect of transcranial direct current stimulation

Date: 4 July 2016

Venue: Antwerp University Hospital (UZA) - Auditorium Kinsbergen (route 12) - Wilrijkstraat 10 - 2650 EDEGEM

Time: 6:00 PM

Organization / co-organization: Faculty of Medicine and Health Sciences

PhD candidate: Sarah Rabau

Principal investigator: Prof P. Van de Heyning & Prof V. Van Rompaey

Short description: PhD defence Sarah Rabau - Faculty of Medicine and Health Sciences


The pathophysiology behind tinnitus is still not clear and the character of it is very heterogeneous. The goal of the dissertation was twofold, namely to get insight in the tinnitus outcome measures and to investigate the neuromodulation technique tDCS as a possible therapy for tinnitus.

When a patient visits the ENT department it is important to assess all the aspects of tinnitus and its comorbidities. Several outcome measures are used in the literature and to increase the effect size in studies, it is important to choose the right outcome measure for being evaluated. When assessing the effect of tinnitus on daily life the dissertation suggests using self-reported questionnaires. Further research should demonstrate which questionnaires are most suitable for measuring treatment-related changes. The need for a consensus hereabout is very high in order to make it possible to compare study results across different research centers. Psychoacoustic measures can be used in research when trying to influence the loudness or the frequency, but not the burden experienced by the patient, which is of interest in a clinical situation. The role of Event-related potentials (ERP) as a possible objective outcome measure was also assessed. The amplitude of the ERP components might be an objective measure of tinnitus loudness.

The second goal of the dissertation was to evaluate tDCS as a possible treatment option for tinnitus. The inter-subject variability was great and the observed benefit for the patient was rather limited. Although no clear effect of cathode placing and timing could be demonstrated, an ERP study showed that tDCS is able to influence brain structures. Further research should always include a sham group and parameters such as electrode positioning, current orientation and intensity should be further investigated, as well as the effect of other neuromodulation forms.