Personalization of Repetitive Transcranial Magnetic Stimulation for the Treatment of Chronic Subjective Tinnitus

Abstract

Background: Personalization of repetitive transcranial magnetic stimulation (rTMS) for tinnitus might be capable to overcome the heterogeneity of treatment responses. The assessment of loudness changes after short rTMS protocols in test sessions has been proposed as a strategy to identify the best protocol for the daily treatment application. However, the therapeutic advantages of this approach are currently not clear. The present study was designed to further investigate the feasibility and clinical efficacy of personalized rTMS as compared to a standardized rTMS protocol used for tinnitus. Methods: RTMS personalization was conducted via test sessions and reliable, sham-superior responses respectively short-term reductions in tinnitus loudness following active rTMS protocols (1, 10, 20 Hz, each 200 pulses) applied over the left and right temporal cortex. Twenty pulses at a frequency of 0.1 Hz served as a control condition (sham). In case of a response, patients were randomly allocated to ten treatment sessions of either personalized rTMS (2000 pulses with the site and frequency producing the most pronounced loudness reduction during test sessions) or standard rTMS (1 Hz, 2000 pulses left temporal cortex). Those participants who did not show a response during the test sessions received the standard protocol as well. Results: The study was terminated prematurely after 22 patients (instead of 50 planned) as the number of test session responders was much lower than expected (27% instead of 50%). Statistical evaluation of changes in metric tinnitus variables and treatment responses indicated only numerical, but not statistical superiority for personalized rTMS compared to standard treatment. Conclusions: The current stage of investigation does not allow for a clear conclusion about the therapeutic advantages of personalized rTMS for tinnitus based on test session responses. The feasibility of this approach is primarily limited by the low test session response rate.

Personalized Neuromodulation: A Novel Strategy for Improving Tinnitus Treatment

“…Various protocols involving stimulation frequency, stimulation position, and the laterality of brain stimulation were tested on two different days, effectively demonstrating the consistency of parameters required to achieve the best tinnitus suppression for each individual. These findings underscore the potential for developing individualized rTMS protocols [17][18][19].…”

“…Patients were then randomly assigned to either personalized rTMS (comprising 2000 pulses using the responsive protocol) or standard rTMS (1 Hz; 2000 pulses over the left temporal cortex). The personalized protocol had a greater effect than random stimulation [19]. An analogous method used a similar protocol, where frequencies of 1, 5, 10, and 20 Hz and continuous theta burst stimulation were consecutively administered to the left and right temporoparietal lobes and DLPFC during the experimental session.…”

Monitoring Changes in TMS-Evoked EEG and EMG Activity During 1 Hz rTMS of the Healthy Motor Cortex

“…Efforts in rTMS personalization for therapeutic use are already pursued and have the potential to account for certain factors of variability such as the individual intrinsic brain state (Chou et al, 2021;Cocchi and Zalesky, 2018;Klooster et al, 2021;Schoisswohl et al, 2022Schoisswohl et al, , 2021Schoisswohl et al, , 2020.…”

Activate & fire: a feasibility study in combining acoustic stimulation and continuous theta burst stimulation in chronic tinnitus

“…Data from study visits of both treatment groups were analyzed using linear mixed effect models separately for each assessment inventory (e.g., TFI). The model fitting followed the exact same procedure as already outlined in Schoisswohl et al, 2021Schoisswohl et al, & 2022. The following fixed effects as well as their interaction were tested in the model fitting procedure: time (screening, baseline, treatment end, follow-up), treatment group (activate & fire, 1 Hz rTMS).…”