Neural response during prefrontal theta burst stimulation: Interleaved TMS-fMRI of full iTBS protocols
Kai-Yen Chang,
Martin Tik,
Yuki Mizutani-Tiebel,
Anna-Lisa Schuler,
Paul Taylor,
Mattia Campana,
Ulrike Vogelmann,
Barbara Huber,
Esther Dechantsreiter,
Axel Thielscher,
Lucia Bulubas,
Frank Padberg,
Daniel Keeser
Affiliations
Kai-Yen Chang
Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany; Neuroimaging Core Unit Munich - NICUM, University Hospital, LMU Munich, Munich, Germany
Martin Tik
High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; Brain Stimulation Lab, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, USA; Corresponding authors at: Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany.
Yuki Mizutani-Tiebel
Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany; Neuroimaging Core Unit Munich - NICUM, University Hospital, LMU Munich, Munich, Germany
Anna-Lisa Schuler
Lise Meitner Research Group Cognition and Plasticity, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
Paul Taylor
Department of Psychology, LMU Munich, Munich, Germany
Mattia Campana
Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany; Neuroimaging Core Unit Munich - NICUM, University Hospital, LMU Munich, Munich, Germany
Ulrike Vogelmann
Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany
Barbara Huber
Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany
Esther Dechantsreiter
Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany
Axel Thielscher
Department of Health Technology, Technical University of Denmark, Kgs. Lyngby, Denmark; Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Amager and Hvidovre, Denmark
Lucia Bulubas
Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany; Neuroimaging Core Unit Munich - NICUM, University Hospital, LMU Munich, Munich, Germany
Frank Padberg
Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany; Neuroimaging Core Unit Munich - NICUM, University Hospital, LMU Munich, Munich, Germany
Daniel Keeser
Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany; Neuroimaging Core Unit Munich - NICUM, University Hospital, LMU Munich, Munich, Germany; Corresponding authors at: Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany.
Background: Left prefrontal intermittent theta-burst stimulation (iTBS) has emerged as a safe and effective transcranial magnetic stimulation (TMS) treatment protocol in depression. Though network effects after iTBS have been widely studied, the deeper mechanistic understanding of target engagement is still at its beginning. Here, we investigate the feasibility of a novel integrated TMS-fMRI setup and accelerated echo planar imaging protocol to directly observe the immediate effects of full iTBS treatment sessions. Objective/hypothesis: In our effort to explore interleaved iTBS-fMRI feasibility, we hypothesize that TMS will induce acute BOLD signal changes in both the stimulated area and interconnected neural regions. Methods: Concurrent TMS-fMRI with full sessions of neuronavigated iTBS (i.e. 600 pulses) of the left dorsolateral prefrontal cortex (DLPFC) was investigated in 18 healthy participants. In addition, we conducted four TMS-fMRI sessions in a single patient on long-term maintenance iTBS for bipolar depression to test the transfer to clinical cases. Results: Concurrent TMS-fMRI was feasible for iTBS sequences with 600 pulses. During interleaved iTBS-fMRI, an increase of the BOLD signal was observed in a network including bilateral DLPFC regions. In the clinical case, a reduced BOLD response was found in the left DLPFC and the subgenual anterior cingulate cortex, with high variability across individual sessions. Conclusions: Full iTBS sessions as applied for the treatment of depressive disorders can be established in the interleaved iTBS-fMRI paradigm. In the future, this experimental approach could be valuable in clinical samples, for demonstrating target engagement by iTBS protocols and investigating their mechanisms of therapeutic action.
