Should transcranial magnetic stimulation research in children be considered minimal risk?

Objective: Transcranial magnetic stimulation (TMS) is a neurophysiologic technique with research applications. Institutional Review Boards (IRBs) must carefully consider potential risks and possible benefits in research involving children. The purpose of this study is to provide concise information for investigators and IRBs about the safety of single and paired pulse TMS research in children. Methods: This paper has 4 sections: (I) Regulations governing research in children are reviewed and applied to the use of TMS. (II) Energy imparted by TMS is assessed in terms of theoretical biological risks to human subjects. (III) Through MEDLINE review, the empirical evidence of risk from TMS is assessed. Reported adverse events, including issues related to risk of seizures and of hearing loss, are summarized. (IV) Safety data are presented from a study of TMS in children with Tourette Syndrome. Results: No published or empirical evidence was found to suggest that single or paired pulse TMS is associated with more than minimal risk in children. Conclusions: IRBs may consider well-designed studies using single and paired pulse TMS protocols similar to those described in this study as bearing minimal risk to children. Significance: This manuscript may be useful as a reference to IRBs and TMS investigators.