STANDARD OPERATING PROCEDURE / Experimental Psychology
SOP No: 001-v.1
SOP Title: Use of TMS
SOP Number / SOP-EP-001-v.1
SOP Title / Use of Transcranial Magnetic Stimulation (TMS)
NAME / TITLE / SIGNATURE / DATE
Author
/ Riikka Mottonen / MRC Career Development Fellow, Department of Experimental Psychology / 15/02/2012
Reviewer / Kate Watkins / University Lecturer, Department of Experimental Psychology
Authoriser
Effective Date: / 01/10/12
Review Date: / 30/09/13

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STANDARD OPERATING PROCEDURE / Experimental Psychology
SOP No: 001-v.1
SOP Title: Use of TMS

1.  purpose

Transcranial Magnetic Stimulation (TMS) involves potential risks to the subjects. The purpose of this Standard Operating Procedure (SOP) is to ensure the correct and safe use of this brain stimulation method, which minimizes the potential risks.

2.  introduction

TMS is a technique that allows stimulation of the brain of a subject by rapid switching of a magnetic field in a coil placed over the head. A few cases of accidental TMS-induced seizures have been reported, mostly prior to the definition of safety limits (Wasserman, 1998; Rossi et al., 2009). The seizures were brief, limited and did not generalize. The risk of the technique can be minimized by reducing the stimulation intensity, the duration of a train of stimulation and the interval between trains, and by adequate screening of the subjects. Subjects may experience some discomfort during TMS. In susceptible individuals, TMS may cause headache.

3.  Scope

The SOP relates to all experiments that use TMS in the Department of Experimental Psychology, at the FMRIB centre and in related University of Oxford laboratories at the John Radcliffe and Warneford hospitals where researchers have agreed to follow the procedures described here. Researchers are required to follow these procedures if they are seeking ethical approval via the Central University Research Ethics Committee using the TMS approved protocol (MSD/IDREC/2013/P21.1).

4.  Definitions

4.1  TMS

Transcranial Magnetic Stimulation

4.2  Experienced Researcher

An experienced researcher is defined here as the Principal Investigator (PI) or person delegated this responsibility by the PI. It is expected that an experienced researcher would be a graduate who has had supervised experience of TMS research for a minimum of 10 sessions, had attended safety training and basic life support training in the past two years. This person should be aware of the potential side effects of TMS and procedures for monitoring and reporting of adverse events. They should also be able to answer any questions concerning the safety of TMS.

5.  responsibilities

5.1  TMS Operator

An experienced researcher responsible for the safe use of TMS.

6.  SPECIFIC PROCEDURE

6.1  Screening of the Subjects

The subjects should fill in and sign a safety screening form (appended) before each TMS session. An answer of ‘yes’ to any question on the screening form does not automatically mean that it is unsafe for the subject to participate in a TMS experiment, however it will mean that further questions will need to be asked of the subject. The TMS Operator will write on the screening form a summary of the answers to additional questions that they have asked that indicate why it is safe for the subject to participate in the experiment. If there are any concerns as to whether it is safe for the subject to participate in the experiment, the TMS Operator should seek advice. If there is any uncertainty concerning safety, the subject should not participate in the experiment.

6.2  Delivering of TMS

Two researchers (TMS Operator and assistant) should be present (in the same room) during stimulation. The TMS Operator must be an experienced researcher as defined above (4.2). The assistant can also deliver TMS to the subject under the guidance of the TMS Operator. Delivering TMS does not involve any risks to the researchers. However, researchers who are pregnant should not deliver TMS (i.e., hold the coil).

The maximum intensity, length and frequency of the pulse trains should be stated clearly within the experimental protocol that has been given ethical approval, and these parameters should not be exceeded at any point of the experiment.

During TMS, earplugs should be used to protect subjects’ hearing.

Before TMS, subjects should be warned about unusual sensations (e.g., muscles twitches, eye blinking, tapping under the coil). If the subject reports experiencing pain or there are any safety concerns, the stimulation should be terminated immediately.

If TMS induces a seizure, the emergency services should be contacted immediately (tel. 2222 on a hospital phone or telephone 999 if a hospital phone is unavailable).

6.3  Reporting adverse events

Adverse events, such as a suspected seizure should be reported in the first instance to departmental safety officers in accordance with departmental policy. They must also be reported to the Research Ethics Committee who gave approval for the study. Details of the event and the stimulation parameters can also be shared with the international community via the journal Brain Stimulation and is recommended by the most recent safety guideline (Rossi et al., 2009).

7.  forms/Templates to be used

TMS Safety Screening Form

8.  internal and external references

8.1  External References

Rossi S, Hallett M, Rossini PM, Pascual-Leone A and The Safety of TMS Consensus Group (2009) Safety, ethical considerations, and application guidelines for the use of transcranial magnetic stimulation in clinical practice and research. Clinical Neurophysiology 120, 2008–2039.

Wassermann, EM (1998) Risk and safety of repetitive transcranial magnetic stimulation: Report and suggested guidelines from the International Workshop on the Safety of Repetitive Transcranial Magnetic Stimulation Neurophysiology, 108(1), 1–16.

Brain Stimulation website: http://www.brainstimjrnl.com

9.  Change History

SOP no. / Effective
Date / Significant Changes / Previous
SOP no. /

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