Contraindications of rTMS: Why a Prior Evaluation Is Essential
Implants, devices, seizures, and other conditions need to be reviewed before starting rTMS.
Repetitive transcranial magnetic stimulation (rTMS) is applied from outside the body and requires no surgery. Even so, it is not suitable for everyone. The magnetic field, the frequency of the pulses, and each person's clinical condition make a careful prior evaluation necessary.
Implants and Metal Objects
The presence of certain metal objects or electronic devices near the stimulation area can be a contraindication. Examples that must be reported include cochlear implants, intracranial clips, brain stimulators, electrodes, metal fragments, and certain medical devices.
The risk depends on the material, location, and characteristics of the device. Simply saying "I have an implant" isn't enough — it's best to bring any available documentation so the team can properly evaluate it.
Dental work is treated differently, but it should still be mentioned. The decision rests with the clinician and the safety criteria of the equipment being used.
History of Seizures
rTMS can alter brain excitability. A history of seizures or epilepsy calls for a specific evaluation. The risk and the approach taken depend on how well the condition is controlled, medications, the type of protocol, and other factors.
Not every history of seizures automatically leads to the same decision. Complete information allows the case to be properly assessed.
Medical and Psychiatric Conditions
A manic episode, active psychosis, or other situations of instability may require stabilization or a different approach. Head injuries, complex neurological conditions, migraines, cardiac disorders, and hearing difficulties are also reviewed.
Pregnancy, age, and other special circumstances call for an individualized conversation. The evidence and recommendations can vary depending on the protocol and the indication.
Medications and Substances
The care team needs to know about all medications, supplements, and substances the person uses. Some can affect the seizure threshold or the clinical response.
A treatment should never be stopped or changed on one's own before a session. The clinician will indicate how to proceed.
What a Responsible Evaluation Includes
Preparation may include:
- medical and psychiatric history;
- neurological history;
- a list of medications and substances;
- an inventory of implants and devices;
- review of prior studies;
- discussion of risks and benefits;
- informed consent.
There should also be a clear channel for reporting any changes that occur during treatment.
Safety Starts With Information
Hiding a piece of medical history out of fear of being turned away from treatment increases the risk. An evaluation isn't meant to automatically rule someone out, but to decide whether rTMS is appropriate and under what conditions.
Chapter 10 of "New Hope for Treatment-Resistant Depression Without Medication" organizes the contraindications and precautions worth knowing before a consultation.
