Transcranial Magnetic Stimulation (TMS)

The newly opened Transcranial Magnetic Stimulation (TMS) laboratory at Dell Children’s Medical Center provides advanced state-of-the-art brain mapping technology within a world-class laboratory and is poised to become a premiere site in Texas for functional neuroimaging.

What Is Transcranial Magnetic Stimulation or TMS?

TMS is a non-invasive (no shots or radiation) brain mapping technology that can identify the exact location of essential brain functions such as those involved in controlling the hands and feet or speech production. With this information, surgical procedures can be planned to remove diseased brain while minimizing damage to parts of the brain that are working correctly.

How Does TMS Work?

TMS uses a magnet precisely aimed at the brain to stimulate a specific brain region to determine what that region of the brain is used for. Using advanced methods, we can determine what brain functions occur in the region stimulated. The results are combined with the patient’s MRI to construct a “Functional Brain Map” to help physicians develop a treatment plan.

Who Would Benefit from TMS?

TMS can benefit many people who have chronic neurological problems or may need brain surgery.

  • Children with medically refractory epilepsy
  • Patients diagnosed with a brain tumor
  • Any patient who has consulted with a neurologist and neurosurgeon about brain surgery

How Long Does a TMS Scan Take?

The amount of time it takes to complete a TMS scan varies from person to person. However, patients should be prepared to be at Dell Children’s Medical Center for anywhere between 1-2 hours. During this time, there will be long stretches where the patient will be asked to remain still, but there will be opportunities for breaks. Patients needing sedation may involve additional time commitments.

How to Prepare for TMS

As an outpatient procedure, preparing for a TMS scan is minimal and often well tolerated by patients. The patient can eat normally before the scan and should take medications as usual, unless told otherwise.

Because TMS uses magnets to stimulate the brain, certain metallic or electronic implants may be affected. Please notify TMS department personnel in advance if the patient has an electronic implant, such as a pacemaker or a vagus nerve stimulator (VNS).

Other suggestions in preparing the patient for the TMS scan include:

  • Avoid caffeinated drinks (soda, coffee, tea) the morning of the test
  • The night prior to the test, wash the patient’s hair, but avoid hair products (no conditioner, oil, gel, mousse, or hairspray)
  • Glasses will be removed prior to the test; contact lenses are OK
  • A “blankie” or stuffed animal (without metal components) can be comforting for children

What to Expect during a TMS Procedure

When the patient arrives for the TMS procedure, they may have electrodes placed on their arms or legs if the physician has ordered it. The technician will then lead the patient into the room where the scan will take place, help them get into the chair and position their head properly for the procedure. They will be in a big chair that reclines back to make the patient more comfortable and position the him or her for the procedure. Once positioned, they will be asked to remain still. The TMS magnet makes a clicking sound each time the brain is stimulates and the patient may feel his or her hands or feet twitch. Once the procedure is done, the technician will come help them out of the chair.