How Does rTMS Work?
Repetitive Transcranial Magnetic Stimulation (rTMS) involves applies magnetic pulses that can induce electrical currents in focused areas within the brain. The frequency (how fast or slow) of pulses activate or inhibit brain cells. High frequency rTMS in prefrontal brain regions stimulate neurons involved in mood regulation. rTMS may modify brain circuits, neuron growth factors (BDNF), neurotransmitters (serotonin, dopamine), and increase brain-derived (endogenous) opioids.
What Is rTMS Used for?
rTMS was initially a tool for neuroscience investigation of the brain. It has subsequently been studied and FDA approved for depression at this time. It is under investigation for other neuropsychiatric and pain disorders, but not FDA approved. Some insurers do cover rTMS for the treatment of unipolar depression, not other neuropsychiatric conditions. Antidepressant medications and psychotherapy are the first line treatments for major depression, but don’t work for a third of patients. rTMS is used as next-level treatment and may augment antidepressant medications or psychotherapy. Patients who have failed to achieve an adequate response from antidepressants, psychotherapy, or who are unable to tolerate medications, might consider rTMS therapy.
What Happens With an rTMS Procedure?
A patient sits in a treatment chair. Patients are asked to remove any magnetic-sensitive objects (such as jewelry) since rTMS uses magnetic pulses that can heat magnetic metals. Patients wear earplugs during treatment for hearing protection, as rTMS produces a loud clicking sound with each pulse.
During the first session, a motor threshold is found. This is the amount of machine energy needed to make the hand move when the coil is placed on the head in areas associated with movement. This measure tells the physician the patient’s rTMS treatment dose to stimulate neurons. The rTMS coil is properly positioned over the patient’s head for the motor threshold and subsequently repositioned into the treatment location. During the treatment, the patient hears a series of clicking sounds and feels a tapping sensation on their head under the treatment coil.
The treatment sensation can be initially uncomfortable. Thus we use lower doses for the first 3 sessions to help the patient accommodate to the treatment. Commonly the patient’s sensation modifies and while the stimulation is still felt, it is no longer uncomfortable.
Who Administers rTMS?
rTMS is always prescribed by a rTMS physician and then administered by a rTMS operator. A motor threshold is always determined by a rTMS physician. The treatment itself is administered by an experienced rTMS operator under the supervision of the rTMS physician or by the rTMS physician themselves.
The rTMS operator or physician will always be present to monitor the patient during the treatment. The patient can stop a treatment at any time by verbalizing this request to the rTMS operator.
How Long Is an rTMS Procedure?
It depends on the rTMS protocol and machine type. Some conventional, FDA-approved rTMS protocols can take upwards to an hour, but generally take about 30 minutes. Other protocols can be done in 20 minutes or less. The success of the treatment is dependent not on a single session but a series of sessions that are commonly done 5 days a week for 4 to 6 weeks followed by a 3 week taper. We commonly taper by giving 3 treatments in week 1 taper, 2 treatments in week 2 taper, and 1 treatment in week 3 taper.
Do I Need to be Hospitalized for a Course of rTMS?
No. Unlike ECT, rTMS does not require any sedation or general anesthesia, so patients are fully awake and aware during the treatment. There is no “recovery time”, so patients can drive home afterwards and return to their usual activities. This also means that rTMS is not offered during hospitalization either. Future research is needed to show that rTMS can be done effectively in an inpatient setting and reduce hospitalization duration, improve outcomes, and reduce rehospitalization rates before insurers will agree to pay for inpatient rTMS.
What Are the Side-Effects of rTMS?
There are few side effects associated with rTMS. Pain sensation at the site stimulation is common early in the rTMS series. This significantly decreases over the course of rTMS stimulation. Thereafter the most common side effect is headache, which is reported in nearly half of patients treated with rTMS. Headaches are mild and generally diminish over the course of the treatment. Over-the-counter pain medication, such as ibuprofen, can be used to treat these headaches.
The rTMS machine produces a loud noise. No evidence suggests there is hearing loss if earplugs are worn during the treatment.
rTMS is not associated with many of the side effects caused by medications, such as gastrointestinal upset, dry mouth, sexual dysfunction, weight gain, or sedation.
The most serious but rare risk of rTMS is seizures. However, the risk of a seizure is exceedingly low. We have never had a patient have a seizure from rTMS at MUSC Health.
What Would Make Me Ineligible for rTMS Therapy?
Patients with any type of non-removable metal in their heads (not including braces or dental fillings) should not receive rTMS. rTMS in those situations could cause objects to heat up, malfunction, and result in serious injury or death. Below is a list of metal implants that can prevent a patient from receiving rTMS:
- Aneurysm clips or coils
- Stents in the neck or brain
- Implanted stimulators
- Electrodes to monitor brain activity
- Metallic implants in your ears and eyes
- Shrapnel or bullet fragments in or near the head
- Facial tattoos with metallic or magnetic-sensitive ink
- Other metal devices or object implanted in or near the head
Please ask a rTMS physician if you would be excluded from rTMS based on one of these conditions above.
How Can I Get rTMS Treatment?
Before scheduling you for rTMS treatment, you must first be evaluated by one of our rTMS psychiatrists to determine if rTMS would be safe and appropriate for you. If you are requesting insurance to cover the rTMS therapy, then the clinic service will seek insurance authorization, which commonly takes days to weeks for confirmation.
Where Can I Get rTMS Treatment?
While there are other rTMS clinics in South Carolina, MUSC Health currently has 2 rTMS clinics in the Charleston area. One clinic is downtown at the Institute of Psychiatry, 67 President Street, near our research lab and ECT suite. The other clinic is in Mount Pleasant at 1280 Hospital Drive, Suite 200.