TRANSCRANIAL MAGNETIC STIMULATION (TMS)
There is new hope for people who suffer with depression—Transcranial Magnetic Stimulation (TMS). It is especially helpful with treatment-resistant depression, for those who do not respond to antidepressants, as well as people who wish to avoid the side effects frequently caused by medication. TMS treatment usually includes four to six weeks of non-invasive, in-office treatments that take less than an hour each day, five days each week.
What is TMS?
TMS is a treatment that safely delivers magnetic pulses to areas of the brain that are responsible for mood. Instead of using invasive electrical currents like in electroconvulsive therapy (ECT), the magnetic pulses from TMS are similar in strength to those emitted during a typical MRI. The pulses are directed toward the prefrontal cortex of the brain to change the magnetic field and stimulate neurons within the mood center. This not only mitigates depression for a short time but can also result in long lasting relief.
Benefits of TMS
- Non-invasive—no anesthesia, electrodes or electrical current used
- Simple, in-office—administered by a technician and the patient can drive home afterward
- For treatment-resistant depression—those not helped by antidepressants can benefit
- No drug side effects—no reported nausea, weight gain, dry mouth or decreased sex drive
- Long-lasting—after initial 4-6 weeks, maintenance may or may not be needed later
How does TMS work?
TMS treatment is performed in a doctor’s office, while the patient is fully awake and seated in a comfortable chair. Because the magnetic pulses make a sound similar to that of a woodpecker, earplugs are provided. The TMS device is then placed in the proper position on the head and the magnetic pulses are delivered. The process usually takes between 20 and 40 minutes.
It is relatively simple.
- Patient takes a seat
- Device is placed on the head
- Pulses are delivered for a short time
- Patient returns to daily activities
Conditions treated by TMS
In the United States, the FDA approved TMS in 2008 as a treatment to alleviate the symptoms of treatment-resistant depression. It has also been approved for depression in Canada, Australia, New Zealand, Europe, and Israel. In addition, it has been CE approved in Europe for the treatment of bipolar disorder, PTSD, chronic pain, OCD, and adult AD/HD.
Advantages over other treatments.
In the past, the most common treatments for depression have been medication and/or psychotherapy. With TMS, psychotherapy is still encouraged because it can help people maintain mental health. However, unlike antidepressants, TMS has few if any side effects.
Reported side effects of antidepressants include:
- Weight gain
- Fatigue or drowsiness
- Dry mouth
- Decreased sexual desire or function
Side effects of TMS
Some patients report slight headaches or some discomfort at the treatment site just during the actual treatment. About a third of patients notice a prickly, tingly sensation on their scalp while the stimulating pulses are being administered. One in 1,000 patients experience a mild seizure; however, it should be noted that this risk is approximately the same as that cause by some antidepressants. In addition, the seizures related to TMS typically end when the magnetic stimulation is stopped.
Exceptions to TMS treatment
People who have metal implanted in or near their head should not have TMS. Exceptions include those with dental fillings, crowns and/or braces. Metals that prevent TMS treatment include:
- Pacemakers or implanted defibrillators
- Any stents from the neck up
- Aneurysm clips
- Metallic implants in ears or eyes
- Ammo fragments near the head
- Facial tattoos with metallic ink
- Any metal near the head that cannot be removed
TMS and insurance
As TMS is being used by more physicians and patients with notable positive results, more and more insurance companies now cover or partially cover the treatment. Major insurance companies in the United States that now cover TMS include Anthem Blue Cross Blue Shield and MHN (HealthNet). There are several other state and national companies that provide reimbursement when TMS is deemed appropriate. Your local TMS treatment provider can help you determine eligibility and many will submit the paperwork for you.
The history of TMS
The idea of bioelectricity dates back to the late 1700s when Luigi Galvani and Alessandro Volta made differing yet similar discoveries regarding electricity and muscle contraction. Another important contribution came in 1831 when Michael Faraday discovered electromagnetic induction. The first study with TMS was performed by Anthony Barker and his colleagues who used electromagnets for the conduction (transmission of excitation) of nerve impulses. Direct electric current had been used previously, such as with ECT, but the magnetic stimulation greatly reduced the discomfort involved.
In 2008, TMS was approved by the FDA for use with treatment-resistant depression. It is currently being researched and used to help with a range of disorders and diseases such as anxiety, OCD, ADHD, schizophrenia, PTSD, substance abuse, addiction, tinnitus, multiple sclerosis, ALS, motor disability after stroke, Alzheimer’s and Parkinson’s.
The science behind TMS
The process of TMS treatment involves taking an enclosed coil that produces a magnetic field and placing it against the scalp. Capacitors from the TMS machine pass electrical currents through the coils that create brief, pulsating magnetic fields that pass through the skull and create electric currents in the neurons or nerve cells of the brain. The electric field changes the current of the neurons and the firing potential. This has a sort of ripple effect, as the firing of certain neurons then triggers the firing of adjacent neurons. In this way, TMS treatment accesses the area of the brain implicated in mood regulation, specifically the prefrontal cortex.
Research supporting TMS
In a study of 301 participants who had treatment-resistant depression, nearly half of them showed complete or partial improvement in symptoms. In addition, only 13% of those who had improvement noticed relapse of depression after six months. Also, when people started to show early signs of recurrence in depression over time, TMS was reintroduced and relapse was prevented in 85% of the cases. (Biol Psychiatry. 2007 Dec 1;62(11):1208-16. Epub 2007 Jun 14.)
Types of TMS Machines
Currently there are two different types of TMS machines made by two different companies. One is called NeuroStar and the other is Brainsway. Both have proven to be effective in the treatment of depression. To date, there have been no direct comparisons that show which machine might be more effective.
- Plastic covered coiled placed on skull
- No cooling system required
- Provides more focal or localized pulses
- Pulses delivered 1.5 cm below the skull
- Treatment time: 37 minutes
- Total treatment time: 4-6 weeks
- Helmet with coils placed over skull cap
- An in-helmet cooling system used for coils
- Deeper, wider dispersion of pulses
- Pulses delivered up to 8 cm in depth
- Treatment time: 20 minutes
- Total treatment time: 4-6 weeks