What Is Transcranial Magnetic Stimulation and How Does It Help Depression?
As a psychiatrist, I have been treating patients for well over 10 years.
For the past three years I’ve included transcranial magnetic stimulation (TMS) therapy in my checklist of potential treatments after discovering how beneficial it can be in treating debilitating depression.
Now, I use the term “debilitating” very intentionally because the symptoms of clinical depression are causing intense distress and dysfunction for the person more days than not.
I have taken care of people of all ages, backgrounds and stages of life, but the common thread among all of them is the extreme hopelessness they feel, the dark hole they all feel to be in with no way out.
Until relatively recent years, medications, talk therapy and electroconvulsive therapy (ECT) were the only readily available treatment options for depression. It was very difficult for us in the behavioral health world to “think outside the box.”
Once researchers began to conceptualize the brain in another way, we opened up the opportunity for technology to meet mental health.
Electricity Powers Your Brain
The brain has long been considered a great conductor of electricity.
Researchers in the field of psychiatry hypothesized an electromagnetic field can be used to create an action potential and thereby depolarize neurons. This in turn would send cascading signals throughout an entire circuit of neurons, triggering the secretion and modulation of various neurotransmitters within that circuit.
In other words, could magnetic pulses (of which we are already familiar with this technology in MRI) targeted at the brain be converted to electrochemical energy and in turn, do what systemic medications have been trying to do to improve symptoms, but in a localized, focused treatment?
The answer is yes.
This treatment is called transcranial magnetic stimulation or TMS.
In addition, taking advantage of the concept that the brain learns with repetition, electrical pulses would need to be repeated over time, hence repetitive transcranial magnetic stimulation, or rTMS.
How Does TMS Work?
TMS uses an MRI-strength magnet targeted at the frontal portion of the patient’s head and uses a series of repeated pulses totaling 3,000 pulses per treatment session.
It then triggers a specific area of the brain called the dorsolateral prefrontal cortex (DLPFC) to modulate various neurotransmitters based on the mental health condition the patient is experiencing. This particular area is linked electrochemically to deeper brain structures, such as the amygdala, hippocampus and striatum, and this in turn translates to stimulation of all structures in the circuit.
You stimulate one, you stimulate them all, the domino effect!
With repeated TMS treatments, the brain then remembers these signals and is able to regulate the neurotransmitters autonomously. With proper regulation of the involved neurotransmitters, the patient can experience significant symptom relief, allowing them to live their lives without the daily struggle.
How Does TMS Help With depression?
In 2008, the FDA officially approved the use of repetitive transcranial magnetic stimulation therapy for “treatment-resistant” or refractory depression.
People struggling with refractory depression find it very difficult to get any symptom relief with traditional mental health interventions, such as antidepressants and psychotherapy.
Typically, patients with refractory depression have tried many antidepressant medications to no avail. They either cannot tolerate the medications due to side effects and have to discontinue the medication and try another, or they simply do not see any results on adequate and therapeutic dosing.
Patients end up trying various medications over the course of many years, but during this time the patient has not yet had much symptom relief. TMS may be another method patients can try.
A TMS course of treatment consists of:
- 30 consecutive treatment sessions
- Last six sessions tapered over three weeks
- Sessions lasting 18 minutes and 45 seconds
How Effective is TMS Therapy?
Studies suggest one course of TMS can provide symptom relief for nearly 60% of patients and benefits from TMS can be maintained at least 12 months post-treatment course. Everyone is different in terms of when the patient begins to feel the positive changes from treatment.
Very often, the people in the patient’s life on a regular basis, such as a spouse, close friend or coworker, will notice the changes before the patient themselves will notice. This is because it can be a gradual change and it should not feel like a magical force that suddenly puts a smile on the face.
TMS treatments should lift the symptoms of depression that don’t belong to the patient so that the patient can simply be and feel like themselves.
When can you expect to feel relief with TMS?
- A third of patients may see a change in the first third of the treatment course
- A third of patients might see improvement in the middle third
- A third of patients may note benefits in the final third portion of the course
Also, patients can continue to see symptom improvement even three to four weeks after TMS treatment ends. This is why it is important to complete the course so that the optimum benefits can be maximized and achieved.
What Are the Results of TMS?
Exact numbers vary, but clinical studies suggest approximately 60-65% of patients who undergo TMS will positively respond, which means obtain at least a 50% improvement in their depression symptoms, and 30-45% of patients can achieve full remission with one TMS course.
The success rates of TMS are even higher when paired with psychotherapy.
What Are the Benefits and Risks of TMS?
There is a limited range of approved-brand TMS devices available, and TMS providers vary regarding which system is utilized in individual practices. Most devices include a focused magnetic beam emitting pulses, but they differ in the engineering of the equipment from system to system.
A physician who offers TMS therapy should be certified to treat patients using that specific TMS system and should be the provider who conducts the initial brain mapping for each patient. A “mapping” is when the physician uses the magnetic pulses to locate the motor strip on the individual’s brain, which then guides the provider where to target the beam during treatment.
Brain mapping and the subsequent TMS treatments can be performed in an outpatient office setting, with the patient fully awake and able to drive home immediately following every treatment session, as there is no anesthesia. This is one great benefit to TMS, in that it allows the patient to maintain their independence during the treatment course.
Potential TMS Side Effects
TMS treatments are virtually painless, only possibly causing some scalp tenderness while the pulses are emitted. It is not known for causing lasting headaches, however for patients prone to headaches, the doctor may recommend premedicating with an over-the-counter pain reliever.
TMS treatments do not cause any memory deficits. In fact, some patients feel that their cognition improves with TMS. Some patients in the beginning of a treatment course do report a sleepy or “lulling” feeling several hours after. There is a small risk of seizure with TMS therapy in the general population.
Other than having metal or ferromagnetic material embedded in the brain such as shrapnel, aneurysm clips or a deep brain stimulator, there are no absolute contraindications to treatment. Even patients with various models of pacemakers can potentially receive TMS.
TMS can potentially positively impact the lives of millions of people. However, major depressive disorder (clinical depression) is not the only psychiatric condition that can be improved by TMS, though TMS isn’t yet approved by the Food and Drug Administration (FDA) for all conditions.
There are many promising reports that have emerged in peer-reviewed journals shedding light on other applications for TMS therapy, especially anxiety. In September 2018, the FDA approved TMS for treating obsessive-compulsive disorder (OCD). It is also being investigated for other conditions like generalized anxiety disorder and post-traumatic stress disorder (PTSD).
When treatment is available but has not yet been officially approved by the FDA, we refer to that treatment as “off label.” At our TMS treatment centers, the treatment arsenal includes protocols that are still in the investigatory phases as far as efficacy, but safety has been established.
As we learn more and more about the concept of neuroplasticity and the interplay with magnetic field technology, we have a broader range of conditions TMS may safely and effectively treat.
In addition to depression and various anxiety disorders, experimental protocols exist to treat conditions such as fibromyalgia, neuropathic pain, facial pain, addiction, ADHD, and cognitive difficulties related to dementia and migraine.
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