Would You Consider Deep Transcranial Magnetic Stimulation?

July 24, 2014

In January of 2013, the FDA cleared the first Deep Transcranial Magnetic Stimulation (TMS) system for treatment-resistant major depression. In standard TMS (which was FDA-cleared in 2008), direct neuronal activation is limited to a depth of about 1.5 cm in cortical regions, with activation of deeper structures resulting from secondary processes. With Deep TMS, the different design of the coil system allows for greater penetration and direct neuronal activation up to a depth of 6 cm, permitting direct excitation or inhibition of deeper brain structures. 

A study based on an FDA-approved clinical trial protocol was conducted involving 233 patients at 14 sites in the United States, four in Israel, two in Germany, and one in Canada. Study participants were diagnosed with major depression and had previously failed to respond to or adequately tolerate antidepressant medications. Results showed that 36.7% of patients in the treatment group achieved a significant response (greater than a 50% reduction in their score on the Hamilton Depression Rating Scale-21) compared to 20.5% in the control group (P=.0148). In addition, 30.4% of patients in the treatment group achieved remission (Hamilton Depression Rating Scale-21 score of less than 10) compared to 14.5% of the control group (P=.0148).

Among the various trials that have been conducted using this technology, the most commonly seen side effects have been transient headache and scalp discomfort. There have been a few reports of insomnia and dizziness, as well as three occurrences of generalized seizure during the treatments.

While Deep TMS is currently FDA-cleared in the United States only for treatment-resistant major depression, the treatment has been approved in the European Union for a variety of conditions including cannabis addiction, cocaine addiction, Alzheimer’s disease, autism, bipolar disorder, blepharospasm, depression, obesity, Parkinson’s disease,  posttraumatic stress disorder, schizophrenia, stroke rehabilitation, Tourette’s syndrome, and chronic neuropathic pain.

There are no clear-cut methods for determining which of these brain stimulation techniques might be most appropriate for every patient. Factors to consider in making the decision would include convenience and local access to the technology, insurance coverage, medical comorbidities of the patient, and level of experience of the person providing the treatment. ECT has been in use the longest so we therefore have the greatest level of history and experience with this treatment. However, it can carry with it some degree of risk of memory impairment and it is the most invasive of all of the listed treatments.

TMS is a newer treatment that is less invasive, but not as routinely covered by insurance or as readily available in all locations. It is largely free of systemic side effects but does require treatments five days per week for 4 to 6 weeks and may in some ways be less convenient than ECT. Deep TMS is the newest procedure with the least amount of clinical data, though the early data does appear compelling in terms of the variety of types of symptoms that reportedly can respond to this form of treatment.

If available in your area, would you consider the use of Deep TMS? How would you decide between the options of TMS, Deep TMS, and ECT? 

Chris Bojrab, MD, is the president of Indiana Health Group, the largest multidisciplinary behavioral health private practice in Indiana, established in 1987. He is a board certified psychiatrist and a Distinguished Fellow of the American Psychiatric Association who treats child, adolescent, adult, and geriatric patients. His areas of interest include psychopharmacology, sleep disorders, and gambling addiction. For more information and disclosures, visit  www.chrisbojrabmd.com

The views expressed on this blog are solely those of the blog post author and do not necessarily reflect the views of Psych Congress Network or other Psych Congress Network authors.