Repetitive Transcranial Magnetic Stimulation (rTMS)
Overview
Transcranial Magnetic Stimulation (TMS) involves a series of short magnetic pulses directed to the brain to stimulate nerve cells. The magnetic pulses stimulate area neurons and change the functioning of the brain circuits involved.
Since 1985, research has been conducted with TMS to understand and treat a number of neurological conditions (i.e. migraine, Parkinson’s disease, tinnitus) and psychiatric conditions (i.e. depression and auditory hallucinations in individuals with schizophrenia). Most recently, researchers have been focusing on the use of repetitive TMS pulses (rTMS) as a treatment option for major depressive disorder, auditory hallucinations in schizophrenia, cognitive disorders, obsessive compulsive disorder and post-traumatic stress disorder.
How does it work?
Rapidly changing magnetic pulses cause neurons to change their firing pattern within the brain. By changing the firing pattern of neurons in brain circuits involved in a disorder such as depression, the dysfunctional brain patterns can change. The brain activity changes are thought to be a mechanism through which treatment occurs.
What is the Treatment like?
The patient remains awake during the procedure and can return to normal daily activities immediately following (no medication or anesthesia is required). The patient will be sitting comfortably in a recliner throughout the session. A treatment ranges between 5 minutes and 60 minutes. A typical treatment course is approximately 4-6 weeks.
What are the risks associated with TMS?
In a very small percentage (less than 1%) of people, rTMS can cause a self-limiting seizure. For this reason, those with a history of seizures (other than from ECT) cannot receive the treatment.
Side effects include involuntary eye blink or contraction of facial muscles (which are not painful and do not continue following the stimulation). Dizziness or light-headedness can occur after a treatment and it usually goes away quickly. Pain at the site of stimulation can occur as people adjust to the sensation of the treatment. Mild headache can occur in about one-quarter of people, but this usually goes away within 24 hours or with administration of acetaminophen (i.e. “Tylenol”).
Who can Receive TMS?
rTMS is currently offered in the context of ongoing research studies. We are conducting clinical trials for major depression and bipolar disorder. You must meet with a study coordinator in order to review the eligibility criteria in order to receive rTMS.
You must NOT:
- Have history of epilepsy or other seizure disorder
- Have any ferrous metallic implants in the skull
- Have a history of drug abuse within the past three to six months
- Have any unstable medical condition
- Be pregnant or attempting to becoming pregnant
Source: http://www.camh.ca/en/hospital/health_information/a_z_mental_health_and_addiction_information/rTMS/Pages/default.aspx