Information About Transcranial Magnetic Stimulation
Transcranial Magnetic Stimulation (TMS) is a non-invasive procedure that involves a pulsating magnetic field used to stimulate targeted areas of the brain. TMS uses an electromagnetic coil that rests on an individual’s head, and an alternating electric current is passed through the coil. The flow of current causes the coil to emit a pulsating magnetic field, which stimulates the area of brain tissue directly underneath the coil. The induced electric field can cause the firing of neurons within the area of stimulation and activate certain neural circuits involved in emotion. With the ability to accurately target selected areas, TMS can be focused on areas of the brain that are associated with depression and/or other mood disorders. For some people, it has been shown to help treat symptoms of mood disorders.
For additional reading, please refer to: POST Repetitive Transcranial Magnetic Stimulation In Depression: A Changing Landscape Article.
How it Works
Currently, it is not understood fully how TMS relieves symptoms of mood disorders. It is thought to work by stimulating neurons in targeted areas of the brain, and specific neural circuits involved in mood regulation. Repeated TMS treatment seems to improve how these brain areas and circuits operate, to help with depressive symptoms in some people. To completely understand TMS’s effect on the brain and how we can increase its efficiency is another reason why more research is needed in this area.
TMS was approved by Health Canada to treat depression in 2002. However, some evidence shows that TMS may also be effective in treating schizophrenia, anxiety, pain disorders, as well as many other related disorders. More research studies investigating TMS can determine which procedure works best, whether there are any unknown long-term effects, and how effective TMS is at treating different disorders. These research studies can increase the use of TMS as a regular treatment therapy.
Why is it Needed?
Psychiatric disorders (such as depression and schizophrenia) are very complex disorders, and sometimes treatments such as medication and talk therapy are not successful for everyone. TMS can be a suitable, safe option for those who do not respond to other treatments.
TMS is a non-invasive procedure, and does not require: surgery, induction of seizures, or any form of an anesthesia. TMS has not been shown to be associated with memory loss.
Common Side Effects – Common side effects are mild and usually end within the first few sessions of treatment. Side effects may include: headaches, tenderness at site of stimulation, and twitching of facial muscles.
Uncommon Side Effects – More serious, but rare side effects are seizures. The occurrence of seizures is less than 1/1000.
TMS DEPRESSION STUDY
Major Depressive Disorder (MDD) is a very common medical condition. There are many causes and influences, such as: life experiences, genetics, and changes in the way the body and brain function. MDD is often treated with antidepressant medication, however, many patients do not respond to medication treatment. Treatment resistant depression affects about 30-40% of patients and over the past decade; repetitive transcranial magnetic stimulation (rTMS) has been shown to be an effective and a well tolerated alternative approach for those dealing with treatment resistant depression.
In this study, we will be gathering detailed information regarding: your psychiatric history, depression symptoms, range of personality / cognitive capabilities, as well as lifestyle factors. An MRI scan and electroencephalography (EEG) scan will be given before and after rTMS treatment to determine changes in brain activity. The rTMS treatment for depression will be administered every weekday for 4-6 weeks.
rTMS is a treatment that involves stimulating certain areas of the brain with magnetic field pulses. Over multiple rTMS sessions, the magnetic field pulses can gradually change the activity level of the stimulated brain region and help symptoms of depression. However, there is no consensus among clinicians as to which method should be used. This study will compare two different styles of stimulation to determine which is the best stimulation protocol to treat MDD.
The purpose of this study is to compare two different styles of stimulation in order to understand if they are equally effective in treating those with MDD. Participants will either undergo a standard stimulation or a newer stimulation named Theta Burst Stimulation. Overall, both styles use the same strength and target for each participant; they only differ in the duration of the stimulation. Since the approval by Health Canada in 2002, there has been a need to investigate whether newer protocols of rTMS can improve efficacy, decrease treatment time, and be made more convenient for patients. This is what this study would like to examine and provide insight towards.
The study is being conducted by several different researchers at University Hospitals located across Canada. The primary investigator in Vancouver is Dr. Fidel Vila-Rodriguez, director of the NINET lab at UBC Hospital.
- You are 18 to 59 years of age.
- You are experiencing a major depressive episode in Major Depressive Disorder.
- You failed to achieve a successful response to antidepressants.
- You are willing to undergo rTMS treatments and brain scans.
If considering, please inform us:
- If you are pregnant, or thinking of becoming pregnant
- All medications that you are taking, including herbal supplements and over the counter medication. If possible bring a list of medications, including how often you take them and the dosages.
- If you have had any past injuries or surgeries, or other physical or mental health problems. Including:
- Aneurysm clips or coils
- Stents in the neck or brain
- Implanted stimulators
- Cardiac pacemakers or implantable cardioverter defibrillator (ICD)
- Metallic implants in your ears and eyes, (ex: dental implants, cochlear implants)
- Hearing Aid
- 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
- History of seizures and/or family history of seizures
Common Questions Asked:
Q: Will my treatment/healthcare records be kept confidential?
A: Your confidentiality will be respected. No information or records that disclose your identity will be published without consent, nor will any of your information or records that disclose your identity be removed or released without your consent, unless required by law.
Q: How much will the treatment cost?
A: Nothing. TMS treatments can cost up to $250 per session, however, when participating in a research study, you will receive treatment for free.
Q: What is the benefit of participating in the study?
A: You may find that your symptoms improve, however this is not guaranteed. Information gathered from this study may help other people undergoing TMS for mood disorders in the future. In general, we hope that the information learnt from this study can be used in the future to benefit other people with depression and related disorders.
The treatments will take place every weekday for the duration of 4-6 weeks. Each day, you will have a session ranging from 10-45 minutes of rTMS treatment; the treatment length will depend on what treatment group you have been assigned to. If you respond well after 20 treatments, you may be eligible for an extension phase that would include an additional 10 treatment visits (2 additional weeks of treatment).
You will undergo an MRI scan and EEG session before starting rTMS treatment, and another MRI scan and EEG session when you are finished your rTMS treatments.
At the end of each week, there will be a monitoring visit to determine the state of your depression symptoms.
During Your Visit
Each treatment visit will take place at the Mood Disorders Centre at UBC Hospital.
- During your visit you will be escorted to the treatment room, where you will be seated in a comfortable chair. You will be asked to remove any magnetic-sensitive objects, such as: jewelry, earrings, credit cards, as they can become demagnetized due to the treatment. Next, you will be given earplugs, as the treatment can be loud for some people.
- While sitting, the TMS personnel will place a headband with a sensor on your head, and then will use a plastic pointer to map your head for the computer. This mapping allows for the computer to precisely locate the position of your head and then when combined with your MRI scan, locate the selected targets along your brain accurately.
- First, your motor cortex (movement area) will be located and stimulated. By applying stimulation to the motor cortex along the left side of your brain, the fingers of your right hand will respond. This process is known as the “motor-threshold”. It is done in order to determine the dose of stimulation that is individually suited for your treatment sessions.
- The TMS personnel will locate the targeted area for the study and begin the treatment. Once the TMS coil has been turned on, you will hear a repeating clicking noise for a few seconds followed by a pause. This sound will continue for the duration of the session.
About the Session
- The session will last either up to 10 or 45 minutes. The duration strictly depends on the group you have been assigned.
- The entire appointment will last 30 minutes to an hour.
- After the treatment, you may return to your regular activities. There is a possibility that you may feel some light-headedness and may want to schedule someone to pick you up from your appointment.
For more details regarding the study, or to discuss enrolment, please contact Christine Dobek at 604-827-1361.