Repetitive Transcranial Magnetic Stimulation (rTMS) is a procedure that stimulates the brain cells to take a control of your mood and depression. The repetitive magnetic pulses are responsible for causing changes in neuronal activity. As each magnetic pulse passes through the skull and into the brain, it induces a brief activity of brain cells underlying the treatment coil.
The frequency of pulse delivery influences whether brain activity is increased or decreased by a session of rTMS. Moreover, stimulation over the left and right sides of the brain can have opposite effects on mood regulation.
When is rTMS used?
Antidepressant medications and psychotherapy are the first line treatments for major depression. These treatments, however, do not work for all patients. In these instances, rTMS might be used as an alternative treatment, or to augment antidepressant medications or psychotherapy. Patients who have failed to achieve an adequate response from antidepressants, or who are unable to tolerate medications, might consider rTMS therapy.
What happens during an rTMS procedure?
Because rTMS uses magnetic pulses, before beginning a treatment, patients are asked to remove any magnetic-sensitive objects (such as jewellery, credit cards). Patients are required to wear earplugs during treatment for their comfort and hearing protection, as rTMS produces a loud clicking sound with each pulse, much like an MRI machine. Patients are seated during each session of rTMS.
During the first rTMS session, several measurements are made to ensure that the TMS coil will be properly positioned over the patient’s head. Once this is done, the TMS coil is suspended over the patient’s scalp. The TMS physician then measures the patient’s motor threshold, by administering several brief pulses. The motor threshold is the minimum amount of power necessary to make the patient’s thumb twitch and varies from individual to individual. Measuring the motor threshold helps the physician personalize the treatment settings and determine the amount of energy required to stimulate brain cells.
Once the motor threshold is determined, the coil is then brought forward so that it rests above the front region of the patient’s brain. During the treatment, the patients will hear a series of clicking sounds and will feel a tapping sensation under the treatment coil.
Motor threshold is not checked at every treatment but may be reassessed if the physician feels that it may have changed because of a change in medication.
Who administers rTMS?
rTMS is always prescribed by a TMS physician and the initial motor threshold is always determined by a TMS physician. The treatment itself is administered by an experienced TMS technician under the supervision of the TMS physician or by the TMS physician.The TMS technician or physician will always be present to monitor the patient during the treatment. The patient can stop a treatment at any time by asking the staff member to be present.
How long is an rTMS procedure?
rTMS therapy involves a series of treatment sessions. Treatment sessions vary in length depending on the TMS coil used and the number of pulses delivered but typically last around 30 – 40 minutes. Treatments are administered 5 days a week. A typical course of rTMS is 4 to 6 weeks. However, this can vary depending on an individual’s response to treatment.
Do I need to be hospitalised for a course of rTMS?
Unlike ECT, rTMS does not require any sedation or general anaesthesia, so patients are fully awake and aware during the treatment. There is no “recovery time”, so patients can drive home afterwards and return to their usual activities.
What are the side-effects of rTMS?
rTMS is well-tolerated by the patients. However, the most common side-effect that is experienced is a headache. This can be one of the reasons for the patients to discontinue the treatment.