Transcranial Magnetic Stimulator (TMS) is a noninvasive procedure that uses magnetic fields to stimulate nerve cells in the brain to improve symptoms of depression. During TMS, a magnetic coil is placed near the skull and delivers electrical pulses to targeted areas of the brain.
How Does TMS Work?
TMS works by inducing small electrical currents in specific parts of the brain using powerful pulses from a magnetic coil placed near the skull. The magnetic field produced by the coil passes unimpeded through the scalp and skull and into the brain tissue below to modulate neuronal activity in brain regions associated with depression.
The magnetic pulses are brief—about one second in duration—and painless. Repeated sessions are needed for depression treatment, with each session lasting around 37 minutes. Current guidelines recommend up to 30-36 treatment sessions.
By targeting magnetic pulses to brain regions implicated in depression like the prefrontal cortex, Transcranial Magnetic Stimulator may help correct abnormalbrain activity and boost other areas that play a role in mood regulation. The precise mechanism is still uncertain but TMS appears to alter neuronal firing patterns and levels of neurotransmitters like serotonin and norepinephrine.
Background and Approval for Depression
TMS was approved by the U.S. Food and Drug Administration (FDA) in 2008 for treatment-resistant depression, which refers to depression that has not responded adequately to at least one antidepressant medication.
Prior to FDA approval, several randomized controlled trials demonstrated TMS to be generally well-tolerated and more effective than sham TMS treatment at reducing depression symptoms. Some studies also found short-term remission rates with TMS similar to electroconvulsive therapy (ECT) but without the cognitive side effects of ECT.
Longer-term follow up studies have also shown maintenance of antidepressant effects for up to 6-12 months in some individuals who later received maintenance TMS treatments. This provides hope TMS may help prevent relapses for at least some depression patients.
When Is TMS Used for Depression?
TMS is typically reserved for adults with major depression who have not responded sufficiently to at least one adequate trial of an antidepressant medication. It may be used in the following situations:
– Treatment-resistant depression – For patients who have not benefited from multiple medication trials.
– Intolerance to antidepressant side effects – For patients who cannot tolerate medications due to side effects.
– Pregnancy or breastfeeding – When antidepressants are not an option due to potential risks to mother or fetus/infant.
– Maintenance therapy – For sustaining antidepressant effects after an initial treatment course of TMS or ECT.
– Bipolar depression – Occasionally used as an add-on to medications when bipolar depression is very severe.
Identifying Candidates for TMS Therapy
Not all individuals with depression will benefit from TMS treatment. Careful evaluation by a psychiatrist is important to determine if a patient is a suitable candidate. Key considerations include:
– Diagnosis of major depressive disorder – TMS is FDA approved only for this condition.
– Treatment history – How many antidepressants have been trialed sequentially at maximum tolerable dose over adequate time period (6-8 weeks).
– Current symptoms – Severity and impact assessed using standard rating scales.
– Medical history – Other psychiatric or physical illnesses present that could impact response.
– Cognitive ability – Ability to provide consent and participate in daily TMS sessions.
– Lifestyle factors – Willingness and ability to commit to full treatment course, including repeat sessions.
Benefits and Risks of TMS Therapy
The primary benefit of TMS therapy is providing an additional non-drug option for treatment-resistant depression without medication side effects or risks of ECT like cognitive issues.
About half of patients receiving TMS in clinical studies experience a significant reduction in depression symptoms, often within 2-3 weeks of starting treatments. Complete remission is seen in roughly 30% of cases. However, benefits may not persist without maintenance TMS in some individuals.
Risks are generally minor and include potential short-term headaches, scalp pain or discomfort during sessions. Seizures have occurred in rare instances in persons with a lowered seizure threshold. Standard safety precautions are followed during TMS administration to manage risks.
Longer-term safety data beyond 6-12 months of follow-up are still limited. Precautions are also usually needed if a patient has implanted metal devices or has had recent seizures, though most medical devices do not interfere with TMS.
Overall for TMS as a Depression Treatment
While, transcranial magnetic stimulator remains mostly a third-line option for treatment-resistant depression, clinical experience over the last decade suggests it provides a reasonably safe and effective option for many who have not benefited from other therapies. As research continues, the use of TMS may expand to early stages of depression treatment and potentially new psychiatric conditions in the future. Carefully conducted randomized trials are still needed to better establish optimal dosing strategies and long-term outcomes with TMS as a depression treatment modality.
*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
About Author - Vaagisha Singh
Vaagisha brings over three years of expertise as a content editor in the market research domain. Originally a creative writer, she discovered her passion for editing, combining her flair for writing with a meticulous eye for detail. Her ability to craft and refine compelling content makes her an invaluable asset in delivering polished and engaging write-ups. LinkedIn