In November 2021, Repetitive Transcranial Magnetic Stimulation therapy was added to the Medicare Benefits Schedule for eligible patients with diagnosed medication-resistant major depressive disorder.

The treatment is particularly useful for patients who don’t respond to drug therapies and are at risk of self-harm.

This was big and important news eclipsed by the COVID-19 rollout and anticipation of the country opening up again.

It was one of then health minister Greg Hunt’s important initiatives, and it was missed a little.

Effective but costly

Repetitive transcranial magnetic stimulation (rTMS) therapy, which uses magnetic fields to stimulate nerve cells in the brain to improve symptoms of long-term major depression, has been called “the new Prozac“.

But it was only available to people who could afford it. And because of a quirk in private insurance funding, patients were required to stay in hospital.

There was no clinical reason for them to stay in hospital as rTMS is an outpatient treatment.

But the insurers were billed for the cost of the hospital room, not the treatment.

For four weeks’ treatment, those private patients were paying between $3500 and $5000. One woman reportedly spent $12,000 on rTMS over two years.

This was all beyond the means of depressed patients who were struggling to hold down a job. The Medicare rebate purportedly opened up subsidised access to Transcranial Magnetic Stimulation (TMS) for these people.

‘A last resort’

Researchers and clinicians have described TMS as a “last resort” that has opened up a “a whole new field of psychiatry”.

As the ABC reported in a piece responding to the Medicare funding: “Figures have shown about 50 to 60 per cent of people with depression who have tried and failed to receive benefit from medications experience a clinically meaningful response with rTMS.

“Of those, about a third experience a full remission, meaning their symptoms go away completely.”

It’s not a cure-all by any means, but it was a legitimate game changer.

Yet it hasn’t provoked the same kind of media interest as that given to the sanctioned use of psychedelics for depression and PTSD.

Transcranial Magnetic Stimulation for treatment-resistant depression is subsidised by Medicare. Photo: Getty

The brain and depression

TMS was originally developed as a research tool to study the brain, how it works and how it goes wrong.

This research revealed that TMS could change the way brain structures behaved, opening the way for it to be used as a therapy.

This was compatible with the idea that different brain structures, when underperforming, might explain and ameliorate difficult conditions such as major depressive disorder (MDD).

MDD is characterised by persistent low mood, often accompanied by cognitive dysfunction, physical symptoms, and impaired social function. In its most severe phase, it leads to suicide.

A complex issue

As a 2018 review advised: “Numerous studies that focused on grey and white matter have found significant brain region alterations in major depressive disorder patients such as in the frontal lobe, hippocampus, temporal lobe, thalamus, striatum and amygdala.”

Although the results of these studies were “inconsistent” and “controversial”, the authors hypothesised that “there may be a ‘hub’ in MDD and that an impairment in these regions contributes to disease severity”.

According to previous reports, “significant circuits include the frontal‐subcortical circuit, the suicide circuit, and the reward circuit”.

When TMS is used in a clinical setting, the treatment tends to be applied to the frontal part of the cranium.

The Black Dog Institute led the first Australian randomised controlled trials of TMS to treat depression, commencing in 1997 under the leadership of psychiatrist Colleen Loo, Professor of Psychiatry at the University of New South Wales.

What happens during a TMS session?

One of the game-changing aspects of TMS is that it’s a “non-invasive” procedure. There is no surgery of cutting the skin.

Also, as the Mayo Clinic explains: “Unlike vagus nerve stimulation or deep brain stimulation, TMS does not require implanting electrodes.”

And, unlike electroconvulsive therapy, “TMS doesn’t cause seizures or memory loss”.

It also doesn’t require the use of anaesthesia.

According to the website for Sydney TMS, a clinic that has been running for nine years, treatment occurs in “a regular medical office suite” where the patient sits back and relaxes “in a large reclining armchair”.

A magnetic coil rests on the person’s scalp near the front part of the skull.

“We don’t even have to shave your hair,” the clinic advises.

“The typical treatment session lasts approximately for 40 minutes. After the session the person can carry on with their day as usual.”

Side effects

TMS is generally well tolerated and safe.

The Mayo Clinic advises that side effects “are generally mild to moderate and improve shortly after a session”. They tend to “decrease over time with more sessions”.

Common side effects are scalp discomfort and pain; headache; tingling, spasms or twitching of facial muscles and feeling light-headed.

The level of stimulation can be adjusted to reduce symptoms.

In some people who get frequent headaches or migraines “TMS triggers headaches, so treatments might need to be stopped”.

Serious side effects are rare but may include seizures; emotional highs called mania, particularly in people with bipolar disorder; and hearing loss if the ears aren’t well protected during treatment.

The clinic advises that “more study is needed to determine whether rTMS may have long-term side effects”.

For more information about the Medicare Benefits Schedule and rTMS, see here.