San Antonio residents who suffer from depression have historically had access to two clinical treatment options: psychotherapy and medication.
While those are still the first-line treatments for psychiatric disorders like major depressive disorder and other mental illnesses, behavioral health clinics have started offering a relatively new treatment for those whose depression doesn’t respond to therapy and medication: transcranial magnetic stimulation, or TMS.
TMS is a noninvasive treatment that uses magnetic fields to stimulate specific areas of the brain that are underactive during depression and other psychiatric illnesses.
The U.S. Food and Drug Administration approved TMS to treat major depression back in 2008, migraine headaches in 2013, compulsive obsessive disorder in 2017 and for smoking cessation in 2020.
And there’s a long list of behavioral and neurological disorders that researchers suspect could also benefit from the treatment, Parkinson’ Disease, epilepsy and post-traumatic stress disorder, just to name a few.
Since approval, behavioral health clinics in San Antonio have started offering the treatment for people with treatment-resistant depression, especially within the last few years.
In August, Family Care Center, a private behavioral health company operating 40 clinics in five states, opened a “TMS Center of Excellence” in Stone Oak. The clinic will offer TMS treatment, therapy and medication management. And clinicians will aim to advance understanding and best practices for TMS treatment.
Research on the efficacy and safety of TMS is growing, but there’s also lots that scientists still don’t understand about the mechanism behind TMS, or how it can be improved and standardized.
“We don’t completely understand how it works,” said Dr. Melissa Martinez, a psychiatrist and associate clinical professor at UT Health San Antonio. “If we did understand exactly how it worked, it would treat everybody who has depression. But not everybody responds, and that’s partly because we don’t completely understand what causes depression.”
The science behind TMS
In a small patient room inside Martinez’s clinic on Eckhert Road, a mini-fridge sized machine sits behind a bed connecting to an electromagnetic coil. During TMS treatment, the coil is placed against the patient’s head, sending repeated magnetic pulses into targeted areas of their brain.
A tic can be heard with each pulse. It feels like a small tapping sensation on your skin. The pulses can initially be a bit intense and uncomfortable for patients, Martinez said, but they get used to the sensation.
Transcranial Magnetic Stimulation (TMS) coils on the MagVenture machines are used in treating depression at this UT Health San Antonio clinic in the South Texas Medical Center. Credit: Vincent Reyna for the San Antonio Report
Certain circuits of the brain are overactive, and others underactive, in people experiencing depression compared to a healthy brain, Martinez explained.
The magnetic pulses from TMS are aimed at specific brain networks that tend to be underactive during depression. This includes a network of the brain called the left dorsolateral prefrontal cortex, a crucial part of our executive functions that support attention, planning, memory and self control.
Turning up the signal in this area of the brain seems to simultaneously turn down the signal in the networks that are overactive, like the default mode network, experts explained.
This network of the brain is active when we’re focused on our internal world, such as when we’re daydreaming or dwelling on negative thoughts and emotions instead of being focused on what’s happening around us. It tends to be overactive in psychiatric disorders like depression.
“That’s why people have difficulty paying attention to the outside world and engaging with others or making decisions,” Martinez said. “Because the circuitry involved in decision-making is not working as well. That’s why we try to trigger that circuit to start firing again … and shutting down the other circuit that is just involved in focusing on the internal.”
TMS is rarely if ever used as a standalone treatment, explained Dr. Reginald Lloyd, a psychiatrist at Family Care Center in Alamo Heights. It’s a final resort for patients that’s often coupled with talk therapy, medication or both.
Only about 3 to 5% of patients at Family Care Center patients receive TMS treatment, according to Jessica Miller, regional director for the center’s clinics in Texas.
Pros and cons
TMS has some advantages over medications for depression like selective serotonin reuptake inhibitors, or SSRIs. Though SSRIs are generally well tolerated, they can come with disruptive side effects like sexual dysfunction, insomnia and upset stomach, among others.
TMS treatment can cause some minor side effects that tend to resolve, like headaches, sleepiness, scalp discomfort and ringing in the ears. Some more extreme, but incredibly rare side effects like seizures, have also been observed.
“One of the reasons we studied it … is because people are tired of having sexual side effects from the antidepressants or nausea or constipation or dry mouth,” Dr. Martinez said. “And so it was one of the reasons it was studied as an alternative to medications, because the side effects are pretty well tolerated.”
Patients can also build up a tolerance to SSRIs.
“If you take an antidepressant, you may have to increase the dose, increase the dose, increase the dose, and then one point in time it may just stop working as [the brain] continues to take on the stimulus,” Dr. Lloyd said. “It becomes habituated and can stop working over time. Well, the neuron doesn’t have the ability to do that when you’re stimulating it with an electrical signal.”
But TMS also has some disadvantages, most notably its cost.
The singular TMS machine in Martinez’s clinic cost about $60,000. In her experience, patients paying out of pocket have to cough up between $10,000-$15,000 for a full course of TMS treatment.
“Whereas a course of fluoxetine [or Prozac] is $10,” she said. “It’s grown a lot in the private sector where people are able to pay out of pocket for it. We cater to a patient population that, one is not able to pay out of pocket for it, and two, insurance. It can be challenging to get insurance to approve it.”
Insurance company’s willingness to cover TMS treatment varies widely. If it is covered, insurance companies may require proof that medications and therapy have been tried and were not been effective treatments.
TMS treatment can also be time consuming. A standard course requires patients to receive the treatment for 20 minutes every day five days a week for six to nine weeks. Family Care Center offers an expedited protocol of more intense treatment over a five-day period, and researchers are working to develop similarly condensed courses of treatment.
It’s also worth noting that like medications, TMS treatment does not reduce symptoms for everyone, and the benefits don’t last forever for many.
According to Martinez, about 60-70% of TMS patients will respond, meaning they will see some reduction in their symptoms. About 30-40% will go into remission, meaning their symptoms will be substantially or totally reduced. And about half of patients will see their symptoms return after six months.
MagVenture’s Transcranial Magnetic Stimulation (TMS) machine is used in treating depression at the UT Health San Antonio. Credit: Vincent Reyna for the San Antonio Report
The future of TMS
Clinicians at Family Care Center are aiming to help standardize TMS treatment, looking to optimize factors that can vary like the intensity and frequency of the magnetic pulses, among several other factors. Family Care Center’s TMS Center of Excellence in Stone Oak will serve as the center for TMS research and education across the company’s 40 clinics.
Dr. Lloyd is optimistic about using TMS on the adolescents who may have concerns about starting medication.
“We have an epidemic of suicidal thinking and things like that in the adolescent population,” Dr. Lloyd said. “One of the big pushes we have at the company is to show the safety and efficacy of TMS in the adolescent population, because their brains are very plastic, and we’re seeing that they respond very well.”
For Dr. Martinez, TMS is another tool in treating depression, but its usefulness and access to the wider public will largely depend on its costs coming down.
“Could it become a first line treatment? There might be cases where it could,” Dr. Martinez said. “To be honest, the brutal truth is that probably comes down to expense.”