About half a million of the military personnel who were deployed to Afghanistan or Iraq experienced PTSD, which UT Health San Antonio neurologist Dr. Peter Fox says occurs when trauma causes changes in the circuitry of the brain. "Depression, schizophrenia, PTSD -- many disorders are appropriately conceived as the aberrant firing of a circuit," Fox said. "People get negative thoughts, and they just won't go away. There's some pathway that you wish would shut up, and it's not."
Fox is a professor in the Department of Radiology at UT San Antonio, the director of the Research Imaging Institute at UT Health San Antonio, and he recently studied a treatment for combat veterans with PTSD that uses his team's patented, MRI-guided, robotic-controlled transcranial magnetic stimulation (TMS) to target that aberrant brain circuitry with an electromagnetic field, called "navigated TMS." The imaging guides the robot arm to a specific location on the scalp. It then pulses magnetic fields through the skull, aiming at a small, specific area of the brain. The electrical currents disrupt neural activity, improving the symptoms of mental health disorders.
Professor (tenured) in the Department of Radiology
Joe R. and Teresa Lozano Long School of Medicine at The University of Texas at San Antonio
Director, Research Imaging Institute
Board-certified neurologist at UT Health San Antonio
In Fox's study, TMS was paired with a particular type of psychotherapy called prolonged exposure therapy, which he said also works by disrupting maladaptive neural pathways.
"If you get therapy, you're modifying a brain network. So that's what we were doing," Fox explained. "And with the TMS, what I expect is that we're inducing plasticity." Plasticity is a property that allows the human brain to change, reorganize, and rewire itself.
Fox's study involved 119 active-duty military and veteran participants with combat PTSD who were being treated in a 30-day residential program at Laurel Ridge Treatment Center in San Antonio. They were divided into two groups. All of the patients received prolonged exposure therapy, and all of them thought they were getting TMS, but only one group was actually getting magnetic stimulation. The other was getting what Fox called a "sham" treatment. Not even the technicians delivering the treatment knew who was getting TMS therapy. The results, he said, were clear.
"The 'sham' group got better, but the TMS group got better right away, faster," he said. "The curves began diverging in week one and just kept diverging." By the time the study concluded, 85% of those in the TMS group showed significant symptom relief, compared to 60% in the "sham" group. Three months later, three-quarters of the TMS group was still experiencing clinically significant symptom improvement, compared to 30% of the "sham" group.
"Prolonged exposure is clearly an effective treatment," Fox said. "Did we speed it up? Did we create a more fertile soil for it to do its work? I'd be inclined to believe that."
These improved outcomes may represent a breakthrough for active-duty military personnel who currently have to leave duty as a result of PTSD, Fox said. "Nobody wants them to leave. Nobody wants to have them go out on a medical disability. They want them to get better."
Up next: petitioning the Food and Drug Administration for approval. TMS therapy is already FDA-approved for major depressive disorder and obsessive-compulsive disorder, but it is not yet approved for PTSD. Fox and his research team are preparing to submit the results of this study, which were published in the journal JAMA Network Open, to the federal regulatory agency.
