Symptoms of post-traumatic stress disorder (PTSD) can be severe and disabling. Although some individuals with this disorder respond to psychotherapy and/or pharmacotherapy, many with chronic, treatment-resistant symptoms do not.
Results from neuroimaging studies indicate that there is increased activation of a brain region called the amygdala in individuals with PTSD. Hyperactivity of this region is predictive of treatment-resistant symptoms. In addition, there is some evidence that chronic PTSD may increase the risk of developing epilepsy later in life.
Some individuals with treatment-resistant epilepsy have seizures that arise in the amygdala and hippocampus, key structures in the medial temporal lobe of the brain. In such patients, a neurosurgical procedure involving focused removal of a portion of the right amygdala and right hippocampus can decrease or eliminate seizures that originate in these locations. Targeting this specific region can be very accurate thanks to brain mapping technology and modern neurosurgical methods. Although some cognitive functions may change as a result of the surgery (some improving and others decreasing), seizure frequency can decrease dramatically and quality of life can markedly improve.
In a recent article in the journal Neurosurgery, Kelly Bijanki, Jon Willie, and colleagues report the results of neurosurgical intervention for treatment-resistant epilepsy in two patients who also suffered from decades of severe, treatment-resistant PTSD. The authors hypothesized that the neurosurgical procedure might alleviate symptoms of PTSD in addition to reducing the frequency of seizures.
One patient was a 62-year-old male veteran who became symptomatic with severe, treatment-resistant PTSD following a blast injury in Vietnam that killed colleagues. Sixteen years after he started experiencing PTSD symptoms, he developed treatment-refractory medial temporal lobe (MTL) epilepsy.
The other patient was a 42-year-old female with a 19-year history of severe treatment-resistant PTSD that started after witnessing fatal violence involving family members. She developed treatment-resistant MTL epilepsy 16 years after the onset of PTSD symptoms.
Neurosurgical laser ablation procedures were successful at decreasing or eliminating seizure activity in both patients. In addition, both patients experienced dramatic improvement in PTSD symptoms. The 62-year-old veteran noted less hypervigilance, a marked decrease in re-experiencing the traumatic event, and decreased avoidance behavior. He and his wife also reported substantial improvement in his depressive symptoms and general anxiety. He was able to participate in group cognitive therapy and interact with people. The female patient noted a remarkable decrease in hyperarousal, and improved cognition and mood.
Neurosurgical treatment of PTSD is not yet ready for clinical use. This is an invasive procedure that destroys specific brain regions. When this procedure is used for treatment-resistant epilepsy, cognitive changes can occur. In these cases, the benefits from controlling the seizures, which themselves can contribute to cognitive changes, outweigh the risks from treatment. Nonetheless, this study demonstrates that ablation of a specific brain region that is hyperactive in individuals with treatment-resistant PTSD can lead to dramatic improvement in severe, disabling symptoms.
Can a hyperactive right amygdala be targeted by nonsurgical treatments? Not currently, but researchers are working to develop surface-applied electrical or magnetic stimulation techniques that target specific brain regions. The possibility that hyperactivity in the amygdala could be quelled by a procedure similar to outpatient transcranial magnetic stimulation (TMS) is within the realm of possibility.
This work supports the concept that a severe environmental stressor can lead to disabling, behavioral symptoms associated with changes in activity of a specific brain region involved in emotional regulation. Reversing the change in brain activity might reverse some of the disabling behavioral changes. Of course, a less invasive method of changing the activity of the amygdala, as opposed to irreversible neurosurgical ablation, would be a preferred therapeutic method.
This post was written by Eugene Rubin MD, Ph.D., and Charles Zorumski, MD.
Bijanki, K.R., van Rooij, S.J.H., Ely, T.D., Stevens, J.S., Inman, C.S., Fasano, R.E., Carter, S.E., et al., (2020). Case Series: Unilateral amygdala ablation ameliorates post-traumatic stress disorder symptoms and biomarkers. Neurosurgery. 87:796–802.