Incision-Free Brain Radiation Shows Promise for Treatment-Resistant Depression

Among the participants, 14 experienced severe depression that led to suicidal thoughts. After treatment, suicidal thoughts diminished in all but one participant. Overall, 89% of participants reported improvement in depression scores, with benefits sustained for a median of three years post-treatment. Dr. Mohamed Khattab, a radiation oncologist at the University of South Florida and Tampa General Hospital, emphasized the significance of finding a new option for individuals who have struggled with severe depression despite various previous treatments.

This research was presented at the annual meeting of the American Society for Radiation Oncology (ASTRO) and published in the International Journal of Radiation Oncology*Biology*Physics. The focus was on treatment-resistant depression, defined as depression persisting despite at least two antidepressant treatments. Approximately 30% of patients with depression may fall into this resistant category.

Participants had previously attempted a variety of treatments, including cognitive therapy, multiple medications, ketamine, transcranial magnetic stimulation, electroconvulsive therapy, and invasive procedures such as ablation. These treatments can involve side effects, some necessitating surgical intervention.

The study utilized a technique called stereotactic radiosurgical capsulotomy, applying concentrated radiation to create a small lesion in a brain circuit associated with mood and obsessive-compulsive disorders, without requiring surgery or implanted devices. This method has previously been used for obsessive-compulsive disorder but is novel for treating difficult depression cases.

In the study, after the treatment, 18 participants underwent evaluation and demonstrated an average 53% reduction in depression symptom scores. Notably, there was a significant decrease in suicidal thoughts. Dr. Khattab remarked on the meaningful reductions in symptoms and emphasized the absence of severe neurological or cognitive side effects typically feared in brain procedures. Participants exhibited no neurological deficits, personality changes, or cognitive decline post-treatment, a finding that Khattab identified as particularly important.

While three participants experienced mild side effects such as headaches or dizziness, two others had temporary changes in brain tissue, which were resolved with steroid treatment. The researchers acknowledged that the study lacked a comparison group, limiting the ability to definitively attribute improvements to the radiation treatment. Future, larger studies are warranted to explore this approach further.

Dr. Markus Bredel, co-chair of ASTRO's Functional Radiation Medicine Task Force, remarked on the significance of evaluating a targeted, incisionless treatment in patients with previous treatment failures. He stressed the importance of larger studies to determine how this method could be integrated into standard care.

Since these findings were presented at a medical meeting, they are considered preliminary until published in a peer-reviewed journal.