Breakthrough research discovered that giving veterans oxygen therapy can improve their symptoms of post-traumatic stress disorder, or PTSD. The world-first Israeli study showed that hyperbaric oxygen therapy so improved the crippling condition in half of the participants so that they were considered cured of PTSD.

According to The Times of Israel, researchers at Tel Aviv University used hyperbaric oxygen chambers to treat 18 veterans of the Israel Defense Force who were resistant to previous treatments for PTSD. Their study, published Tuesday in the peer-reviewed  journal Plos One, found that the oxygen treatment was not merely psychologically effective, it also improved the brain’s microstructure and functionality in veterans suffering from PTSD.

Scientists say that this is the first time hyperbaric oxygen treatment has been evaluated in treating PTSD, and the study results are promising.  

“We’ve started in this research to treat PTSD in a way that seeks to effect on actual physical changes in the brain,” Dr. Keren Doenyas-Barak, a nephrologist and expert in hyperbaric oxygen treatment who was part of the study, told The Times of Israel. “This approach doesn’t rely on psychological tools. It’s biological, not psychological, so it represents something fresh.”

Doenyas-Barak said that the 18 study participants given oxygen were evaluated by standard symptom diagnosis and by brain scans, and both diagnostic tools showed marked improvement after 60 sessions of oxygen therapy. Half of those treated were no longer considered to have PTSD, she said.

PTSD is triggered by traumatic events that leave the brain in a state of arousal, which affects its elasticity. The oxygen therapy is thought to increase the plasticity of the brain, allowing wounds in the brain tissue to heal, says the Times.

“Today we understand that treatment-resistant PTSD is caused by a biological wound in brain tissues, which obstructs attempts at psychological and psychiatric treatments,” said Dr. Shai Efrati, who led the research. Dr. Efrati directs the Sagol Center for Hyperbaric Medicine and Research at the
Shamir Medical Center and his work focuses on the novel aspects of hyperbaric medicine and brain rehabilitation. He said that the therapy “induces reactivation and proliferation of stem cells, as well as generation of new blood vessels and increased brain activity, ultimately restoring the functionality of the wounded tissues.”

For the study, Efrati and his team recruited 35 combat veterans all suffering from PTSD that was resistant to psychotherapy and medications. They were divided into two groups, with both groups continuing psychological therapy. One group of 18 veterans also had 60 sessions in a hyperbaric chamber, five days a week.

The control group’s symptoms were assessed at the end of the study and researchers reported that they were basically unchanged. The symptoms in the group treated with oxygen declined significantly and half of these veterans were cleared of the PTSD diagnosis.

Experts say that the Israeli research may be the beginning of new hope for PTSD patients who are resistant to current treatment. As many as 500,000 U.S. troops who served in the Iraq and Afghanistan wars have been diagnosed with PTSD. An estimated 700,000 Vietnam veterans — nearly 25% who served in the war, required some sort of psychological care for the delayed effects of combat exposure. In the past PTSD was described as “shell shock” or “battle fatigue” or “post-Vietnam syndrome. It wasn’t until 1980 that the diagnosis become official.

Efrati said the research could also help develop better diagnostic tools for PTSD.