Joint Base San Antonio, Texas (Sept. 15, 2016) -- Three Army medical treatment facilities are currently enrolling participants in a study to test the effectiveness of the 'Stellate Ganglion Block' procedure on relieving the symptoms of posttraumatic stress disorder.The Stellate Ganglion Block procedure is occasionally used to treat PTSD symptoms at Army treatment facilities. Womack Army Medical Center, Tripler Army Medical Center, and Landstuhl Regional Medical Center will use the study to evaluate an estimated 240 participants over an 18 month period.The research study will evaluate whether numbing the stellate ganglion, a set of nerves and nerve cells at the base of the neck, is helpful in reducing symptoms of PTSD. The procedure is referred to as a stellate ganglion block (SGB).The stellate ganglion acts as a relay station for the "fight or flight" response and the SGB procedure has shown to control pain in the head, neck, and arms. Army Physicians recently published a paper describing a consecutive series of 166 service members with PTSD who were treated with SGB and roughly 70 percent of the patients were shown to have improvement in their PTSD symptoms."There is a critical need to address PTSD among service members and provide evidence-based effective treatments," said Dr. Bradford Walters, M.D., Ph.D., chief medical officer at RTI International and principal investigator of the project. According to Walters, "Stellate Ganglion Block has shown great promise in effectively treating PTSD in a few case reports and series, but to date, no rigorous, randomized, controlled trials have been reported in the literature."Although the SGB procedure has been used to treat PTSD symptoms at Army medical facilities, there has never been a scientific study to evaluate if the procedure is helpful or if the positive results are caused by a placebo effect.The randomized, three-year study will test and characterize the efficacy and acceptability of Stellate Ganglion Block for the treatment of PTSD symptoms. The research for the study is funded by a grant of over $2 million from the U.S. Department of Defense, Defense Medical Research and Development Program."If our study shows that the procedure delivers positive results and is acceptable for service members, providers, and families, Stellate Ganglion Block will represent a new treatment option for PTSD, with the potential for near-immediate relief of symptoms," said Kristine L. Rae Olmsted, research epidemiologist at RTI International and co-investigator of the project.