By Tina Meketa, University Communications and Marketing
Through its partnership with U.S. Special Operations Command, the USF Institute of Applied Engineering has co-led an illuminating study that found repeated exposure to low-level blasts is associated with signs of brain injury in Special Operations Forces. Such exposure is common throughout many military careers, including in training and operational environments.
Often these injuries are not detected by conventional MRI scans, blood tests or neurocognitive measures – highlighting the urgent need to develop new diagnostic tests for Special Operations Forces at risk of brain injury.
“These particular blasts do not have as severe an impact as an improvised explosive device, but in repetition, across years of training and combat, they can have debilitating effects,” said Samantha Tromly, program director at the USF Institute of Applied Engineering. “While we can diagnose more severe traumatic brain injuries, we’re hoping to develop a quantitative test or panel of tests to diagnose repeated blast brain injury and help get these American heroes the help they need and deserve.”
Tromly comes from a family with a long line of military service. Her husband, Maj. Kevin Tromly, served in the U.S. Army as a field artillery officer for 15 years – including two, year-long deployments to Iraq. Her father served nearly four decades as an Air Force pilot, her sister is an Air Force nurse and her brother worked in Naval Acquisitions and currently works for NASA.
“They are my ‘why.’ I am forever indebted to the sacrifice of our men and women in uniform,” she said.
As part of the study published in the Proceedings of the National Academy of Sciences, Tromly managed a multidisciplinary team at Massachusetts General Hospital to collect data on 30 active-duty operators who represent the Army, Navy, Air Force and Marines over the course of three years. All participants had extensive prior combat exposure and reported high levels of cumulative blast exposure over the course of their careers.
The participants underwent brain imaging, blood tests and neurobehavioral analysis, such as tests on cognitive impairment, memory loss, PTSD, anxiety and depression – giving researchers a holistic view of what biomarkers they have in common.
The research team found that higher blast exposure was associated with alterations to the structure, function and neuroimmunology of the brain, as well as lower health-related quality of life. Although no specific blood-based biomarkers for brain injury were detected during the study, the researchers did find higher-than-expected levels of the protein, tau, in their blood – a finding that could help in their development of a portable diagnostic test for more immediate intervention.
Cumulative blast exposure was associated with changes in cortical thickness (left), functional connectivity (middle) and neuroimmune markers (right)
“These are American heroes who answered the call to serve after the terrorist attacks of Sept. 11, 2001, and fought the most dangerous missions of the War on Terror for two decades,” said principal investigator Dr. Brian Edlow, co-director of Mass General Neuroscience and associate professor of neurology at Harvard Medical School. “They deserve the best medical care, and while more research is needed, our results suggest that a diagnostic test for repeated blast brain injury is within reach.”
The research team is in the process of designing a larger study to develop a diagnostic test for repeated blast brain injuries – an effort that U.S. Special Operations Command recognized in their support of the study saying in part, “USSOCOM recognizes that the health and well-being of our elite special operations forces is a critical element to develop and employ the world's finest warfighters. Because brain health is a key element to fielding a healthy force, we want to help both the U.S. military and the medical community understand and identify signs related to repeated blast effect, benefitting all members of the U.S. military.”
The research team hopes to continue to work toward the ability to diagnose these injuries with the ultimate goal of providing earlier treatment options to help protect the long-term brain health of the members of the armed forces.