Soldiers who have seen combat overseas often come back with the invisible wounds of war, including psychological and physical damage to their brains.

In the past 15 years, more than 300,000 members of the U.S. armed forces have been diagnosed with traumatic brain injury (TBI), according to the Armed Forces Health Surveillance Center.

New research out of the Walter Reed National Military Medical Center in Bethesda, Md., shows that more than half of military service members with blast injuries have a form of scarring on their brains.

The research, published today by the Radiological Society of North America, used magnetic resonance imaging (MRI) scans of the brains of 834 active military personnel with TBI from combat. Of those, 84 percent reported one or more blast-related health incidents while 63 percent reported being knocked unconscious from the injury.

Researchers discovered “brain scars,” or the presence of white matter T2 hyperintensities, in 52 percent of the patients.

The researchers also found abnormalities in the pituitary gland in almost one-third of the patients. Located in the base of the brain, the pituitary gland is regarded as the “master gland” of the endocrine system.

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Objective Finding in a Subjective Field

These findings, researchers say, give an objective sign to help specialists diagnose and treat soldiers and other patients with brain injuries.

Lead researcher of the study, Dr. Gerard Riedy from the National Intrepid Center of Excellence (NICoE) at Walter Reed, says the goal is to test currently available imaging methods and determine which are most accurate at identifying the signs of TBI.

Once determined, they will then design a slimmed down and portable version of the exam adapted for the military and the U.S. Department of Veterans Affairs (VA).

“The current diagnosis is based on subjective information. A diagnosis from an objective method like MRI would greatly enhance the possibility of treating veterans with the correct treatment paradigms,” Riedy told Healthline. “The TBI treatments and PTSD treatment paradigms can be vastly different. So in my book an accurate diagnosis is key to any hope at meaningful recovery.” 

Patients with traumatic brain injury show symptoms “as individual as the patients themselves,” including headache, fatigue, irritability, memory loss, and sleep problems, Riedy said. These symptoms can appear immediately after the injury and later develop into other complications.

Asked if certain branches of the military are more likely to endure head trauma, Riedy said it was a sensitive question and one he has been “advised to avoid.”

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Should Brain Scans Become Standard After Service?

To use these advanced imaging techniques on every service member with a brain injury depends on changing protocols in what is considered a notoriously slow-to-adapt military health care policy. 

“These MRIs are expensive and time consuming to perform and analyze. Evaluating all 300,000 service members who have TBI at our center with our one MRI system would not be possible,” Riedy said.

Despite the costly and lengthy process Riedy added that if it where his child diagnosed TBI, he would definitely opt to have the brain scan completed. 

In 2010, there was a $15 million effort to put three MRI systems into Afghanistan to examine soldiers closer to the point of their injuries.

“I traveled to the Netherlands to program the MRI scanner to perform a slimmed down version of the NCNC exam,” Riedy said. “Unfortunately, politics and military command issues and structure lead to very limited use of these scanners in the field.” 

Dr. Theodore Henderson, a Colorado-based psychiatrist and TBI researcher not affiliated with the Walter Reed study, said changing treatment protocols within the VA appears to be a slow process.

“I could imagine it taking decades,” he told Healthline.

Henderson believes soldiers should receive these scans on a routine basis, including prior to deployment and follow-up scans after a tour of duty to be quantitatively compared. The scans though, he said, should be single photon emission computed tomography (SPECT).

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TBI or PTSD? New Clues Available

The Walter Reed team says one key aspect of their findings is the ability to focus on post-traumatic stress disorder (PTSD). Distinguishing between TBI and PTSD is often difficult because symptoms can be similar. However, treatments for one are unlikely to work for the other, and may even cause additional harm.

Using SPECT technology, which has historically been controversial among neurologists, Henderson and other researchers were able to identify the difference between traumatic brain injury and PTSD in combat veterans. That research made it to Discover Magazine’s top discoveries of 2015, placing 19th.

The ability to distinguish between the two common conditions facing combat veterans makes a huge difference in treatment. In research published earlier this year, Henderson and his team found many pharmacological treatments — including antidepressants and antipsychotics — are harmful to people with TBI.

“Emerging treatments for TBI are more targeted and require an understanding of what portion of the individual’s brain is involved,” Henderson said.

He and other researchers have been testing new treatments for TBIs that have shown significant improvements in case studies.

When it comes to this field of research, Henderson would like to see the Department of Defense and NICoE pair up with outside experts, including research universities and corporations.

“[Veterans] deserve our gratitude and respect,” he said. “They have earned our highest level of medical care and compassion.”