Researchers ‘Surprised’ by Extent of Damage
By Brenda L. Mooney
BETHESDA, MD — “Brain scars” were detected in more than half of the active-duty servicemembers who underwent magnetic resonance imaging (MRI) in a recent study, even though they had been diagnosed with blast-related mild traumatic brain injury (mTBI), not a more-serious condition.
During the conflicts in Iraq and Afghanistan between 2000 and 2015, mTBI, essentially a concussion, was diagnosed in more than 300,000 troops, according to the Armed Forces Health Surveillance Center.
While mTBI usually is diagnosed based on behavioral observations as well as patient recall of events, such as post-traumatic amnesia and loss of consciousness, the military has been seeking a better way to assess and diagnosis the condition.
That’s why Gerard Riedy, MD, PhD, from the National Intrepid Center of Excellence (NICoE) at the Walter Reed National Military Medical Center in Bethesda, MD, led a study to look at advanced brain imaging with MRI as a tool for assessing mTBI.
“Working at Walter Reed, I saw people with mTBI get routine brain scans, and I thought we could do better,” Riedy said. Results were published recently in the journal Radiology.1
The study team used MRI to look at 834 military servicemembers with mTBI related to blast injuries and compared them with 42 participants without any type of TBI. More than 84% of them reported one or more blast-related incidents, and 63% reported loss of consciousness at the time of injury.
Scans found white matter T2 hyperintensities, i.e., “brain scars,” in 52% of the mTBI patients. Cerebral microhemorrhages were observed in a small percentage, 7.2%, and showed increased incidence with TBI severity
“Blast-related injury and loss of consciousness is common in military TBI,” study authors wrote. “Structural MR imaging demonstrates a high incidence of white matter T2-weighted hyperintense areas and pituitary abnormalities, with a low incidence of microhemorrhage in the chronic phase.”
“We were really surprised to see so much damage to the brain in the mTBI patients,” Riedy recounted. “It’s expected that people with mTBI should have normal MRI results, yet more than 50% had these abnormalities.”
The research also uncovered pituitary abnormalities in almost one-third of the patients, 29%. Previous research has shown a decline in pituitary function in troops with mild brain injury, possibly related to blast-related trauma, according to the study.
“A scar on a brain scan is an objective finding,” Riedy pointed out. “We start with the objective and build a foundation for the correct diagnosis of mTBI and then bring in the subjective measures later.”
The study said it included radiologic observations from the largest advanced neuroimaging cohort of military TBI participants ever described, emphasizing, “Neuroimaging has the advantage of objective identification of lesions that potentially serve as biomarkers for TBI.”
Injured servicemembers already have benefitted from the discovery, he said, adding, “An objective measure of traumatic brain injury can lead to proper therapies.”
For the first time, he explained, patients can see what had been called the invisible wounds of war.