WEDNESDAY, June 1 (HealthDay News) -- Using a sophisticated new
imaging technique, researchers were able to find previously
undetected changes in the brains of Iraq and Afghanistan war
veterans who had been diagnosed with mild brain injuries sustained
from blast explosions.
Although emphasizing that the researchers are "absolutely not
there yet," Christine Mac Donald, lead author of the study, said
that one day this imaging technique "could potentially be utilized
to assist a physician in making a diagnosis of traumatic brain
That, in turn, could help guide therapy and decisions about when
a soldier should return to duty, added Mac Donald, who is a
research instructor in the department of neurology at Washington
University School of Medicine in St. Louis.
But negative scans don't rule out traumatic brain injury (TBI)
as a diagnosis. So, for the time being, diagnoses should be made
based on a clinical history, including information on loss of
consciousness, memory loss, confusion and other symptoms, the
The study findings are published in the June 2 issue of the
New England Journal of Medicine.
"The collection of this data is a monumental achievement. Working in the chaos of war, the authors have extracted very high quality data from soldiers exposed to [traumatic brain injury] experiences," said Keith A. Young, vice chair for research in the department of psychiatry and behavioral science at Texas A&M Health Science Center College of Medicine. "It strikes the right note in pointing us to future diagnostic procedures."
Blast-related traumatic brain injuries, which have affected some
320,000 troops, are considered the "signature" injury of the Iraq
and Afghanistan wars. But there has been some debate over whether
some of these milder injuries -- concussions -- that impose no
visible damage can actually damage the brain.
The imaging technique employed for the new study -- diffusion
tensor imaging, or DTI -- looks at how water moves in the brain.
Certain patterns of movement indicate that neurons (nerve cells)
are damaged or intact.
The study involved 63 U.S. military personnel who had undergone
a mild traumatic brain injury in Iraq or Afghanistan who later
underwent diffusion tensor imaging in Germany. All had experienced
primary blast exposure (due to explosions) and another injury from
falling or a vehicular accident.
These people were compared with 21 soldiers who did not have a
clinical diagnosis of traumatic brain injury.
The researchers found abnormalities in 29 percent of the
patients who had been diagnosed with traumatic brain injury, but
not in the control group. And these abnormalities weren't visible
on conventional MRI exams.
The anomalies linked to explosive blasts were different from
those seen in civilians with mild brain trauma caused by falls,
sports injuries, car accidents and blows to the head. The
abnormalities changed over time but were still visible a year
later, the study authors said.
But at this point it's not clear whether the abnormalities mean
the brain has been damaged.
"The importance of this study is that it clearly delineates DTI [diffusion tensor imaging] as a valuable MRI procedure with potential to tell us about brain damage related to TBI [traumatic brain injury]," said Young, who is core leader for neuroimaging and genetics at the Center of Excellence for Research on Returning War Veterans in Temple, Texas. "We just have to figure out what DTI is telling us."
A letter to the editor in the same issue of the journal said eye
injuries suffered by soldiers in the Iraq and Afghanistan wars may
be going undetected.
That conclusion was based on examinations of 46 veterans who had
been injured in a blast explosion and who also had traumatic brain
injury. Eye injuries were found in 43 percent of the group.
The letter authors recommended that soldiers undergo extensive
eye exams upon returning from a war zone.
The U.S. National Institutes of Health has more on
traumatic brain injury.