SAN DIEGO — An advanced, high-tech scanner is providing a team of Navy, Veterans Affairs Department and university researchers with detailed pictures of brain activity that will better identify traumatic brain injury, the signature but often-invisible war wound.
Moreover, said a lead researcher, an initial study involving 55 military members and veterans with mild or moderate TBI shows that the advanced imaging scanner — using a technique called magnetoencephalography, or MEG — also can reveal and identify post-traumatic stress disorder.
“We have some exciting data ... that the MEG potentially diagnoses PTSD,” said Mingxiong Huang, professor and associate director of the University of California, San Diego’s MEG Radiology Imaging Laboratory, in a June 1 interview.
The initial study involved 55 military and civilian patients, ages 18 to 45, with mild to moderate TBIs. The group includes 23 patients, mostly Marines, who endured blasts from improvised explosive devices, which are among the common injuries reported by Iraq and Afghanistan war veterans.
Huang said VA recently approved extending the study, which began in 2007, for another four years, and the research team, which includes UCSD professor Roland R. Lee and Dewleen Baker, a VA and Navy researcher, hopes to broaden the study with additional patients and expand its research toward better understanding what causes PTSD. The team plans to publish its initial study next month in a professional, peer-reviewed journal.
“Can we make the ‘invisible’ injury visible?” Huang said. “Being able to see the injury is really a key start to help understand how the brain recovers from TBI. The treatment and diagnosis of TBI and PTSD may be very different.”
Although the study is preliminary, researchers hope to help diagnose brain injuries in countless wounded military veterans, including those with less-obvious injuries from blasts, falls and concussions.
“Six to nine months after the injury, the majority of people with mild TBIs become symptom-free,” Huang said. “The brain, as a system, can recover.”
“But 20 percent of people with TBI have long-term symptoms,” he said, noting those patients will require additional therapy or medications, and some may need treatment and therapy for PTSD. “Part of the problem is we cannot see the injury,” he added.
Meet the machineThe MEG system, a large machine that resembles a Transformers-size hair dryer, was originally designed for research into epilepsy, stroke and other brain disorders.
Unlike an X-ray, the MEG system is a noninvasive machine and passively records electrical activity in brain tissue.
The scanner can locate abnormal areas of low-frequency waves, which are telltale signs of injured brain tissue.
“The brain is like a huge network [that] has to communicate with each other,” Huang said.
Mild and moderate TBIs, like concussions and “closed brain” wounds from blasts, often go undetected by more conventional imaging machines — including MRI and computerized tomography, or CT, scanners. An MRI can show bleeding, but in most cases, it doesn’t see damaged “axonal injuries” such as torn or shredded brain tissue that often mark mild TBIs, Huang wrote in an article he co-authored in the August 2009 issue of the Journal of Neurotrauma.
Although TBIs are considered neurological wounds, PTSD is a psychological disorder. But patients diagnosed with either share related symptoms tied to damaged tissue in specific parts of the brain. Huang said MEG scans of PTSD sufferers show injuries in the four main parts of the brain, including the amygdala and hippocampus, which control emotions, sensory responses and memory.
“With the MEG, you can visualize these areas that are injured,” he said.
In one case, a 17-year-old football player who suffered three concussions complained of headaches, dizziness, fatigue, poor memory and changes in speech and language — but several MRI and CT scans came up negative for TBI. The MEG scanner revealed injuries in two areas of his brain.
Another case of negative clinical MRI and CT scans involved a 27-year-old Marine who was knocked unconscious when his Humvee hit an IED. He later suffered from anxiety, irritability, poor memory and sleep, fatigue, dizziness and depression.
The Marine wasn’t diagnosed with PTSD, but a MEG scan showed brain injuries consistent with TBI, and possibly PTSD.
Finding answersAfter now-retired Col. Gary Wilson survived an IED blast in Iraq, MRI and CT brain scans came up negative and showed normal functions despite the Marine officer’s symptoms, which included headaches, poor recollection and inattentiveness. In MEG scans, three parts of his brain “lit up” to reveal three injured areas that also reflected his symptoms, “so that explained very well the problems he was having,” Huang said.
For months after he returned from Iraq, Wilson struggled with short-term memory, migraines and poor sleep; he said he knew he had a concussion and was frustrated when MRI and CT scans came up negative for TBI. The MEG scans, which Huang conducted, revealed TBI and showed him what was happening in his brain, which explained the problems he was having.
Wilson said those results helped him begin the healing process.
“For me, it was important to know what was PTSD and what was TBI,” he said.
He credits therapies with improving his functions and even easing his PTSD.
“It made everything else less severe, because it didn’t add to the anxiety and to the frustration,” he said. “I’ve become less hypervigilant, and I started sleeping better.”
Although the MEG scanners provide more detailed information than conventional MRI machines, there are far fewer of them available around the country. UCSD’s lab has the only working MEG scanner in California. Each MEG machine costs about $2.5 million, but there are higher operating costs, Huang said.
Although Wilson wasn’t part of Huang’s initial study, he said he hopes VA and the military expand the research and enable broader use of MEG scanners to help diagnose other wounded warriors, especially vets who are still struggling through problems and symptoms that remain undiagnosed.
“You have to sort it out, but it’s so hard to do that until you know what it is,” Wilson said.