By Sandra Basu
WASHINGTON — New technology could allow clinicians to determine precisely what brain functionality has been lost after traumatic brain injury, according to a study conducted by the University of Pittsburgh Medical Center (UPMC) and funded by the Defense Advanced Research Projects Agency.1
Head injuries can lead to breaks in fiber tracts, cables in the brain that impact function; however, these breaks are not usually viewable through traditional imaging techniques, which makes it difficult for clinicians to know exactly what brain functions have been affected and to predict whether there is long-term damage.
Through clearer images produced by an imaging technique known as high-definition fiber-tracking (HDFT), developed by UPMC, researchers say they have been able to observe and compare the integrity of 40 tracts in the brain, then predict what brain functionality has been lost.
High definition fiber-tracking map of a million brain fibers. Photo courtesy of Walt Schneider Laboratory.
Walter Schneider, PhD, senior scientist at the Learning Research & Development Center and Professor of Psychology, Neurosurgery & Radiology at the University of Pittsburgh and University of Pittsburgh Medical Center, compared the process to an X-ray for a bone break.
“Nobody talks about mild, severe or moderate bone damage,” Schneider told U.S. Medicine. “I believe that is exactly what would happen with TBI down the line, because we would say, ‘OK, you have taken a hit, how big a hit and on which cables.’”New Scanning Technology Could Pinpoint TBI Injuries and Aid Recovery Cont
In the study published recently in the Journal of Neurosurgery, UPMC researchers described their use of HDFT with a single TBI patient who was injured when his all-terrain vehicle crashed, and he was not wearing a helmet. While he underwent other types of scans, it was only with the HDFT scan that clinicians could identify the fiber breaks that corresponded with the patient’s injuries and predict what these fiber breaks would mean for the patient’s recovery.
David Okonkwo, M.D., associate professor, Department of Neurological Surgery, University of Pittssburgh School of Medicine, examines a patient who sustained a traumatic brain injury in an ATV accident.
-Photo Courtesy of University of Pittsburgh Medical Center
“This novel approach successfully detected, visualized and quantified damage when previous methods (CT, structural MRI and DTI) did not provide these details,” the researchers wrote. “With HDFT, we identified a specific lesion of the corticospinal pathway in the corona radiata that was directly associated with the functional deficits in our TBI patient. The volumetric losses, as well as the number of fibers projecting from the motor cortices, were reduced in the injured side, correlating with the left upper-extremity weakness. The other methods focused on describing the basal-ganglia hemorrhage, but the patient’s hemiplegia (left-sided weakness) could not be solely explained by basal-ganglia damage. With HDFT, we could specify lesions to the corticospinal pathway adjacent to the basal ganglia and quantify their extent beyond the capabilities of current neuroimaging modalities.”
Co-senior author of the paper and UPMC neurosurgeon David O. Okonkwo, MD, said in a statement that, until now, clinicians had “no objective way of identifying how the injury damaged the patient’s brain tissue, predicting how the patient would fare or planning rehabilitation to maximize the recovery.”
Schneider said this type of knowledge would not only allow medical providers a way to design effective rehabilitation, it also would helps patients and their families better understand the scope of injuries. Without a wound and evidence of injury from a standard scan, the injury can be mysterious. In addition, it could rule out the potential of long-term effects from TBI in some cases.
“With a definitive biological diagnosis, potentially hundreds of thousands of warriors that have had a TBI would gain the assurance when all of their brain cables are scanned and found to be normal,” he said.
On the other hand, patients in which tract damage is found would be able to see it along with their medical team, Schneider said, adding, “if you can see your enemy, you are better able to defeat it.”
HDFT is still undergoing research, according to Schneider, who said UPMC researchers are working with Walter Reed National Military Medical Center and the Maryland Neuroimaging Center in an ongoing investigation.
1. Shin SS, Verstynen T, Pathak S, Jarbo K, Hricik AJ, Maserati M, Beers SR,Puccio AM, Boada FE, Okonkwo DO, Schneider W. High-definition fiber tracking for assessment of neurological deficit in a case of traumatic brain injury: finding, visualizing, and interpreting small sites of damage. J Neurosurg. 2012 Mar 2.[Epub ahead of print] PubMed PMID: 22381003.
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