Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Blasts may cause brain injury even without symptoms

04.03.2014

Veterans exposed to explosions who do not report symptoms of traumatic brain injury (TBI) may still have damage to the brain's white matter comparable to veterans with TBI, according to researchers at Duke Medicine and the U.S. Department of Veterans Affairs.

The findings, published in the Journal of Head Trauma Rehabilitation on March 3, 2014, suggest that a lack of clear TBI symptoms following an explosion may not accurately reflect the extent of brain injury.

Veterans of recent military conflicts in Iraq and Afghanistan often have a history of exposure to explosive forces from bombs, grenades and other devices, although relatively little is known about whether this injures the brain. However, evidence is building – particularly among professional athletes – that subconcussive events have an effect on the brain.

"Similar to sports injuries, people near an explosion assume that if they don't have clear symptoms – losing consciousness, blurred vision, headaches – they haven't had injury to the brain," said senior author Rajendra A. Morey, M.D., associate professor of psychiatry and behavioral sciences at Duke University School of Medicine and a psychiatrist at the Durham Veterans Affairs Medical Center. "Our findings are important because they're showing that even if you don't have symptoms, there may still be damage."

... more about:
»Blasts »DTI »Medicine »TBI »Veterans »cognitive »exposure »injury »symptoms

Researchers in the Mid-Atlantic Mental Illness Research, Education and Clinical Center at the W.G. (Bill) Hefner Veterans Affairs Medical Center in Salisbury, N.C., evaluated 45 U.S. veterans who volunteered to participate in the study. The veterans, who served since September 2001, were split into three groups: veterans with a history of blast exposure with symptoms of TBI; veterans with a history of blast exposure without symptoms of TBI; and veterans without blast exposure. The study focused on veterans with primary blast exposure, or blast exposure without external injuries, and did not include those with brain injury from direct hits to the head.

To measure injury to the brain, the researchers used a type of MRI called Diffusion Tensor Imaging (DTI). DTI can detect injury to the brain's white matter by measuring the flow of fluid in the brain. In healthy white matter, fluid moves in a directional manner, suggesting that the white matter fibers are intact. Injured fibers allow the fluid to diffuse.

White matter is the connective wiring that links different areas of the brain. Since most cognitive processes involve multiple parts of the brain working together, injury to white matter can impair the brain's communication network and may result in cognitive problems.

Both groups of veterans who were near an explosion, regardless of whether they had TBI symptoms, showed a significant amount of injury compared to the veterans not exposed to a blast. The injury was not isolated to one area of the brain, and each individual had a different pattern of injury.

Using neuropsychological testing to assess cognitive performance, the researchers found a relationship between the amount of white matter injury and changes in reaction time and the ability to switch between mental tasks. However, brain injury was not linked to performance on other cognitive tests, including decision-making and organization.

"We expected the group that reported few symptoms at the time of primary blast exposure to be similar to the group without exposure. It was a surprise to find relatively similar DTI changes in both groups exposed to primary blast," said Katherine H. Taber, Ph.D., a research health scientist at the W.G. (Bill) Hefner Veterans Affairs Medical Center and the study's lead author. "We are not sure whether this indicates differences among individuals in symptoms-reporting or subconcussive effects of primary blast. It is clear there is more we need to know about the functional consequences of blast exposures."

Given the study's findings, the researchers said clinicians treating veterans should take into consideration a person's exposure to explosive forces, even among those who did not initially show symptoms of TBI. In the future, they may use brain imaging to support clinical tests.

"Imaging could potentially augment the existing approaches that clinicians use to evaluate brain injury by looking below the surface for TBI pathology," Morey said.

The researchers noted that the results are preliminary, and should be replicated in a larger study.

###

In addition to Morey and Taber, study authors include Courtney C. Haswell of the Durham VA Medical Center; Susan D. Hurt and Cory D. Lamar of the W.G. (Bill) Hefner VA Medical Center; Jared A. Rowland of the W.G. (Bill) Hefner VA Medical Center and Wake Forest School of Medicine; and Robin A. Hurley of the W.G. (Bill) Hefner VA Medical Center, Wake Forest School of Medicine and Baylor College of Medicine.

This research was supported by a grant from the Department of Defense, Joint Improvised Explosive Device Defeat Organization (51467EGJDO), the Department of Veterans Health Affairs Rehabilitation Research and Development (RX000389-01) and with resources of the Mid-Atlantic Mental Illness Research, Education and Clinical Center and W.G. Hefner VA Medical Center.

Rachel Harrison | EurekAlert!
Further information:
http://www.duke.edu

Further reports about: Blasts DTI Medicine TBI Veterans cognitive exposure injury symptoms

More articles from Health and Medicine:

nachricht Mobile phone test can reveal vision problems in time
11.02.2016 | University of Gothenburg

nachricht Proteomics and precision medicine
08.02.2016 | University of Iowa Health Care

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Production of an AIDS vaccine in algae

Today, plants and microorganisms are heavily used for the production of medicinal products. The production of biopharmaceuticals in plants, also referred to as “Molecular Pharming”, represents a continuously growing field of plant biotechnology. Preferred host organisms include yeast and crop plants, such as maize and potato – plants with high demands. With the help of a special algal strain, the research team of Prof. Ralph Bock at the Max Planck Institute of Molecular Plant Physiology in Potsdam strives to develop a more efficient and resource-saving system for the production of medicines and vaccines. They tested its practicality by synthesizing a component of a potential AIDS vaccine.

The use of plants and microorganisms to produce pharmaceuticals is nothing new. In 1982, bacteria were genetically modified to produce human insulin, a drug...

Im Focus: The most accurate optical single-ion clock worldwide

Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock which attains an accuracy which had only been predicted theoretically so far. Their optical ytterbium clock achieved a relative systematic measurement uncertainty of 3 E-18. The results have been published in the current issue of the scientific journal "Physical Review Letters".

Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock...

Im Focus: Goodbye ground control: autonomous nanosatellites

The University of Würzburg has two new space projects in the pipeline which are concerned with the observation of planets and autonomous fault correction aboard satellites. The German Federal Ministry of Economic Affairs and Energy funds the projects with around 1.6 million euros.

Detecting tornadoes that sweep across Mars. Discovering meteors that fall to Earth. Investigating strange lightning that flashes from Earth's atmosphere into...

Im Focus: Flow phenomena on solid surfaces: Physicists highlight key role played by boundary layer velocity

Physicists from Saarland University and the ESPCI in Paris have shown how liquids on solid surfaces can be made to slide over the surface a bit like a bobsleigh on ice. The key is to apply a coating at the boundary between the liquid and the surface that induces the liquid to slip. This results in an increase in the average flow velocity of the liquid and its throughput. This was demonstrated by studying the behaviour of droplets on surfaces with different coatings as they evolved into the equilibrium state. The results could prove useful in optimizing industrial processes, such as the extrusion of plastics.

The study has been published in the respected academic journal PNAS (Proceedings of the National Academy of Sciences of the United States of America).

Im Focus: New study: How stable is the West Antarctic Ice Sheet?

Exceeding critical temperature limits in the Southern Ocean may cause the collapse of ice sheets and a sharp rise in sea levels

A future warming of the Southern Ocean caused by rising greenhouse gas concentrations in the atmosphere may severely disrupt the stability of the West...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Travel grants available: Meet the world’s most proficient mathematicians and computer scientists

09.02.2016 | Event News

AKL’16: Experience Laser Technology Live in Europe´s Largest Laser Application Center!

02.02.2016 | Event News

From intelligent knee braces to anti-theft backpacks

26.01.2016 | Event News

 
Latest News

New method opens crystal clear views of biomolecules

11.02.2016 | Life Sciences

Scientists take nanoparticle snapshots

11.02.2016 | Physics and Astronomy

NASA sees development of Tropical Storm 11P in Southwestern Pacific

11.02.2016 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>