Minnesota hospitals launch "nation's largest" concussion study

Hennepin County Medical Center and the University of Minnesota are launching what's billed as the nation's largest study of concussions and traumatic brain injuries, combining discoveries in brain imaging, blood analysis and eye tests to find a more accurate way to detect the injuries' severity and long-term ramifications.

The two Minnesota institutions are joining with Chicago-based Abbott, a pharmaceutical and device manufacturer, which has studied whether "biomarkers" in blood show up after people suffer head injuries.

The study, announced Wednesday, will involve screening 9,000 trauma patients at HCMC and enrolling at least 1,000 of them for testing and follow-up evaluations one year later.

Patients will range from those suffering mild concussions who never lose consciousness to people in comas to those whose injuries resulted in no head trauma at all.

The goal is to eliminate vague descriptions for head injuries — such as "mild, moderate or severe" concussions — and to create a sophisticated testing protocol that could pinpoint an injury's underlying causes and the precise treatments needed, said Dr. Uzma Samadani, a study leader and neurosurgeon at HCMC.

" 'Mild, moderate or severe' doesn't tell you anything about what's actually wrong or how you treat it or how the patient is going to do," she said.

Roughly 2.2 million Americans seek emergency department care each year for traumatic brain injuries, or TBIs, according to the U.S. Centers for Disease Control and Prevention. But Samadani said a substantial number of trauma patients have head injuries that go undetected, perhaps because they suffered blows to other parts of the body that didn't initially present risks to their brains. Then later they report headaches or seizures.

"They don't even necessarily attach it to the day they were injured because … they broke their leg and they hit their head and they got so focused on fixing their broken leg that they didn't think about the component of brain injury," she said.

She also noted that a certain percentage of head trauma is simply missed by conventional imaging tools, and said the study aims to clarify that.

Samadani's prior research found that tracking eye movements with a camera could detect brain injuries that aren't visible through imaging with CT scans.

The study will include MRI scans not typically performed on brain injury patients to search for bleeding or other damage that often goes undetected. Patients also would receive blood tests with Abbott's experimental handheld device, I-STAT, which is designed to produce instant results at the bedside. The device searches for proteins associated with brain injury.

"When we put all of this information together, we will have a better understanding about brain injury that will help us treat patients now and in the future," said Dr. Thomas Bergman, HCMC's chief of neurosurgery.

Other U.S. studies are examining methods of concussion detection, including the TRACK-TBI study that is enrolling 3,000 patients at 13 centers nationwide. However, HCMC's study is the largest at a single site.

The eye, blood and imaging tests are not yet approved as clinical tests for brain injuries by the U.S. Food and Drug Administration. Nor are they the only ways to identify the depth of brain injuries. Studies also have found that scanning the brain's electrical activity and monitoring changes in brain fluid can help identify brain injuries.

But Samadani said those experimental methods require baseline testing, when patients are healthy, which makes them useful for high-risk occupations such as professional football or the military, but not for the broader population.

Screening of trauma patients coming to HCMC is expected to begin next month and continue for two years. Researchers will only receive thumbnail descriptions of trauma patients initially, and then approach them once they are stable about whether they will volunteer for the study. The collaborative study is being funded by Abbott as well as state and HCMC grants.

Healthy study participants have been taking the eye movement tests at HCMC recently to create baseline results for comparison to injured patients.

"Data have shown a connection between brain injury and abnormal eye movements," Samadani said. "With new high-resolution cameras, we can detect subtle differences in movement much more easily and objectively than in the past."

Jeremy Olson • 612-673-7744