Largest Single-Center Concussion Study Launched At Trauma Center In Minnesota
Robert Glatter, MD
There are over 2.2 million annual visits to emergency departments (ED) for traumatic brain injury (TBI), according to the most recent data from the CDC. While some patients will end up being diagnosed with concussions after their initial ED visit, the reality is that there currently is not a comprehensive or even standardized approach in the ED for patients who suffer a TBI.
But this may be changing soon.
Researchers at Hennepin County Medical Center in Minneapolis, and the University of Minnesota, in collaboration with Abbott, are embarking on a groundbreaking and comprehensive study that aims to identify the spectrum of brain injuries that occur in patients on arrival to the ED, and followed through to completion for up to a year after they are discharged from the hospital.
Their goal is to develop a multimodal approach to brain injury for use in the future, similar to the way a patient with chest pain presents to the emergency department and has a battery of tests including an EKG, blood work and possibly even a coronary CT angiogram or an echocardiogram.
The researchers’ aim is to develop a new standard approach for evaluating patients with a TBI in the ED, which will include blood-based biomarkers and eye-tracking technology to assess how well the brain is working, along with specialized imaging and cognitive evaluations to better detect early signs of concussion and allow for earlier treatment and referral. Detecting abnormalities earlier will better allow physicians to improve outcomes after a TBI, according to the researchers.
The researchers plan to screen 9,000 patients and enroll at least 1,000 as part of their ongoing study. Children, as well as elderly patients, will be included, ranging from those with mild concussions to those with severe brain injuries who are comatose. Those patients who are enrolled in the study will be followed for up to one year. Based on the numbers, this will be the largest prospective single-center study of TBI in the U.S. Track-TBI, a federally funded study, still represents the largest prospective multi-center study for TBI to date.
“We know that there are different types of brain damage that can occur after trauma, whether it’s a mild concussion or a severe injury,” said neurosurgeon Uzma Samadani, M.D., Ph.D., Rockswold Kaplan Endowed Chair for TBI Research at Hennepin County Medical Center (HCMC), associate professor at the University of Minnesota and one of the lead investigators of the study. “ Our goal with this study is to combine multiple assessment techniques to quickly assess the severity of brain injuries and enable clinicians to provide appropriate treatments.”
A Different Approach to Brain Injury
Samadani’s approach is to look at brain injury differently—using eye tracking as an early markerto detect abnormal function, as opposed to relying only on an imaging study such as a CT scan that is typically normal, even in the face of significant symptoms of a concussion, including nausea, dizziness or headache. Her approach is to employ eye tracking, which utilizes a high-frequency camera to map pupillary position as a patient watches a two-minute video on a monitor or iPad.
“Data have shown a connection between brain injury and abnormal eye movements,” said Samadani. “With new high-resolution cameras, we can detect subtle differences in movement much more easily and objectively than in the past.”
Samadani has been studying eye tracking technology with her start-up, Oculogica, which aims to develop a neurodiagnostic for evaluating patients with TBI. Their goal is to gain FDA approval for their eye tracking technology, and to be the first on the market with a FDA-approved device that can capture and detect abnormal eye movements immediately after a TBI, which may alert physicians and other health care providers to the earliest signs of a concussion.
Blood-Based Biomarkers: The New “Troponin” of Brain Injury
The researchers also plan to evaluate a range of blood-based biomarkers, since previous and ongoing research point to the potential utility of specific biomarkers indicating brain injury. Proteins released from cells that are injured in the setting of trauma–tau and t-tau–which both cross the blood-brain barrier, have already shown promise as early markers for concussive-force injury, typically peaking within one hour after a TBI. Measuring levels of this marker has shown promise for early detection of TBI based on recent studies.
“When someone experiences a head injury like a concussion, specific protein biomarkers will be found in the blood. If the protein levels are higher than normal, that may show a brain injury has occurred and serve as a warning bell that further evaluation is needed,” explained Beth McQuiston, M.D., the medical director of diagnostics at Abbott and co-sponsor of the study.
Abbott’s researchers are working on a blood test to detect specific proteins in the blood stream immediately after a significant brain injury. The researcher’s goal is to utilize Abbott’s point-of-care handheld portable device–the i-STAT—to achieve a result at the patient’s bedside. The i-STAT is currently in use in emergency departments throughout the U.S. to measure cardiac troponins within minutes after a patient’s arrival to the ED to evaluate for a heart attack or unstable angina. It can also be used to measure electrolytes such as potassium, sodium or creatinine, a key measure of kidney function.
“This type of commitment from clinicians, corporations and hospital systems represents a quantum leap forward in the response, identification and diagnosis of TBI,” said Rich Able, chief strategy officer at Stratos Group Seattle. “We’ve come quite far in the seven years since the Lystedt Law was first passed in Washington State.”
“Now all 50 states have a concussion law that gives parents, coaches, clinicians and school administrators the information necessary to properly guide them. The advent of important diagnostic technologies like Dr. Samadani’s eye tracker and Abbott Diagnostics’ i-STAT handheld protein marker will now enable clinicians to make key decisions in the care and handling of TBI patients,”added Able.
New Imaging Approaches
In the face of the need for newer, more advanced technique to evaluate the brain after a TBI, the researchers plan to employ specialized MRI scans to examine microscopic structural abnormalities and resulting metabolic derangements not visible on CT scans. The Minnesota Cpinal Cord and Traumatic Brain Injury Research Program will underwrite research into this specific area of TBI. Diffusion tensor MRI (DTI) is one technique that has already shown promise for evaluating white matter changes in the brain, while also reflecting metabolic abnormalities.
“Imaging tells us what the brain looks like, eye tracking tells us how well it’s working and blood-based biomarkers can tell us the nature of the damage,” said Thomas Bergman, M.D., study investigator and chief of neurosurgery at Hennepin County Medical Center. “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.”