Examining TBI
By Jessica Zimmer
Radiology Today
Vol. 26 No. 6 P. 14
The CBI-M framework offers a more thorough assessment of traumatic brain injuries.
This summer, trauma centers across the United States are phasing in a different method to evaluate traumatic brain injuries (TBIs): the clinical, biomarker, imaging, and modifier (CBI-M) framework. The CBI-M retains the Glasgow Coma Scale (GCS), the current and sole method of evaluation. It adds information about biomarkers, indicators in blood tests to identify tissue damage; imaging, for CT and MRI images of concerns such as blood clots; and modifiers, notes on how an injury occurred and the patient’s medical history. The shift to a more comprehensive method of assessment has long been in the works. For decades, clinicians have said the GCS by itself is not sufficient to provide them with adequate information to assess a condition as complex as TBI.
“For 51 years, we’ve been using a unidimensional metric of measurement for TBIs. The GCS score doesn’t do justice to characterize the complexities of this type of injury. Expanding to a multidimensional framework gives us a richer set of findings. This allows us to treat patients more effectively,” says Michael McCrea, PhD, a professor of neurosurgery, codirector of the Center for Neurotrauma Research, and director of the Clinical Neuroscience Research Center at the Medical College of Wisconsin in Milwaukee.
McCrea was a member of the steering committee to develop the CBI-M, a project that lasted from 2022 to 2025. A team of 94 participants, including TBI experts and people with lived experience, from 14 countries, created the framework. The National Institute of Neurological Disorders and Stroke of the National Institutes of Health led this effort.
Medical imaging companies are responding to the CBI-M framework by sharing how their tools collect and analyze data that the CBI-M requests. As the CBI-M undergoes testing, refinement, and validation, these companies are asking how they can advance technologies. Jeffrey Bundy, CEO of United Imaging, recalls the first time he saw United Imaging’s uAI Vision 3D camera in action.
“I observed the assessment of an unconscious patient. We couldn’t get verbal, motor, or eye-opening responses from the patient for a GCS score. But the camera enabled rapid scanning of the patient’s head. This allowed us to quickly and easily get data about their condition. What else could we do with this and other tools, going forward?” Bundy says.
Data Driven
The imaging component of CBI-M moves far beyond a positive or negative CT scan by specifying the type and extent of damage to the brain caused by TBI. “A positive CT scan could mean a very small contusion or a major space-occupying hematoma,” McCrea says. “It helps to consider this together with issues that affect their recovery, like a history of depression.”
The CBI-M also takes into account how modifiers such as a patient’s history of substance use influences their outcome. McCrea says medical institutions around the United States are already implementing the biomarker pillar. This is because point-of-care blood tests can be conducted at a patient’s bedside in emergency departments.
“Certainly, CT scans are widely available at hospitals around the country, but we can go beyond CT and the GCS. A change in practice is needed, though,” McCrea says.
The main obstacle will be integrating it into clinical practice. This will involve more education and optimization of workflow.
“It will require strategy and work by skilled individuals to add elements of the CBI-M into the electronic health record,” McCrea says. “The CBI-M enables a richer characterization of each patient’s brain injury that can guide individualized treatment.”
As medical imaging companies encourage the use of their products to collect data for the CBI-M, they are advocating for them to be used only when necessary. “CT scans involve ionizing radiation. We want to use it where it matters, for the right patient, and (for) patients with the right criteria,” says Katie Grant, PhD, vice president of the MR business for Siemens Healthineers North America. “MRI is a little bit different. While there is no ionizing radiation involved, detection of a TBI can be challenging, and a lot of research still needs to be done. Luckily, there’s a lot of overlapping technical development for TBI with developments for detecting Alzheimer’s disease, neurodegenerative diseases, and the effects and risks of stroke.”
Improving Assessment
It is not easy to determine which patients should get CT and MRI scans for CBI-M assessment. “There is limited involvement in the research community due to a lack of data and reproducibility,” Grant says. “Large patient populations are needed to study which imaging techniques might work best and to develop a standard of care. It’s hard to reproduce TBI. You can’t put a patient through an experience that would cause them to suffer a TBI. But in order to train AI algorithms, large datasets are needed.”
AI algorithms can help to a degree. The tool reviews past similar cases and suggests when a current patient should get a CT or MRI scan. Yet the changes medical imaging companies are looking for are very subtle. Grant says, right now, AI needs more data to train on so it can improve. This is partly because many factors can alter CT and MRI results. “If a patient drinks a glass of water before an MRI or gets four hours of sleep rather than eight or eats fatty foods before medical imaging, all of this can change the brain measurements,” Grant says.
Siemens Healthineers is currently optimizing AI algorithms to automatically detect downstream aspects of TBI, such as brain hemorrhage. “These algorithms can be enabled with minimal user interaction by leveraging a zero-click workflow,” says Mark Palacio, senior director of CT product marketing and sales operations for Siemens Healthineers North America.
Before Siemens Healthineers developed these types of zero-click or “inline workflows,” radiology professionals had to manually reconstruct the images. This was a time-consuming process.
“Now, if our software detects an intracerebral hemorrhage, it flags it with no click necessary,” Palacio says. “This saves a tremendous amount of time for the radiologist. It also helps the doctor treating the patient, as well as the patient, who gets the care they need faster.”
Automation is a necessity for America’s hospitals. The number of radiologists and radiology assistants dropped sharply after the start of the COVID-19 pandemic.
“These positions can be vacant for a long time and for many different time shifts throughout the day,” Grant says. “Seeing what automation can do is better than trying with stop-gap solutions, like staff that are not fully trained on how CT and MRI equipment works.”
Mobilizing Care
In the United States, falls are one of the most common causes of TBIs. Such incidents lead to nearly half of TBI hospitalizations, especially for adults over 75. Motor vehicle accidents and assaults are also common causes of TBIs. Yet it is not predictable when and where a person may fall, get in a car crash, or get in a fight. It is not possible to place CT and MRI equipment on every street corner or at every bar.
It is possible to bring CT and MRI equipment to collect CBI-M data to locations where it is more likely people will suffer TBIs, such as a battlefield or a sports field. As a result, medical imaging companies are advancing their tools in cooperation with military and sports medicine physicians.
One of the best ways to do this is to make CT and MRI machines portable. Then they can be transported easily to sites. Such tools also allow a patient to be moved less after suffering a TBI.
Less movement means a lower risk of complications, since transport can lead to further injuries. Less movement also means fewer medical staff are needed. Typically, five or six staff may need to travel alongside the patient with a serious TBI as they are moved.
“One of the ways we make our CT and MRI equipment ready for physicians, no matter where they are, is to produce all machines with the same capabilities. This means that a scanner isn’t minimally configured, without the necessary software,” Bundy says. “Having top-ofthe- line capabilities right away is especially important in rural communities, where funds can be tight.”
Siemens Healthineers is already working closely with the NFL and MLB to design MRIs in tractor trailers that can be driven to sports fields. “We also have a portable, head-only CT called the SOMATOM on.Site. [It] is designed to be wheeled into neuro ICU rooms or can even be mounted into an ambulance in a mobile stroke unit,” Palacio says.
The ability to do CT imaging in an ambulance at the point of contact with the patient means the right treatment can either be delivered on the ambulance or prepared as quickly as possible when the patient arrives at a comprehensive stroke center. This can maximize the potential for a patient to recover more completely from a stroke.
For the past seven years, Siemens Healthineers has been collaborating with the US Department of Defense on improving one of the company’s core products, the Somatom go.Top CT scanner. This machine can be deployed on a battlefield in a customized, expandable shelter.
“The shelter and CT scanner are designed to modernize the combat support hospital,” Palacio says. “Before, a shelter had to be small and sited far out of the combat area. [This is] because the legacy shelters were not radiation shielded. An injured soldier had to be transported on a litter back and forth to undergo medical imaging. Having access to a shielded container and advanced CT scanning capabilities means that more soldiers will have faster access to a key modality to detect downstream impact of traumatic brain injuries. It will help military doctors do their job better, with less stress.” During a mass casualty event, a high-volume scanner such as the Somatom go.Top could scan more than seven soldiers in an hour.
Rehab Medicine
In Stony Brook, New York, Anne F. Ambrose, MBBS/MD, is hiring medical professionals to build a rehabilitation medicine department. Ambrose is a professor of neurology and rehabilitation, as well as the director of the Renaissance School of Medicine (RSOM) Clinical Leadership Academy at Stony Brook University. She is instituting a new system of triaging patients to determine the order of priority for treatment. The system will also indicate which patients are likely to develop persistent symptoms following injuries.
“The new CBI-M framework will help me and the RSOM team build a pipeline to take biomarkers and do medical imaging as needed, soon after a patient suffers a TBI,” Ambrose says.
Ambrose has found the most common age groups to suffer TBIs are young children, between the ages of 0 and 4, and adults over age 60. In some respects, the GCS fails in assessing infants and toddlers. Very young children may not be able to answer certain questions, such as, “What year is it?” The GCS can similarly fail to accurately assess older adults. They may have memory issues or exhibit a lack of motor responsiveness because of one or more preexisting mobility or cognitive impairments, diseases, or incidents of stroke.
Ambrose says even with a new framework to assess TBI, there needs to be a widespread effort in public health to raise awareness about the signs and effects of TBIs. “You can’t leave it up to the people who got injured to share in great detail how they are doing and how they were doing a few hours, a day, or a week ago,” Ambrose says. “They can take notes at times, but they may not be fully aware. They suffered a head injury. You have to teach parents, classmates, coworkers, and caregivers of older adults what to look for.”
If another person sees an individual exhibiting concerning behavior, such as not remembering where they are, they can bring the person in for evaluation, which may include medical imaging.
“Right now, I am interested in injuries in women’s sports. I want to design a study that examines this in large student-athlete populations. Women are more likely to get injured than men, across all types of sports. But they are also more likely to seek medical care after an injury,” Ambrose says.
Such a study could potentially lead to an effort to figure out which actions, rules, and moves in games would lead to TBIs. For example, heading—hitting the ball with one’s head—a soccer ball can be extremely dangerous.
“More information could also help teammates and classmates encourage injured athletes to do the correct things after sustaining a head injury, even if they don’t go to the hospital right away,” Ambrose says. “Such actions include active rest, like light walking, and reducing screen time.”
Youth Sport Concerns
Patients who “fight through” their symptoms tend to do much worse. They can experience longer, more frequent, and more serious episodes of amnesia. Ambrose did not realize how little training people working with student athletes received until she ran a sports camp training program for high school and athletic coaches 15 years ago, at Mount Sinai Hospital. She adds that middle and high school students have a much higher rate of head injuries than students in grades K to 5.
“They can be clumsy and not as resilient,” Ambrose says. “They also get injured at a far higher rate than professional players, whose experience, training, and sometimes genetics provide them with more resilience.”
The culture of physical education (PE) classes and sports activities often contributes to reinjury. “A coach or PE teacher may be reluctant to report a head injury because they are concerned that they, the school, or a student may be found at fault. When they say, ‘Get back up,’ to a student who fell down and hit their head or suffered a blow to the head, it’s likely the student may not be performing as well. They are more likely to be reinjured,” Ambrose says.
In addition, if a person incurs a second concussion before the first one has healed, the outcome may be worse. Still, not every incident requires a visit to a hospital or use of equipment such as a CT scanner.
“That’s where public education comes in,” Ambrose says. “It’s a good idea to explain the idea of CBI-M and what kind of information a doctor gathers. Use of the CBI-M and public education that talks about this framework gives lay people an idea of what problems to look for and what exams, like MRIs, may be needed.”
—Jessica Zimmer is a freelance writer living in northern California. She specializes in covering AI and legal matters.