Treating Brain Injuries
Last month, when University of Southern California wide receiver Garrett Green bobbled the football on a key play against Washington State, red flags went up among the Trojans’ athletic trainers on the sidelines. Only minutes before, Green had tackled an opponent -- hard -- on a kickoff return. His sudden lack of coordination struck team trainer Russ Romano as a pretty likely sign of concussion.
FOR THE RECORD:
Concussions: An article in Monday’s Health section on new ways to prevent, diagnose and treat concussions said USC wide receiver Garrett Green was 19 years old. He is 21. —
Romano called Green to the sidelines, asked him a few quick questions and got back answers confused enough to take the senior from Chatsworth out of the game. The next day, Green took a battery of cognitive tests to check for concussion symptoms. When they showed some lingering effects of injury, the 19-year-old was ordered to sit out practice for at least a week. After that, Romano told Green, he could be reassessed for a return to the field.
It’s a dilemma faced by coaches at all levels and in all kinds of sports, by emergency medical technicians responding to the scene of a car crash, by supervisors called to the site of a workplace accident: This person looks fine on the outside, but has his brain -- lodged in its bony case and far from view -- been hurt?
Every seven seconds across the United States, the answer is yes.
Across Iraq and Afghanistan, U.S. military medics, platoon sergeants and unit commanders urgently ask their troops a battery of questions similar to those that Green got on the sidelines. In the wake of explosions, car bombs and other perils in those countries, they too get confused answers and detect lingering symptoms of concussion from service members, including some who have escaped blasts without so much as a cut.
For these troops, the concussive blast waves rippling outward from an explosion are causing brain injuries that look very much like concussions caused by sports collisions, falls and car wrecks. Deep inside their brains, they are wounded.
Through January 2009, nearly 9,000 U.S. troops in Iraq or Afghanistan had been evaluated or treated for traumatic brain injury, or TBI -- the catch-all medical term for concussions and more severe injuries cause by a forceful blow to the head. But the scope of the problem is almost certainly much larger. A recent assessment by the Rand Corp. estimates that at least 180,000 -- and as many as 360,000 -- U.S. troops serving in those wars may have sustained a head trauma capable of causing brain injury.
That has put the Pentagon and the Veterans Affairs Department, which provides care to those returning from combat, on high alert to an injury that is epidemic among civilians. Their substantial budgets have funded a host of projects that promise to improve the prevention, diagnosis and treatment of traumatic brain injury well beyond the battlefield, brain injury experts say.
For the first time, medical professionals serving on the sidelines of sports and front lines of war are huddling with gadget geeks, neuroscientists and rehabilitation experts at confabs regularly called by the Pentagon.
The results are promising new approaches to curbing the silent epidemic of traumatic brain injury.
Better helmets: Until very recently, the helmets worn by soldiers and Marines were designed only to protect the head against penetrating wounds such as bullets or shrapnel, not impact. Newer helmets are making use of impact-absorbing designs widely devised for head protection in collision sports such as football. They include pads made from dense, spongy materials and webbed infrastructures that allow the helmet to absorb a blow without hitting the head.
More ideas may be coming off the fields of athletic battle -- improving protection there in the process. This summer, Major League Baseball began to adopt a batting helmet already in use by high school and youth leagues. Designed to withstand the impact of a 100-mph fastball, the helmet has a composite liner and harder shell.
Youth sports may yield another approach to head protection in combat: A helmet designed by the Boston-based firm Xenith Inc. uses a snug-fitting shell lined with small air bags. The pads surrounding the head adapt to the strength and location of impact. When hit from the outside, the pads inside expel a varying flow of air through tiny holes; the pads closest to the impact point compress to cushion the head, but slowly enough to slow the deceleration of head and brain in a collision.
Developed by a physician who played quarterback for Harvard University, the Xenith design is in use this fall by about 15,000 college, high school and youth league players. Designer Vin Ferrara anticipates that Pentagon grants will enable him and other helmet innovators to adapt some of their designs to the military’s needs.
One more innovation may come from race-car driving. Among the most damaging brain injuries are those caused by rapid side-to-side movement, causing the brain to twist, rotate and then slam against the skull. Since the1990s, a growing number of auto racers have been using a helmet and brace that help stabilize the head and neck during crashes, spinouts and rolls.
“I wouldn’t be surprised if there weren’t some kind of device that could instantly stabilize the head in instances of blast,” says Dr. Kenneth Curley, the Army’s neurotrauma research chief. As helmet design adapts, soldiers “are going to look more and more like storm troopers,” he says.
Neuroprotectants: Neuroscientists have tried mightily, but without success, to discover some drug that can “harden” the brain against knocks or, following an injury, disrupt the cascade of events that leads to brain cell death. “Neuroprotection” is an idea the Pentagon loves as well, and has funded studies to explore.
One of the chemical candidates now under intense scrutiny is progesterone, the steroid hormone that surges through women when they are pregnant and helps govern the menstrual cycle. Progesterone’s effects appear to help protect women from stroke, and in lab animals, to reduce the severity of spinal cord injury. Scientists believe progesterone does so by quieting brain cells that respond to injury with spasms of furious and self-destructive electrical activity.
Because the large majority of ground combat forces are male, the Pentagon will be looking at evidence largely from “non-feminizing” variants of the hormone progesterone.
Testing for vulnerability to brain injury: What if genetic testing could identify those who are at higher risk of poor outcomes from traumatic brain injury? Recognized early, such a predisposition might prompt one to take up tennis rather than football, to forswear motorcycles for cars with excellent safety ratings, to pursue a career, say, in neuroscience rather than in the military.
Duke University neurologist Dr. Daniel Laskowitz leads a team that several years ago found a genetic variation that predisposes a person to Alzheimer’s disease. More recently, Laskowitz and his team discovered that those with the same gene variant were likely to suffer worse consequences of stroke and traumatic brain injury.
Such findings are of considerable interest to the armed services, because they would help steer more vulnerable service members to less risky jobs. But though such tests have the power to protect, they also raise ethical issues surrounding the right to discriminate on the basis of distinctive genetic profiles.
As an Air Force doctor stationed at Balad Air Force Base in Iraq, Duke University’s Gerald Grant said he “got tired of seeing guys with three, four, even five blast injuries.” By then, Grant said, many of the cognitive effects of TBI were likely to be permanent, and worse than they might have been had the service member been taken out of harm’s way long enough to heal.
The problems: Medics can’t always tell who’s suffered a concussion or worse, and soldiers and Marines in battle are often unwilling, or unable, to acknowledge how badly injured they are. CT scans are the most reliable means of detecting bleeding in the brain, but they’re not available near the battlefield. And CT scans have another shortcoming: Though useful in alerting doctors to the potential need for surgery to remove a blood clot in the brain, they rarely reveal signs of mild brain trauma.
How, then, to detect, diagnose and distinguish the severity of brain injury? Pentagon-funded research is focusing on several possibilities:
Cognitive tests: To detect concussion, the sports world has ImPACT, a battery of neuropsychological tests that a player can take on a hand-held computer on the sidelines. It’s a lot more precise than “how many fingers am I holding up?” But in its current form, ImPACT is time-consuming and costly and may not travel well on the battlefield. Until the test is battlefield-ready, the military has issued all of its medics in the field a MACE card -- that’s Military Acute Concussion Evaluation -- an inventory of questions to ask and symptoms to look for to detect the daze of brain trauma.
Cornell University neurosurgeon Jam Ghajar, executive director of the Brain Trauma Foundation, has devised a test that may detect the cognitive effects of traumatic brain injury without a series of questions. The device is a pair of goggles, strapped around the head, that simultaneously projects a moving tracking ball and gauges the eye movements of the person watching it. The device readily detects what Ghajar argues is a hallmark of brain trauma: a victim’s poor performance at anticipating and responding to predictable movement. In the severely concussed, jerky eye movements replace the smooth visual tracking of the projected ball as it changes course. Critics counter the test may be a better measure of fear, anger and attention problems -- all in plentiful supply on the battlefield.
Imaging: With Defense Department funds, Ghajar and others are also exploring better, more sensitive ways of detecting brain injury with new and existing medical imaging technologies. Those include the use of functional Magnetic Resonance Imaging (fMRI), which can detect disruptions in blood flow of an injured person’s brain; magnetic resonance spectroscopy, which measures the metabolic changes in the brain that come with trauma; and Diffusion Tensor Imaging, a modification of MRI that zeros in on the brain’s white matter -- the dense connections between neurons that tend to rip and tear with concussion.
Such high-tech improvements may help identify where and how severely the brain has been injured in an accident, guiding treatment and rehabilitation. But they are likely to be of greatest use in a specialized trauma center, once a patient has already been identified as having brain injury.
Biomarkers:Of immediate use on the battlefield, in emergency departments and even on the sidelines of playing fields, says Grant, would be a simple blood test capable of distinguishing brain injury that will likely get better on its own from brain injury requiring immediate medical attention, and possibly surgery. That effort is part of a wide-ranging hunt for “biomarkers,” or readily measured physiological changes, that might reveal the presence and severity of TBI.
Already, a test of a protein in the blood called SB-100 is widely used in Europe, though not yet approved for use in the U.S. Last month, Grant presented evidence that a test that included two other biomarkers would reliably identify patients with brain injury that should be transported immediately to a trauma center.
The development of a revealing panel of biomarkers would have a dramatic effect on the diagnosis and care of those hurt in car crashes, falls and sports injuries.
“This is a huge dilemma for ER physicians,” says Duke’s Laskowitz.While most patients coming to emergency rooms with apparent concussion can safely be allowed to go home and rest, a few will have life-threatening injuries that can progress without aggressive treatment, he says. Physicians already have a rapid blood test capable of revealing whether a person appearing in the ER with chest pains has had a heart attack, “We need the same kinds of tests to help guide those early management decisions in the head-injury arena,” Laskowitz says.
For some, it will take more than rest and relaxation to recover from brain injury. Repair and rehabilitation will limit the extent and the persistence of disability, and both represent the final frontier of the Pentagon’s efforts.
At a scientific conference in early September called by the Pentagon, Clemson University bioengineering professor Ning Zhang offered an innovative new way to reduce TBI-related disability: by plugging the holes in the brain that trauma can leave behind.
In Zhang’s population of lab rats, trauma had killed off vast colonies of brain cells, leaving blank spots in their brains. Many were unable to see, smell, hear or feel stimuli, or to respond to them. With a background in materials science, Zhang and her team injected those holes with a gel made up of both natural and synthetic materials. The gel not only spurred the growth of stem cells to regenerate brain tissue; it provided a structure within which those regenerated cells could grow.
Within 12 weeks, the injured rats were as good as new, said Zhang, who said the strategy of plugging holes could treat head injury caused by car accidents and falls as readily as it would treat head wounds and trauma sustained in combat.
Another treatment prospect being explored by the Defense Department may seem offbeat, but has the strength of several early studies to commend it. In a clinical trial about to begin at the San Antonio Military Medical center, veterans suffering persistent and chronic cognitive symptoms of TBI will spend five sessions a week for six weeks in a hyperbaric oxygen chamber -- the treatment used to cure divers of the “bends” and used with some success on burn victims.
The aim: to boost blood flow to brain cells that surround a central injury area and lie dormant following an injury. These idling neurons, sometimes called the “ischemic penumbra,” aren’t dead, but their low level of activity can cause disabilities that need not be permanent, if they can be coaxed back to life.
The Defense Department has so far invested heavily in the front-end issues of brain trauma -- prevention, detection and acute treatment, says author Michael Paul Mason. “Nobody does it better,” he says.
“You’ll hear veterans talk about it being like they fell of a cliff. They have this great, great care and then, boom! It’s gone,” says Mason, who wrote “ Head Cases,” a book about the challenges faced by those with traumatic brain injury.
The long-term care of those with persistent disabilities from brain injury can be a long and costly commitment -- a fact the U.S. military is just now beginning to face. One Harvard economist has estimated that the lifetime care of each veteran disabled by brain injury could well cost $3.4 million.
It is a burden that many civilian brain trauma victims and their families have shouldered with little or no help from the government.
The Brain Injury Assn. of America, the leading advocacy group for patients and their families, has sought to reframe Americans’ understanding of traumatic brain injury as a chronic illness -- rather than an isolated event such as a broken leg. Like those with mental illness or developmental disabilities -- people with whom brain injury victims are often confused -- the brain-injured may have lifelong medical needs and a recognizable disease progression, the BIAA asserts.
That’s a view the U.S. government -- with its lifelong commitment to care for veterans’ health -- effectively endorses.
As the Pentagon and Veterans Affairs ponder how best and most efficiently to care for thousands of veterans disabled by brain injury, many civilian activists hope the agencies will fund research on practices that work, then help build the capacity to care for disabled veterans in their own communities -- alongside civilians also struggling with brain trauma. Already, a few such programs exist.
“The challenge is bigger than either community has,” says Mason, one of only 200 public-sector caseworkers in the U.S. who specialize in assisting the brain-injured.
In April, the Defense Department gathered rehabilitation experts from across the United States and Canada to begin to distill existing lessons from civilians in the field and chart a course for future research.