Head Injuries : Minor Head Injury

by Food and Drug Administration (FDA)

(Page 3 of 4)

Head Injury Task Force

Responding to concern by Congress about head injury, the U.S. Department of Health and Human Services early in 1988 formed a federal task force of members from 13 agencies. Gordon Johnson, M.D., director of health affairs at CDRH, represents FDA.

"We were asked to identify gaps in all aspects of head injury," says Johnson, "and to make recommendations about how best to fill those gaps if funding were made available."

In February 1989, the group reported the need for research in every area: prevention, basic biology, treatment, rehabilitation, and community services. It recommended that the government institute a "traumatic brain injury" category in reporting systems, designate a lead federal agency and establish an advisory group, encourage state and local participation, create a national network of 15 head injury research centers, organize a treatment system tied into the centers, and study and document financial issues.

While the task force was developing its recommendations, the U.S. Department of Education's National Institute of Disability and Rehabilitation Research was setting up five model research and demonstration systems for brain injury at: Baylor College of Medicine in Houston, Medical College of Virginia in Richmond, Mount Sinai Medical Center in New York City, Santa Clara Valley Medical Center in San Jose, Calif., and Wayne State University Medical Center in Detroit.

"At an annual cost of $1.5 million, the programs are now fully operational and provide rehabilitation research and comprehensive services from emergency care, through long-term rehabilitation, to re-entry into the community," says J. Paul Thomas, Ph.D., the institute's director of medical sciences and task force member.

Minor Head Injury

Older people are particularly susceptible to head injury that may go unnoticed, says Mark Schapiro, M.D., chief of the brain aging and dementia section of the National Institute on Aging. Not only are falls more likely because of failing eyesight, reduced agility, and degenerative disorders such as Parkinson's disease, but also the chance of brain injury from a fall increases in the elderly because the brain shrinks with age.

"The shrinking stretches the tiny blood vessels between the brain and skull," Schapiro says. "If one tears, blood collects, pressing on the brain. This happens in anyone, but to a greater degree in older people, especially the very old, because the vessels are already strained." Tearing can occur from a fall or when the brain jars back and forth against the inside of the hard skull, as in whiplash in a car accident.

Twenty years ago, Schapiro says, many elderly people with minor head injury went undiagnosed, though they probably had headaches and might even have seemed senile.

"Today, if we suspect a blood clot because an older person complains about a persistent headache, we can look for it with the CT scan," he says. "A good example is when former President Ronald Reagan fell from a horse last year. During a later medical checkup, a CT scan showed a collection of blood, which they drained, and he recovered."

In minor head injury, patients often spend little or no time in the hospital, make quick medical recovery, and are discharged without a perceived need for formal rehabilitation, according to New York researcher Kay.

But even though there may not be obvious problems, there may nevertheless be injury, such as widely scattered stretching or tearing of the brain's nerve fibers. This diffuse injury doesn't cause specific deficits such as language problems but results in a general disruption of the overall speed, efficiency, execution and integration of mental processes, Kay wrote.

"I'm convinced that everybody who gets hit on the head has some brain damage," says CDRH's Johnson. "Repeated injuries, such as a boxer receives, add up over time to cause some damage to some cells. This is true even if he's never knocked unconscious. But usually the damage is so small, microscopic or submicroscopic, there's no simple way to detect it."

To assess various kinds of damage, including minute damage not indicated by CT scans or MR imaging, researchers are investigating regional brain blood flow with nuclear scanning techniques: single photon emission computed tomography (SPECT) and positron emission tomography (PET), Johnson says.

(A radionuclide drug is given and tracked in blood through the brain by a scanner, which produces a cross-section or 3-D image. SPECT and PET are regulated by both CDRH and the Center for Drug Evaluation and Research, the latter taking the lead since it regulates the drugs.)

"If brain blood flow is less in one person than another, we don't really know what that means," Johnson says. "But if we measure a person one year, and then measure again at a later date and identify changes, that may be significant."

According to New York researcher Kay, the most effective handling of minor head injury is to educate the injured person and the family before discharge. He urged that patients be carefully evaluated and informed of the likely scenarios, not only for physical symptoms and recovery but also for cognitive, emotional and behavioral symptoms and recovery.

Dr. Judith Middleton of Tadworth's Court Children's Hospital in Surrey, U.K., wrote recently in Journal of Child Psychology and Psychiatry that when problems arise — whether behavioral, emotional or mental — "it might be salutary to ask routinely whether children have had a past blow to the head."

The accompanying article "Prevention: The Sure Cure" gives practical tips to prevent head injury.

About the Author

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