Tuesday, September 25, 2007

TBI: Worse than we thought

Research scientists at Johns Hopkins have discovered that the effects of Traumatic Brain Injury (TBI) from exposure to bomb blasts are even more devastating than previously believed. The newest research shows that even when there are no outward signs of injury, brain cells can be altered, the cellular metabolism changed. Metabolic changes lead to a cascading effect, cells experience premature aging, and the result is neuronal death. Neurons do not replicate. Once a neuron is lost, it is gone forever.

The effects of this cellular demise are symptoms that may not be evident for months, or even years. The symptoms can range from vertigo, memory deficits and headaches to disorders of affect, such as anxiety, lethargy, and apathetic demeanor. "These soldiers could have hidden injuries with long-term consequences," says Ibolja Cernak, a scientist with the Johns Hopkins University Applied Physics Laboratory.

This latest research underscores the suspicion that many have expressed, that the number of Soldiers and Marines who have experienced or will experience the “signature injury” of this war may have been vastly underestimated up to now. Now consider that exposure to violent percussive incidents is not isolated in occurrence, but instead happens almost routinely. Some Soldiers and Marines have been exposed to up to twenty five separate blasts.

(more after the flip)

The most recent findings are the result of percussive experiments conducted on animals, then the animals were sacrificed and the brain tissue examined microscopically. In the animal studies, scientists have discovered a fundamentally different injury than the “concussion” wound that has traditionally been ascribed to exposure to explosions. A concussion is essentially a bruise on the brain that generally heals with time.

Brain damage at the cellular level is likely permanent – and will almost certainly lead to further neurological degradation over time. Put bluntly, G.I.’s afflicted by TBI are not likely to get better, and in fact will almost certainly get worse.

Since the first wounded veterans began returning, clinicians treating the wounded have noticed a pattern of symptoms emerging over time. Patients have been screened and found to be healthy; only to return with emerging symptoms at a later date.

To complicate matters further, because the physiological damage that underlies the symptoms occurs at the cellular level, the damage is undetectable by any imaging technique. "This is a new beast," said one San Francisco-based traumatic brain injury specialist who treated soldiers this year at an Army hospital in Germany.