医学英語のリーディングとリスニング

Traumatic brain injury, or as it is also known, TBI, is becoming the signature injury of the ongoing war in Iraq. Yet, ironically many of those who have suffered this injury walk away from the battlefield seemingly unscathed, and their condition is often either undiagnosed or inadequately treated. So what exactly is this injury that is both "traumatic" and "difficult to detect and diagnose" which would seem, on the face of it, to be mutually exclusive.

Traumatic brain injury is inextricably linked to the Improvised Explosive Device or IED, the weapon of choice among Iraqi insurgents. This weapon has caused a huge number of severe injuries among the coalition forces, and immediately obvious injuries include loss of limbs and open head wounds which can result in death. However, the combination of improved body armor and advances in the medical treatment of battlefield injuries has lead to a much high survival rate than would have ever been achieved in previous conflicts. Moreover, both individuals with obvious injuries and those with no apparent injuries may suffer the not so obvious traumatic brain injury.

How is this possible? The most insidious aspect of traumatic brain injury is that it can result from just being close to an IED which has gone off. Thus even those individuals without obvious injuries who have been protected by their body armor may also walk away from the battlefield with traumatic brain injury. This damage is caused by the powerful shock wave set off by the IED that travels through the body of anyone in its immediate vicinity. This shock wave can even cause damage at the cellular level of the brain in the form of intracellular microscopic bubbles and ultimately cell death. Many soldiers who suffer this type of damage appear to have escaped unharmed, are not counted among the wounded and may simply return to their regular duties unaware of the brain damage which they have suffered.

However, these individuals may, over the long term, start to exhibit symptoms associated with traumatic brain injury such as headaches, sensitivity to light or noise, behavioral changes and memory impairment. What is most worrying is that no one really knows how many soldiers are coming home with undiagnosed TBI and how their condition will progress. These individuals could number in the thousands or even the tens of thousands, and they represent a potentially huge drain on the American health and welfare system, an enormous loss of potential earnings due to the inability to hold a job and a burden on families struggling to cope with the disabilities of their loved ones.