Study on the possibility of concurrence of focal brain injury and diffuse axonal injury

Abstract

When a human receives a heavy impact on the head, a focal brain injury and/or a diffuse axonal injury (DAI) are caused. The focal brain injury is caused by partial strain of a brain and/or rapid pressure fluctuation inside the skull. DAI is widespread damage to the white matter of the brain and caused by the shear stress. A focal brain injury is usually associated with brain tissue damage visible to the naked eye. However, the pathological basis of DAI can be observed only under the limited condition, and the bases are very difficult to be found in morbid anatomy. DAI may be unnoticed when focal brain injury concurs. In this study, various impacts were given to a finite element human head model, the condition of causing the focal brain injury and DAI was evaluated using average acceleration and the duration of the head which obtained from the computer simulations, and the possibility of concurrence of both damages was verified. As a result of computer simulation which is based on judicial autopsy report, it was shown the possibility of concurrence of DAI and focal brain injury was high, even though the cause of death was judged as focal brain injury.