Early diagnosis of diffuse brain damage resulting from a blunt head injury.

Diffuse types of traumatic brain injury (TBI) are more difficult to diagnose than focal types in forensic postmortem examination, since macroscopic abnormalities may be minimal. In addition, most microscopic findings are not specific to TBI and are sometimes not obvious in cases when the survival period is short. Therefore, early diagnosis of diffuse TBI is most difficult. Histopathological and immunohistochemical examinations of various elements including axons, nerve cells, and glial cells in a sufficient number of blocks are indispensable. Mapping of changes in these elements with complicated focal lesions, even if the lesions are trivial, on anatomical diagrams would be useful. The combination of histopathological and immunohistochemical examinations as well as analysis of the exact history of the trauma, if possible, and elimination of other causes of death would lead to accurate diagnosis of diffuse types of TBI in cases when the survival period is brief.