An experimental study on histopathological changes of diffuse axonal injury

Objective To investigate the indicators for identifying diffuse axonal injury by blunt forces in forensic pathological practice. Methods The DAI model was produced by the fluid - percussion method in cats. The cerebral samples were stained by H. E. , Bodian, Kluver - Barrera stain and NF Immunohistochemistry. Changes of axons and myeline sheath were observed at different intervals after injury. Positive NF immunostained area in axons was measured, and the data was analyzed by SPSS 11.5 for windows. Results Changes of axons in subcortical white matter and brainstem were observed in the forms of swollen, waved and distorted axons in early stage after injury (1-2 hours). Markedly torn, vacuolated axons with formation of the retraction balls from 4 hours after injury were specifically demonstrated in NF immunohistochemistry (P0.01).Conclusion The axonal changes including markedly tore, vacuolated axons with formation of the retraction balls was a specific indicator for identifying DAI.