[An autopsy case of traumatic subdural hematoma from arterio-venous malformation with diffuse axonal injury]

Diffuse axonal injury (DAI) is defined as widespread damage to axons in the white matter of the brain without focal injury such as contusion and acute subdural hematoma. A case of traumatic subdural hematoma from arterio-venous malformation accompanied by DAI is reported. A 58-year-old man was assaulted, and immediately lost consciousness, and remained unconscious during about 44 hours until his death. The autopsy revealed acute subdural hematoma (about 160 g) on left temporal lobe and left cingular, uncal and cerebellar tonsillar herniation, and tear and hemorrhage of the corpus callosum. Under this subdural hematoma, gray-whitish vascular lesion with subarachnoid hemorrhage was found. Histologically, this lesion was diagnosed as the arterio-venous malformation. Neuropathological examination of the corpus callosum, dorsolateral part of midbrain and superior cerebellar peduncle revealed DAI findings, such as swelling and ballooning of the myelin fibers, swelling and waving of axons, and retraction balls. Axon degenerations were also observed immunohistochemically by anti-200 kD neurofilament antibody. From the results, his unconsciousness from the moment of impact might be occurred from not only subdural hematoma but also DAI.