traumatic axonal injury
traumatic axonal injuryA post-traumatic form of diffuse brain injury which affects the white matter, and is divided into three grades by histology.
Traumatic axonal injury
Grade 1: Abnormalities are identified by histology only.
Grade 2: Widely distributed axonal damage, plus focal lesion in the corpus callosum.
Grade 3: Diffuse axonal damage, plus focal lesions in the corpus callosum and the brainstem.
Immunocytochemistry for amyloid precursor protein A-beta-PP, which can be identified in all patients who survive 3+ hours after traumatic head injury. A-beta-PP can also be seen in infarction, hypoglycaemia, and HIV infection. Long-standing lesions can be identified by CD68, a marker of microglial activation.