- Mechanism
- Shearing/Rotational forces (e.g., high-speed MVA, Shaken Baby).
- Differential density between gray/white matter causes axon stretching.
- Clinical
- Immediate Coma (GCS <8) post-trauma.
- Disproportionate deficit compared to initial CT findings.
- Diagnostics
- CT: Often Normal or subtle punctate hemorrhages.
- MRI: Gold Standard (SWI sequence). Shows microhemorrhages.
- Key Locations: Gray-white junction, Corpus Callosum (splenium), Brainstem.
- Pathology
- Axonal Retraction Balls: Swollen, eosinophilic axonal endings caused by interruption of axonal transport (visible within 12–24 hours).
- Amyloid Precursor Protein (APP) Staining: Accumulation of APP is a sensitive marker for axonal injury (visible within 2–3 hours).
- Prognosis
- Poor; major cause of Persistent Vegetative State.