Diffuse axonal injury (traumatic axonal injury)
- Rotational acceleration/deceleration shears axons at interfaces of differing tissue density.
- Clinical state worse than CT (CT normal in 50–80% or shows a few small haemorrhages).
- MRI: SWI/GRE (haemorrhagic microbleeds: blooming), DWI (non‑haemorrhagic lesions), FLAIR.
- Adams–Gennarelli grading: grade 1: grey–white junction (frontal, temporal); grade 2: corpus callosum (splenium commonest); grade 3: dorsolateral midbrain/upper pons (brainstem), worst prognosis.