Diffuse axonal injury is caused by what mechanism?

Diffuse axonal injury is caused by what mechanism?

• A. Penetrating injury
• B. Acceleration/deceleration forces causing microscopic tears of axons
• C. Ischemic stroke
• D. Inflammatory demyelinating disease

Answer: (B)

Diffuse axonal injury results from rapid acceleration–deceleration forces that shear and tear axons across the brain. When the head undergoes sudden stop or rotational movement, different brain regions lag behind others, creating shear at axons—especially where gray and white matter meet. This mechanical tearing disrupts axonal transport and communication across widespread networks, leading to immediate unconsciousness and often a prolonged coma, even if there isn’t a single large focal lesion on initial imaging. It’s a diffuse, mechanical injury, not a penetrating wound, an ischemic stroke, or an inflammatory demyelinating process.

Diffuse axonal injury results from rapid acceleration–deceleration forces that shear and tear axons across the brain. When the head undergoes sudden stop or rotational movement, different brain regions lag behind others, creating shear at axons—especially where gray and white matter meet. This mechanical tearing disrupts axonal transport and communication across widespread networks, leading to immediate unconsciousness and often a prolonged coma, even if there isn’t a single large focal lesion on initial imaging. It’s a diffuse, mechanical injury, not a penetrating wound, an ischemic stroke, or an inflammatory demyelinating process.