Hi Mark,

While they share some common symptoms, my neurologist and neuro-psychologist both consider PCS and DAI different conditions.

There are quite a few distinctions but here are the big ones:
1. Manner of injury: DAI is caused by the violent rotation of the brain inside the cranium (shaken babies, car accidents, etc...) as opposed to contact with an external object.
2. Unconsciousness: Unconsciousness is a major indicator of DAI. Ninety percent of DAIs never regain consciousness. The ten percent of us lucky enough to wake up have severe impairments compared to our pre-morbid function.
3. Damage: As opposed to PCS where damaged can be localized (focal point), DAI causes significant damage to all areas of the brain. In scans, the DAI brain shows considerable shrinkage and torn and damaged axons in all lobes.
4. Diffuse axonal injury is permanent. There is little improvement over time, even with therapy.