"Head trauma" refers to a head injury sufficient to cause prolonged unconsciousness or persisting brain dysfunction. Mild head injury without
unconsciousness rarely has lasting effects.
Fitness & Diving:
Two principal concerns exist:
1. Post-traumatic epilepsy. This risk is directly related to the severity of the injury and the time elapsed between the injury and your plans to dive. Penetrating head wounds with brain disruption have a high risk of post-traumatic seizure; head injuries resulting in brief unconsciousness do not. With mild head injuries, risk falls sharply with time; with penetrating head wounds, long-term risk is less predictable.
2. Cognitive loss. Defects in memory, understanding and concentration are obvious risks in diving. This is best evaluated by social, school and job performances. If these skills are intact, there is probably no reason to restrict diving. Diving in itself does not worsen the effects of head injury.
(Hugh Greer MD, Alert Diver, May-June 1999.)