THE EEG. IN LATE POST-TRAUMATIC CASES

About one-half (48%) of late post-traumatic cases have abnormal EEGs. The presence of fracture or unconsciousness does not appreciably alter this percentage. Post-traumatic cases with epilepsy have a higher percentage of abnormal EEGs. and post-traumatic cases with headache have a lower percentage of abnormal EEGs. than the average. Post-traumatic cases with psychosis have a slightly greater percentage of abnormal EEGs. than do those without psychosis.

Late post-traumatic cases suffering primarily from headaches have essentially the same percentage abnormality of EEGs. as non-traumatic cases suffering primarily from headaches. Late post-traumatic cases suffering from psychosis (organic reaction type) have essentially the same percentage abnormality as non-traumatic cases suffering from organic psychosis. Late post-traumatic cases suffering primarily from epilepsy have essentially the same percentage abnormality as non-traumatic cases suffering from epilepsy.

In almost all post-traumatic cases having evidence of focal abnormality by ERG. either (1) the focus corresponded to the area of injury, (2) a fracture or skull deformity was found at the site of the focus, or (3) Jacksonian seizures were present involving the side opposite the focus.