Desynchronized EEG activity in a case of post-traumatic coma.

The EEG pattern of diffused low-voltage non-reacting fast activity is exceptional in comatose patients. The authors report on clinical observations, CT scan and neurophysiological findings in one case showing this EEG pattern after a severe head injury. In serial EEG recording it is shown a progressive shift from fast activity towards the alpha and theta bands. The presence of abnormal auditory brainstem responses and of CT scan signs of brainstem lesion suggest that this peculiar EEG pattern may be due to a brainstem lesion.