ELECTROPHYSIOLOGY UNDER THALAMIC-STIMULAT ION OF POST TRAUMATIC VEGETATIVE STATES

We have studied the electrophysiological evolution, with the aid of lo ng-term, quantitative E.E.G. (Holter method) and sensory evoked potent ials (visual, auditory and somatosensory) on 25 severe traumatic head injury patients (initial Glasgow scale - between 3 and 5) aged from 5 to 42 years having evolved towards a persistent vegetative state and b eing object of a protocol of thalamic stimulation. Electrophysiologica l exploration was practised before placement of the stimulation, then at 2 weeks, 1 month, 2 months and finally 3 months after. The electrop hysiological parameters appear to have no predictive value on the clin ical evolution after stimulation. However, changes such as long-term q uantitative EEG as well as evoked potentials mostly precede-clinical p rogress when present. Cortical evoked potentials are the first to chan ge significantly (J15) followed by long-term quantitative EEG and brai n stem evoked potentials (J30); the latter improving more completely. Also the consideration of the chronobiological aspects of the recordin gs of the long term EEG allow the proposal of <<waking targeted>> stim ulations at the most favorable moments of the nyctohemeral period.