[Indications for EEG in mental confusion and behavior problems]

Even in 1998 at the time of brain imaging, EEG recording is undoubtedly useful in clinical psychiatry when a true cerebral disease takes the form of an acute psychiatric disorder. Though the real place of EEG recording cannot be yet accurately quantified, it may help guide the diagnosis, as it is of either positive (ie, confirming the diagnosis via additional information) or negative (ie, rejecting various etiologies) value. Most of the time, only the former is considered in published studies. The clinical value of EEG recording in psychiatry emergency unit is therefore still not clearly established. The study of patients admitted during two years in the emergency unit at Sainte-Anne hospital (Paris, France) does not bring new conclusions, mainly because of bias in the modalities of admission and follow-up. As well, the role of EEG recording for the diagnosis of non-psychiatric diseases in psychiatry emergency units cannot be defined today. The authors review clinical situations where EEG recording is still highly advisable.