Electroencephalographic evaluation in patients with impaired consciousness

Abstract

The electroencephalographic examination (EEG) records spontaneous electrical activity generated in the cerebral cortex. The EEG is abnormal in almost all conditions associated with impairment of the level of consciousness. When consciousness is impaired the EEG becomes slowed (episodic or continuous), unresponsive to afferent stimuli, amplitude diminishes until eventually becomes flat. Coma may have various causes. EEG is a diagnostic and prognostic tool in acute anoxic coma. EEG is the only diagnostic tool for detecting a non-convulsive epileptic status.