The EEG is an invaluable tool in the diagnosis of epilepsy which guides clinical management. It helps to determine if attacks are of epileptic origin, allows the estimation of the recurrence risk after a first seizure, aids in the diagnosis of the epilepsy syndrome and represents the gold standard in the presurgical evaluation of epilepsy. The EEG can also detect subclinical seizures as a cause of coma. In this review we discuss the sensitivity and specificity of the EEG, present the EEG findings and their significance in different epilepsy syndromes including focal and generalized epilepsies and describe the application of activation procedures.
Keywords: EEG; epilepsy; focal; generalized; hyperventilation; medication; photic stimulation; sleep deprivation.