EEG features of nonconvulsive status epilepticus

Nonconvulsive status epilepticus (NCSE) is diagnosed in practice as an enduring epileptic condition with reduced or altered consciousness, but without major convulsive movements, and epileptiform discharges on EEG. In this article, an illustrative and paradigmatic case is presented with a focus on the main EEG features which should be considered when there is clinical suspicion of NCSE. Some clinical and neurophysiological tips are also provided in order to effectively differentiate between NCSE and other conditions. The clinical suspicion of NCSE may be supported by EEG recordings showing rhythmic and dynamic epileptiform activity. However, although a definitive diagnosis of NCSE cannot be made without EEG-based evidence, the "ultimate diagnosis" of NCSE relies on both neurophysiological and clinical features.