Chapter 14 - Encephalopathy

Summary

This chapter uses a case-based approach to describe electrographic patterns associated with encephalopathy. Global cerebral dysfunction (encephalopathy) is typically characterized by a “low and slow” record that is not specific to any particular etiology. Severe forms show background discontinuity, absence of a posterior dominant rhythm, and loss of reactivity. Generalized rhythmic delta activity (GRDA) and generalized periodic discharges (GPDs) with triphasic morphology (triphasic waves) are two common patterns seen in encephalopathic patients. As with other rhythmic and/or periodic patterns, it is important to recognize that these patterns may lie on an ictal–interictal injury continuum (IIIC) and may need appropriate management. Cyclical alternating pattern of encephalopathy (CAPE) is a pattern of spontaneously alternating background changes that may have prognostic implications.