Academic literature on the topic 'Triphasic waves'

Periodic electroencephalographic (EEG) patterns are frequently recorded during ICU EEG monitoring in patients with altered mental status; these EEG features represent electrical discharges, ictal in appearance, occuring at regular intervals. They are known as lateralized periodic discharges (LPDs), bilateral independent periodic discharges (BIPDS), generalized periodic discharges (GPDs), continuous 2/s GPDs with triphasic morphology or triphasic waves (TWs) and Stimulus Induced Evolving Lateralized Rhytmic delta activity or Si-Evolving LRDA (previously SIRPIDS); other periodic, rhythmic patterns are Occasional frontally predominant brief 2/s GRDA (FIRDA previously), Lateralized rhythmic delta activity (LRDA) and Brief potentially ictal rhythmic discharges or B (I)RDs. The role of most (not all) of these EEG patterns is controversial; there is no consensus on which patterns are associated with ongoing seizure injury, which patterns need to be treated, and how aggressively they should be treated. Many authors consider these patterns as an unstable state on an ictal-interictal EEG continuum; the aim of the present chapter is to gain knowledge of these EEG features, show their association with known neurologic pathologies/syndromes and finally how to manage them.

Electroencephalography (EEG) is an important part of the evaluation of many disorders in infants and children, including seizures and spells. This chapter identifies abnormal epileptiform patterns seen in infants and children and correlates these patterns to specific seizure types and electroclinical syndromes. Generalized discharge (associated with genetic generalized epilepsies as well as epileptic encephalopathies), focal discharge (associated with benign focal epilepsies as well as lesional epilepsies), and hypsarrhythmia are discussed. Additionally, abnormal, but non-epileptiform patterns—including periodic patterns, triphasic waves, intermittent rhythmic delta activity, suppression, asymmetry, and slowing—are reviewed. Specific etiologies associated with various abnormalities on pediatric EEG are identified.