Can We Distinguish Triphasic Waves From Other Generalized Periodic Discharges? Do We Need to?

Publisher: Lippincott Williams & Wilkins Country of Publication: United States NLM ID: 8506708 Publication Model: Print Cited Medium: Internet ISSN: 1537-1603 (Electronic) Linking ISSN: 07360258 NLM ISO Abbreviation: J Clin Neurophysiol Subsets: MEDLINE

Publication: <2000->: Hagerstown, MD : Lippincott Williams & Wilkins
Original Publication: [New York, N.Y.] : Raven Press, [1984-

Electroencephalography*; Brain Diseases/*physiopathology; Brain ; Humans

Summary: Triphasic waves are intuitively distinctive waveforms that fall under the umbrella of generalized periodic discharges. The ability to distinguish these waveforms consistently could be helpful if a specific underlying pathophysiology could be identified. However, scalp EEG and clinical observation have been limited in their ability to elucidate the underlying cortical physiology that leads to triphasic waves. Evidence from intracranial physiologic data and computational modeling suggest that these and other periodic discharges should be viewed not as strictly ictal nor non-ictal but rather on the spectrum between these two. Triphasic waves in particular appear to result from an abnormal balance between cortical excitation and synaptic transmission with input from functionally connected brain networks, such as the thalamocortical pathways involved in arousal. The practical implication of triphasic waves begins with acknowledgement of uncertainty and a rational approach should ask whether the pattern-or its treatment-might be creating harm.
Competing Interests: The author has no conflicts of interest to disclose.
(Copyright © 2021 by the American Clinical Neurophysiology Society.)

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Date Created: 20210622 Date Completed: 20210909 Latest Revision: 20230825

20230826

10.1097/WNP.0000000000000765

34155184