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Chapter 16 - Ictal Patterns (Electrographic Seizures)

from Part II - Interpretation

Published online by Cambridge University Press:  24 June 2021

Neville M. Jadeja
Neville M. Jadeja
Affiliation:
University of Massachusetts Medical School
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Summary

Ictal patterns represent ongoing electrographic seizures. They are recognized by their clinical accompaniments (may be subtle) and electrographic features. Evolution is the electrographic hallmark of an ictal pattern, plus features (such as overriding fast activity) also render a pattern more ictal in appearance. Electrographic seizures will typically have a clear onset, evolution and offset. Conventionally, they should last for greater than 10 seconds. Electrographic seizures are common in after convulsive seizures, acute brain injury and in critically ill patients with altered mentation. Continuous EEG monitoring is the preferred method of diagnosing electrographic seizures. Typically, a duration of 24 hours is sufficient, but this should be extended in certain high-risk populations.

Keywords

ictalelectrographicevolutionplus features
Type
Chapter
Information
How to Read an EEG , pp. 149 - 159
Publisher: Cambridge University Press
Print publication year: 2021

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