Book contents
- How to Read an EEG
- Reviews
- How to Read an EEG
- Copyright page
- Dedication
- Contents
- Figure Contributions
- Foreword to the First Edition
- Preface
- How to Read This Book
- Part I Basics
- Part II Interpretation
- Chapter 7 Approach to EEG Reading
- Chapter 8 Describing Abnormalities
- Chapter 9 Artifacts
- Chapter 10 Normal Variants
- Chapter 11 Sporadic Abnormalities
- Chapter 12 Repetitive Abnormalities
- Chapter 13 Ictal Patterns (Electrographic Seizures)
- Chapter 14 Activation Procedures
- Part III Specific Conditions
- Appendix: How to Write a Report
- Index
- References
Chapter 11 - Sporadic Abnormalities
from Part II - Interpretation
Published online by Cambridge University Press: 27 September 2025
Book contents
- How to Read an EEG
- Reviews
- How to Read an EEG
- Copyright page
- Dedication
- Contents
- Figure Contributions
- Foreword to the First Edition
- Preface
- How to Read This Book
- Part I Basics
- Part II Interpretation
- Chapter 7 Approach to EEG Reading
- Chapter 8 Describing Abnormalities
- Chapter 9 Artifacts
- Chapter 10 Normal Variants
- Chapter 11 Sporadic Abnormalities
- Chapter 12 Repetitive Abnormalities
- Chapter 13 Ictal Patterns (Electrographic Seizures)
- Chapter 14 Activation Procedures
- Part III Specific Conditions
- Appendix: How to Write a Report
- Index
- References
Summary
Sporadic abnormalities may occur in singles, pairs, or abundance but are not repetitive. They indicate cortical dysfunction and in specific cases are associated with epileptic seizures (cortical irritability or seizure tendency). The key electrographic feature is sharpness as sharp or spike waves are associated with epileptic seizures (epileptiform abnormalities). Additionally, an epileptiform abnormality (unlike normal variants) disrupts the background, is associated with aftercoming slow waves, and has a physiological field. Based on their location, sporadic abnormalities may be classified as focal or generalized. Polymorphic slowing is a nonspecific marker of cortical dysfunction, and monomorphic (rhythmic slowing) may be associated with epileptic seizures. [107 words/713 characters]
Keywords
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- Information
- How to Read an EEG , pp. 151 - 172Publisher: Cambridge University PressPrint publication year: 2025
References
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