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 9 - Artifacts
from Part II - Interpretation
Published online by Cambridge University Press: aN Invalid Date NaN
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
Artifacts are noncerebral waveforms that may mimic or obscure cerebral activity. External (nonphysiologic artifacts) are produced outside the body whereas internal (physiologic artifacts) are produced by body organs other than the brain. Electrode artifact may have a spiky, periodic, or rhythmic appearance. Characteristically, it is limited to the involved electrode with no field. Sweat artifact may involve multiple. Eye movement and glossopharyngeal artifact may mimic frontal rhythms. EKG artifact (corresponding with QRS complexes) may be confused with periodic discharges. Ventilatory artifact may be confused with bursts of cerebral activity. Characteristically, it corresponds to the respiratory rate. Head tremor presents as occipital predominant rhythmic artifact. Maneuvers and devices such as bed-percussion, continuous renal replacement therapy, and extracorporeal membrane oxygenation, CPR, and even brushing teeth may lead to ictal appearing rhythmic artifacts. Discharges associated with cortical myoclonus are best appreciated in the central channels as these are relatively free of muscle artifact. Chewing artifact may electrographically mimic a generalized tonic clonic seizure. Close observation of the patient and the surrounding equipment either in person or on video is the key to diagnosing the cause of an artifact and avoid misdiagnosing it as cerebral activity. [191 words/1168 characters]
Information
- Type
- Chapter
- Information
- How to Read an EEG , pp. 95 - 119Publisher: Cambridge University PressPrint publication year: 2025
References
Britton, JW, Frey, LC, Hopp, JL, et al. Electroencephalography (EEG): an introductory text and atlas of normal and abnormal findings in adults, children, and infants. American Epilepsy Society, Chicago; 2016.Google ScholarPubMed
Tatum, WO, Dworetzky, BA, Schomer, DL. Artifact and recording concepts in EEG. Journal of Clinical Neurophysiology. 2011 Jun 1;28(3):252–63.Google ScholarPubMed
White, DM, Van Cott, CA. EEG artifacts in the intensive care unit setting. American Journal of Electroneurodiagnostic Technology. 2010 Mar 1;50(1):8–25.CrossRefGoogle ScholarPubMed
Nakamura, M, Shibasaki, H. Elimination of EKG artifacts from EEG records: a new method of non-cephalic referential EEG recording. Electroencephalography and Clinical Neurophysiology. 1987 Jan 1;66(1):89–92.10.1016/0013-4694(87)90143-XCrossRefGoogle Scholar
Ebersole, JS, Bridgers, SL, Silva, CG. Differentiation of epileptiform abnormalities from normal transients and artifacts on ambulatory cassette EEG. American Journal of EEG Technology. 1983 Jun 1;23(2):113–25.10.1080/00029238.1983.11080105CrossRefGoogle Scholar
Shibasaki, H, Kuroiwa, Y. Electroencephalographic correlates of myoclonus. Electroencephalography and Clinical Neurophysiology. 1975 Nov 1;39(5):455–63.CrossRefGoogle ScholarPubMed
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