Pattern gallery

57 tracings: from the AES introductory text and atlas (St. Louis and Frey, 2016, Creative Commons) and from Jaime Shoup, MD, University of Louisville (used with permission). In quiz mode the caption is hidden until you tap the card: name the pattern first, then check.

57 shown

The 10-20 System electrode placements modified for neonates. Most of the neonatal EEG activity is found in the central regions of the brain, therefore the neonatal montage should have sufficient coverage of the centro-temporal regions.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 1 · Recording neonates and children →

Typical neonatal montage. Neonatal montages have some variations from institution to institution. The main variations are where the different channels are located. In this sample, the vertex electrodes are in the middle of the EEG trace, and the additional electrodes (EKG, respiratory belt, EMG, EOG) are placed at the bottom. Also this recording has EMG electrodes at the chin and limb. Displayed 10 seconds per screen or 30 mm/s.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 1 · Recording neonates and children →

Neonatal EEG artifacts from technician fixing electrodes. This sample shows some artifacts (channels 3, 4, 7, 8, 11, and 12) produced by fixing the electrodes.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Rhythmic artifacts of infancy and the ICU →

Patting artifact. This sample shows a widespread rhythmic artifact produced by patting the baby.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Rhythmic artifacts of infancy and the ICU →

Continuity of the neonatal EEG. Continuity in neonatal EEG refers to a trace with relatively steady amplitude. Discontinuity in neonatal EEG refers to periods of relatively higher amplitude or bursts that alternate with periods of lower amplitude or interbursts.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 6 · Continuity and the interburst interval →

Continuous neonatal EEG. Continuity in neonatal EEG refers to a trace with a steady amplitude. This sample shows a continuous EEG.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 6 · Continuity and the interburst interval →

Discontinuous neonatal EEG. Discontinuity in neonatal EEG refers to periods of relatively higher amplitude or bursts tha. t alternate with periods of lower amplitude or interbursts. This sample shows a normal 27-week CA infant with a discontinuous EEG, with interbursts seen in the first 3 seconds and in seconds 6 to 8 and 10. Bursts are seen in seconds 2 and 3 and second 9.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 6 · Continuity and the interburst interval →

Tracé alternant. This is a neonatal EEG sample of a 25-day-old girl born at 39 weeks GA. The sample shows a segment of quiet sleep with tracé alternant.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 6 · Sleep states at term →

Asymmetric background. This neonatal EEG sample was recorded in a 2-day-old full-term baby boy who had a left stroke. Notice the asymmetry in amplitude and frequency seen in the electrodes covering the left hemisphere (oval). This was an intermittent but consistent finding during the entire EEG record.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 7 · Grading the background in ACNS terms →

Neonatal EEG synchrony: example of encoches frontales and anterior frontal dysrhythmia. This is a sample of quiet sleep in a 25-day-old baby girl born at 39 weeks GA. There are two synchronous graphoelements in this sample: anterior frontal dysrhythmia, bifrontal semi-rhythmic delta activity lasting a few seconds and encoches frontales, bifrontal, sharply contoured symmetrical and synchronous transients. Both are seen in all behavioral states but more prominently in the transition from active to quiet sleep.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 6 · Synchrony and the graphoelements of prematurity →

Neonatal EEG: asynchrony. This is a sample of an abnormal neonatal EEG from a 2-week-old baby born at 37 weeks having neonatal seizures as a result of hypoxic-ischemic encephalopathy and sepsis. Notice the asynchrony of the bursts. The EEG is also significant for very low amplitude of the interburst periods.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 7 · Grading the background in ACNS terms →

Low-amplitude neonatal EEG in hypoxic-ischemic encephalopathy. (a) Low-amplitude, sleep, newborn with hypoxia; (b) low-amplitude neonatal EEG: arousal, no change in stage. (a) and (b) correspond to an EEG sample of a full-term baby boy with severe hypoxic-ischemic encephalopathy. This sample is recorded during the sleep state and shows a very depressed and undifferentiated EEG with very limited mixture of frequencies.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 7 · Grading the background in ACNS terms →

Reactivity during arousal. This sample corresponds to a neonatal EEG of a full-term baby. Notice the reactivity of the EEG to arousal with a relative voltage attenuation (seconds 9–14) followed by continuous activity (second 15 until end of page).
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 6 · Sleep states at term →

Encoches frontales. This EEG sample shows a normal sharp transient, encoches frontales.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 6 · Synchrony and the graphoelements of prematurity →

Normal sharp transients, central region. This EEG sample shows normal sharp transients in the central region.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 6 · Synchrony and the graphoelements of prematurity →

Central delta brushes, right rhythmic temporal theta. This is an EEG sample of a 32-week CA baby during sleep. Notice the centrally located delta brushes (delta wave with superimposed alpha beta activity 8 to 20 Hz) and the right temporal theta (brief paroxysmal or independent theta activity in the temporal region that can be sharply contoured but lacks evolution or after-going slow wave).
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 6 · Synchrony and the graphoelements of prematurity →

Neonatal EEG: artifact. Sharp wave–like transients owing to artifact in T7.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Rhythmic artifacts of infancy and the ICU →

Positive temporal sharp wave. This EEG sample is from a 2-week-old baby, born at 37 weeks, who had neonatal seizures. The sample shows positive temporal sharp waves.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 7 · Grading the background in ACNS terms →

Pediatric EEG: 5- to 6-Hz PDR in an 11-month-old child.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · The posterior dominant rhythm from 3 months to 15 years →

Pediatric EEG: 6- to 7-Hz PDR in a 12-month-old child.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · The posterior dominant rhythm from 3 months to 15 years →

Pediatric EEG: normal 16-month-old waking EEG record, reaching 7- to 8-Hz PDR.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · The posterior dominant rhythm from 3 months to 15 years →

Pediatric EEG: eye closing in a 23-month-old boy playing “peek-a-boo,” demonstrating 7-Hz PDR.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · The posterior dominant rhythm from 3 months to 15 years →

Pediatric EEG: asynchronous spindles in a 16-month-old boy.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · Sleep architecture and the drowsy danger zone →

Frontal arousal in a 16-month-old boy.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · Sleep architecture and the drowsy danger zone →

Pediatric EEG: normal waking background in a 10-year-old girl, showing a 10-Hz alpha PDR.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · The posterior dominant rhythm from 3 months to 15 years →

Pediatric EEG: N2 (stage 2 NREM) sleep in an 8-year-old boy.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · Sleep architecture and the drowsy danger zone →

Pediatric EEG: buildup of slow wave frequencies during hyperventilation in a 7-year-old girl.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · Activation in children: hyperventilation and photic stimulation →

Pediatric EEG: build-up response becomes more prominent later during hyperventilation in the same 7-year-old girl as sho. wn in Figure 43.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · Activation in children: hyperventilation and photic stimulation →

Pediatric EEG: photic driving response at 10-Hz flash frequency in a 7-year-old girl.
St. Louis & Frey (eds), AES 2016; figure courtesy of Elia M. Pestana-Knight, MD, Cleveland Clinic Foundation · CC BY-NC-SA 4.0 · tap to enlarge

Module 4 · Activation in children: hyperventilation and photic stimulation →

Example of 14- and 6-Hz positive spikes in a 13-year-old girl. Note the 14-Hz positive spiky waveforms best appreciated over the posterior temporal and biposterior head regions, best seen in the third second.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 5 · The benign variants, by age →

EEG examples of NCSE. The EEG in both (a) and (b) are displayed in a longitudinal bipolar display montage with a sensiti. vity of 7 mm/mV. (a) EEG contains spike and slow wave epileptiform discharges that are rhythmic and rapid (3 Hz). (b) EEG also contains sharp and slow wave epileptiform discharges that are rhythmic but are repeating at a slower frequency than those shown in (a).
St. Louis & Frey (eds), AES 2016; figure courtesy of Lauren C. Frey, MD, University of Colorado · CC BY-NC-SA 4.0 · tap to enlarge

Module 10 · Status epilepticus: thresholds by duration and by burden →Module 11 · Why the ICU needs its own vocabulary →

Triphasic waves. Triphasic waves can have multiple different EEG presentations. The triphasic waves in (a) and (b) occur singly with variable maxima. The triphasic waves in (c) are more uniform and occur repetitively.
St. Louis & Frey (eds), AES 2016; figure courtesy of Lauren C. Frey, MD, University of Colorado · CC BY-NC-SA 4.0 · tap to enlarge

Module 11 · Naming the pattern: main terms and plus modifiers →

LPDs. Lateralizing periodic discharges over the right hemisphere.
St. Louis & Frey (eds), AES 2016; figure courtesy of Lauren C. Frey, MD, University of Colorado · CC BY-NC-SA 4.0 · tap to enlarge

Module 11 · Naming the pattern: main terms and plus modifiers →

GPDs. Generalized periodic discharges. Longitudinal bipolar montage.
St. Louis & Frey (eds), AES 2016; figure courtesy of Lauren C. Frey, MD, University of Colorado · CC BY-NC-SA 4.0 · tap to enlarge

Module 11 · Naming the pattern: main terms and plus modifiers →

Eye flutter evident in the frontopolar and anterior leads.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Physiologic artifacts: eyes, muscle, heart and skin →

Rapid eye movements generate small spike-like discharges in the frontopolar derivations.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Physiologic artifacts: eyes, muscle, heart and skin →

Glossokinetic potentials from tongue movement, reproducible by having the patient say “la, la.”.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Physiologic artifacts: eyes, muscle, heart and skin →

Dissimilar metals causing electrostatic artifacts during talking generate spiky waveforms in seconds 5 through 8 of this. epoch.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Non-physiologic artifacts: electrodes, lines and equipment →

Chewing artifact.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Physiologic artifacts: eyes, muscle, heart and skin →

Movement artifact mimicking a partial seizure discharge at the P3 electrode.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Non-physiologic artifacts: electrodes, lines and equipment →

Pulse artifact creates rhythmic slow wave artifact at F4. Note the frequency mirrors that of the cardiac cycle.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Physiologic artifacts: eyes, muscle, heart and skin →

Electrode “pop” artifact at P7 simulates rhythmic seizure activity.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Non-physiologic artifacts: electrodes, lines and equipment →

Electrode “pop” artifact at F3.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Non-physiologic artifacts: electrodes, lines and equipment →

Sweat artifact.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Module 3 · Physiologic artifacts: eyes, muscle, heart and skin →

Electrocerebral silence (brain death). Note the prominent cardiac cycle artifact, especially in O1, with the absence of any discernible cerebral activity.
St. Louis & Frey (eds), AES 2016 · CC BY-NC-SA 4.0 · tap to enlarge

Left hemispheric polymorphic delta slowing. Continuous, irregular delta activity over the left hemisphere (boxed), with a better organized right hemisphere. ECG channel at the bottom.
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 8 · Slowing: focal and diffuse →

Focal slowing of the left hemisphere. The left side is slower and less organized, with polymorphic theta to delta activity and a poorly sustained posterior rhythm; the right side is well organized, with alpha activity over the posterior regions (lecturer's annotations).
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 8 · Slowing: focal and diffuse →

Mild generalized slowing. Slow, poorly sustained posterior dominant rhythm, poor anterior-to-posterior gradient, and excess theta admixed with the alpha (lecturer's annotations).
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 8 · Slowing: focal and diffuse →

Moderate generalized slowing. Very slow posterior dominant rhythm, no anterior-to-posterior gradient, minimal variability, and diffuse theta and delta activity (lecturer's annotations).
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 8 · Slowing: focal and diffuse →

Severe generalized slowing. Diffuse delta with no posterior dominant rhythm, no anterior-to-posterior gradient and no reactivity (lecturer's annotation).
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 8 · Slowing: focal and diffuse →

Frontal intermittent rhythmic delta activity (FIRDA). Bursts of rhythmic delta with a bifrontal maximum (arrows).
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 8 · Intermittent rhythmic delta, asymmetries and breach →

Occipital intermittent rhythmic delta activity (OIRDA). Runs of rhythmic delta over both occipital regions (boxed), a childhood pattern.
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 8 · Intermittent rhythmic delta, asymmetries and breach →

Temporal intermittent rhythmic delta activity (TIRDA). Left temporal rhythmic delta, most rhythmic anteriorly and becoming polymorphic as it moves posteriorly (lecturer's annotation).
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 8 · Intermittent rhythmic delta, asymmetries and breach →

Generalized attenuation. Very low amplitude activity in every channel at a 140 µV scale; the ECG channel is the only conspicuous signal.
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 11 · Why the ICU needs its own vocabulary →

Diffuse beta activity with ECG artifact. Transverse montage. Generalized fast activity of the kind seen with benzodiazepines, and a time-locked ECG artifact (lecturer's labels).
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 11 · Why the ICU needs its own vocabulary →

Burst suppression. Longitudinal bipolar montage. Bursts of mixed-frequency activity separated by suppressed intervals.
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 11 · Why the ICU needs its own vocabulary →

Alpha coma pattern (lecture example). Referential montage with widespread, monotonous alpha-range activity, shown in the lecture as an alpha coma pattern in a comatose patient.
Jaime Shoup, MD, University of Louisville; used with permission · Used with permission · tap to enlarge

Module 11 · Why the ICU needs its own vocabulary →

Sources: St. Louis EK, Frey LC, eds. Electroencephalography: An Introductory Text and Atlas of Normal and Abnormal Findings in Adults, Children, and Infants. American Epilepsy Society; 2016, CC BY-NC-SA 4.0; and Jaime Shoup, MD, University of Louisville, used with permission (not for further copying). Images resized and captions shortened; full credits in ATTRIBUTIONS.md. Figures the book marks with a separate copyright were not reproduced.