EEG Pediatric and Neonatal EEG 4 — Questions and Answers
Question 1: Which EEG pattern in a neonate is characterized by high-amplitude bursts separated by periods of relative quiescence and is considered normal in premature infants?
- Hypsarrhythmia
- Trace alternant (Correct answer)
- Burst suppression
- Delta brushes
Correct answer: Trace alternant
Trace alternant is a normal sleep pattern in term and preterm neonates consisting of high-amplitude bursts alternating with lower-amplitude inter-burst intervals.
Question 2: What is the most appropriate low-frequency filter setting when recording neonatal EEG to capture slow cerebral activity?
- 1 Hz (Correct answer)
- 5 Hz
- 10 Hz
- 30 Hz
Correct answer: 1 Hz
A low-frequency filter of 1 Hz (or lower) is used in neonatal EEG to preserve slow background activity that is characteristic of the immature brain.
Question 3: In a term neonate, which finding on EEG is most consistent with hypoxic-ischemic encephalopathy (HIE)?
- Continuous high-amplitude delta activity
- Burst suppression with prolonged inter-burst intervals (Correct answer)
- Abundant sleep spindles
- Well-organized trace alternant
Correct answer: Burst suppression with prolonged inter-burst intervals
Burst suppression with prolonged inter-burst intervals (>10 seconds) in a term neonate is a marker of severe cerebral dysfunction associated with HIE.
Question 4: Positive rolandic sharp waves (PRSW) in neonatal EEG are most strongly associated with which condition?
- Benign neonatal convulsions
- Periventricular leukomalacia (Correct answer)
- Hypocalcemia
- Pyridoxine dependency
Correct answer: Periventricular leukomalacia
Positive rolandic sharp waves are a reliable marker of periventricular white matter injury, particularly periventricular leukomalacia, in preterm neonates.
Question 5: Which behavioral state in neonates is associated with continuous low-to-moderate amplitude mixed-frequency EEG activity?
- Quiet sleep (NREM)
- Active sleep (REM) (Correct answer)
- Awake crying state
- Deep quiet sleep
Correct answer: Active sleep (REM)
Active (REM) sleep in neonates is characterized by continuous, relatively low-amplitude mixed-frequency activity similar to wakefulness.
Question 6: In pediatric EEG, the posterior dominant rhythm (PDR) reaches its adult frequency of approximately 10 Hz by what age?
- 1 year
- 3 years
- 8–10 years (Correct answer)
- 15 years
Correct answer: 8–10 years
The posterior dominant rhythm gradually increases from about 3.5 Hz at 3 months to the adult alpha frequency of ~10 Hz by 8–10 years of age.
Question 7: A 6-month-old presents with infantile spasms. Which EEG pattern is the hallmark of West syndrome?
- CSWS (continuous spike-wave during slow-wave sleep)
- 3 Hz spike-and-wave complexes
- Hypsarrhythmia (Correct answer)
- Focal temporal spikes
Correct answer: Hypsarrhythmia
Hypsarrhythmia — a chaotic, high-amplitude, disorganized pattern of multifocal spikes and slow waves — is the classic interictal EEG finding in West syndrome.
EEG Pediatric and Neonatal EEG 4
Which EEG pattern in a neonate is characterized by high-amplitude bursts separated by periods of relative quiescence and is considered normal in premature infants?