EEG ICU and Continuous EEG Monitoring 2

Question 1

Generalized periodic discharges (GPDs) are most classically associated with which condition?

Accepted Answer

Creutzfeldt-Jakob disease (CJD)

Answer

GPDs (formerly called generalized PLEDs or BiPLEDs) with a triphasic morphology are classically associated with CJD, though they also appear in metabolic encephalopathies.

Question 2

Triphasic waves on EEG in an ICU patient most commonly indicate:

Accepted Answer

Toxic-metabolic encephalopathy such as hepatic or uremic encephalopathy

Answer

Triphasic waves — broad, anteriorly dominant GPDs with three phases — are a classic EEG marker of metabolic encephalopathy, particularly hepatic or uremic encephalopathy.

Question 3

Electrocerebral silence (ECS) on EEG, required for brain death determination, must be recorded at a sensitivity of:

Accepted Answer

2 µV/mm for 30 minutes with inter-electrode distances ≥10 cm

Answer

ACNS guidelines for EEG confirmation of brain death require recording at ≥2 µV/mm sensitivity for at least 30 minutes, using electrodes ≥10 cm apart, with no reactivity.

Question 4

In the ACNS ICU EEG terminology, the '+F' modifier on a periodic discharge pattern indicates:

Accepted Answer

Superimposed fast activity on the discharge

Answer

The '+F' modifier in ACNS standardized terminology denotes the presence of superimposed fast (beta-range) activity riding on top of the periodic or rhythmic discharge.

Question 5

A cEEG monitoring technologist notices sudden onset of rhythmic, evolving 2 Hz sharp-wave activity for 90 seconds followed by postictal slowing. This is best classified as:

Accepted Answer

Electrographic seizure

Answer

An electrographic seizure requires evolution in frequency, morphology, or spatial distribution lasting ≥10 seconds, and this pattern with evolution and postictal slowing meets criteria.

EEG - Electroencephalography Practice Test

EEG - Electroencephalography Practice Test

EEG ICU and Continuous EEG Monitoring 2