EEG & Periodic discharges test

What is the primary function of an EEG?

To detect electrical activity in the brain

Which of the following is a hallmark EEG feature of Lennox-Gastaut syndrome?

Slow 2-2.5 Hz spike-and-wave

Triphasic waves are most commonly associated with

Metabolic encephalopathy

Which EEG pattern is most characteristic of childhood absence epilepsy?

1-2 Hz slow spike-and-wave

What is the typical frequency of generalized periodic discharges (GPDs)?

1-2.5 Hz

Lateralized periodic discharges (LPDs) are most commonly associated with

Acute focal structural lesions

What EEG pattern is often seen in benign focal epilepsy of childhood?

Rolandic spikes

Which of the following is NOT a typical cause of bilateral independent periodic discharges (BIPDs)?

Migraine

What is the clinical significance of burst suppression on EEG?

It suggests severe brain dysfunction

Which EEG pattern is most commonly associated with myoclonic epilepsy?

Polyspike-and-wave bursts

What is the typical morphology of triphasic waves?

Three phases with a surface positive main phase

What is the most common EEG abnormality in post hypoxic encephalopathy

Generalized periodic discharges (GPDs)

What is the mortality rate associated with GPD in ICU patients, according to the study?

60%

Which of the following EEG findings is considered a benign variant?

Breach rhythm

What is the significance of interictal epileptiform discharges (IEDs)?

They indicate an epileptic focus

What EEG pattern is most commonly seen in herpes simplex encephalitis?

Lateralized periodic discharges (LPDs)

What is the typical EEG finding in autoimmune encephalitis?

GPD

What EEG pattern is associated with a high risk of seizures and poor prognosis in critically ill patients?

LPDs

What is the primary mechanism behind periodic discharges?

Disruption of thalamocortical circuits

Which EEG pattern is most likely to be seen in a patient with hepatic encephalopathy

Triphasic waves