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Advanced Technical IVT

Interictal Epileptiform Discharge

Also written as: IED — Interictal Epileptiform Discharge

Abnormal electrical activity recorded on EEG between seizures that suggests epileptic potential.

Full Definition

Interictal epileptiform discharges (IEDs) are distinctive EEG waveforms occurring between clinical seizures that indicate epileptic brain activity. These discharges include spikes, sharp waves, and spike-and-wave complexes that have specific morphological characteristics distinguishing them from normal brain rhythms. In pediatric neurology, IEDs help support epilepsy diagnosis, guide treatment decisions, and may predict seizure risk. However, their presence does not always correlate with clinical seizure frequency.

Usage

Usage note: Commonly abbreviated as IED in clinical documentation.

In Context

  • "The EEG showed frequent interictal epileptiform discharges over the right temporal region." — EEG interpretation report
  • "Increased interictal epileptiform discharge frequency may indicate need for medication adjustment." — Clinical monitoring note

Also known as

IED epileptiform activity

Contrasted with

normal EEG activity

Don't confuse with

artifact benign variant ictal discharge

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