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Intermediate Technical IVT

electroencephalogram

Also written as: EEG — electroencephalogram

Recording of electrical activity in the brain used to diagnose seizure disorders and other neurological conditions.

Full Definition

An electroencephalogram (EEG) is a diagnostic test that measures and records electrical activity in the brain through electrodes placed on the scalp. In neurology practice, EEGs are primarily used to diagnose epilepsy, evaluate seizure disorders, and assess brain function in various neurological conditions. The test can be performed as a routine 20-30 minute recording, a prolonged ambulatory monitoring session, or continuous video-EEG monitoring in hospital settings. Abnormal findings include spike-and-wave patterns, focal slowing, and epileptiform discharges that help localize seizure foci and guide treatment decisions.

Usage

Usage note: The acronym EEG is more commonly used in clinical practice than the full term.

In Context

  • "The electroencephalogram revealed bilateral spike-and-wave complexes consistent with generalized epilepsy." — diagnostic report
  • "Continuous video-electroencephalogram monitoring captured three focal seizures originating from the left temporal lobe." — epilepsy monitoring unit report

Also known as

EEG brain wave test

Don't confuse with

electromyogram electrocardiogram

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