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Professional Technical IVT

interictal

Pronunciation: in-ter-IK-tal

Occurring between seizures, referring to the period when a patient with epilepsy is not experiencing ictal activity.

Full Definition

Interictal describes the time period between seizures in patients with epilepsy, when there is no ongoing ictal activity. During interictal periods, patients typically return to their baseline neurological function, though some may experience postictal effects from previous seizures. Interictal EEG recordings may show epileptiform discharges such as spikes or sharp waves, which help confirm the diagnosis of epilepsy and localise seizure foci. Interictal phenomena can include behavioural changes, cognitive fluctuations, or persistent neurological deficits related to the underlying epilepsy syndrome or structural brain abnormalities.

Usage

Usage note: Commonly used in EEG reporting and epilepsy documentation to distinguish from ictal findings.

In Context

  • "Interictal EEG demonstrated frequent sharp waves over the left temporal region." — Electroencephalography report
  • "The patient's interictal behaviour was completely normal despite frequent nocturnal seizures." — Epilepsy monitoring unit notes

Also known as

between seizures

Contrasted with

ictal postictal

Don't confuse with

preictal postictal

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