Definition of the postictal state: when does it start and end?

Area of Science:

• Neurology
• Clinical Neurophysiology

Background:

• The postictal state, following an epileptic seizure, is difficult to define operationally.
• Complex partial seizures present challenges in distinguishing postictal impairments from seizure activity.
• Patient unawareness of seizures complicates the identification of postictal states.

Purpose of the Study:

• To explore the diagnostic ambiguities in defining the postictal state.
• To evaluate the utility of electroencephalography (EEG) in distinguishing ictal and postictal periods.
• To propose a more accurate method for describing seizure aftermath.

Main Methods:

• Review of clinical definitions and diagnostic criteria for postictal states.
• Analysis of electroencephalographic (EEG) findings in relation to behavioral changes.
• Comparison of scalp EEG and clinical observations during and after seizures.

Main Results:

• Operational definitions of the postictal state are often difficult to apply, particularly for complex partial seizures.
• EEG can show focal slowing during and after seizures, blurring the ictal-postictal boundary.
• Discrepancies exist between EEG epileptiform discharges and observed behavioral changes.

Conclusions:

• The distinction between ictal, postictal, and interictal states can be ambiguous.
• Interictal abnormalities may represent seizure fragments, further complicating definitions.
• A descriptive approach focusing on behavioral and EEG sequences is preferable to arbitrary stage labeling.