If, after assessing the patient, you feel the seizure was likely to be unprovoked, further investigations are required to help establish a diagnosis of epilepsy.

EEG

Ideally, carry out an EEG within 24-48 hours post seizure; this will reveal substantial abnormalities in 70% of cases, as it:

• Points to focal lesions, especially localised slow waves
• Predicts recurrence
• Indicates a specific epilepsy syndrome (spike pattern)

A sleep deprived EEG may detect epileptiform spikes in a further 13-31% cases with negative EEG.

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Interictal EEG

Normal EEG