Reflex seizures and epileptic syndromes

Question 1

Idiopathic photosensitive occipital lobe epilepsy (IPOE)

Answer 1

Occipital seizures precipitated by photic stimuli are induced by video games and less often by television or other photic stimuli (reached epidemic proportions in Japan among children watching the cartoon Pokémon).

These reflex seizures contain all the elements in the spontaneous seizures of occipital lobe epilepsy, visual hallucinations, blurring of vision or blindness, alone or in combination. Less often, deviation of the eyes and head, eyelid fluttering and orbital pain.

EEG - By definition, all these patients are photosensitive and IPS elicits abnormal EEG paroxysms of spikes or polyspikes, which may be entirely confined to the occipital regions, or PPRs of GSWD.

Question 2

Jeavons syndrome (eyelid myoclonia with absence)

Answer 2

Eyelid myoclonia, not the absences, is the hallmark of Jeavons syndrome.

The seizures are brief (3–6 s), and occur mainly after eye closure and consistently many times a day . All patients are photosensitive.

GTCS can occur.

EEG - Frequent high-amplitude 3–6 Hz GSWD of mainly polyspikes.

Question 3

Primary (idiopathic) reading epilepsy

Answer 3

It is complex reflex epilepsy.

Seizures are elicited by reading and consist of brief myoclonic jerks mainly restricted to the masticatory, oral and perioral muscles.

If the patient continues reading despite jaw jerks, these may become more violent, spread to the trunk and limb muscles or generate other seizure manifestations before a GTCS develops.

Patient will rarely have more than one or two GTCS as they learn to stop when the symptoms start.

Hand myoclonic jerking is common among those with seizures precipitated by writing (graphogenic epilepsy).

EEG- Often inconspicuous because of jaw muscle artifacts.

Commonly, they consist of bilateral sharp waves in the temporo parietal regions with left-sided emphasis.