Where migraine-like or other headache and epilepsy are both part of a specific brain disorder (eg, MELAS), the headache is coded to that disorder. Where a seizure occurs during or immediately following a migraine aura, it is coded as 1.4.4 Migraine aura-triggered seizure.
Headache caused by an epileptic seizure, occurring during and/or after the seizure and remitting spontaneously within hours or up to 3 days.
- Any headache fulfilling criterion C
- The patient is having or has recently had an epileptic seizure
- Evidence of causation demonstrated by both of the following:
- headache has developed simultaneously with or soon after onset of the seizure
- headache has resolved spontaneously after the seizure has terminated
- Not better accounted for by another ICHD-3 diagnosis.
Well-documented reports support recognition of the subtypes 7.6.1 Ictal epileptic headache and 7.6.2 Post-ictal headache, according to their temporal association with the epileptic seizure.
Pre-ictal headache has also been described. In a small study of 11 patients with intractable focal epilepsy, frontotemporal headache was, ipsilateral to the focus in nine patients with temporal lobe epilepsy (TLE) and contralateral in one with TLE and one with frontal lobe epilepsy. More studies are needed to establish the existence of pre-ictal headache, and determine its prevalence and clinical features, in patients with partial and generalized epilepsy. Pre-ictal headache must also be distinguished from 1.4.4 Migraine aura-triggered seizure.