Epileptic seizures and headache/migraine: A review of types of association and terminology

PURPOSE There are different possible temporal associations between epileptic seizures and headache attacks which have given rise to unclear or controversial terminologies. The classification of the International League Against Epilepsy does not refer to this type of disorder, while the International Classification of Headache Disorders (ICHD-2) defines three kinds of association: (1) migraine-triggered seizure ("migralepsy"), (2) hemicrania epileptica, and (3) post-ictal headache. METHODS We performed an extensive review of the literature, not including "post-ictal" and "inter-ictal" headaches. RESULTS On the basis of well-documented reports, the following clinical entities may be identified: (A) "epileptic headache (EH)" or "ictal epileptic headache (IEH)": in this condition headache (with or without migrainous features) is an epileptic manifestation per se, with onset, and cessation if isolated, coinciding with the scalp or deep EEG pattern of an epileptic seizure. EH maybe followed by other epileptic manifestations (motor/sensory/autonomic); this condition should be differentiated from "pure" or "isolated" EH, in which headache/migraine is the sole epileptic manifestation (requiring differential diagnosis from other headache forms). "Hemicrania epileptica" (if confirmed) is a very rare variant of EH, characterized by ipsilateral location of headache and ictal EEG paroxysms. (B) "Pre-ictal migraine" and "pre-ictal headache": when a headache attack is followed during, or shortly after, by a typical epileptic seizure. The migraine attack may be with or without aura, and its seizure-triggering role ("migraine-triggered seizure") is still a subject of debate. A differentiation from occipital epilepsy is mandatory. The term "migralepsy" has not been used uniformly, and may therefore led to misinterpretation. CONCLUSIONS On the basis of this review we suggest definitions and a terminology which may become the basis of a forthcoming classification of headaches associated with epileptic seizures.