Abstract
Dear Sir,
We read with interest the letter by Parisi et al. (1) on the “Ictal Epileptic Headache” (IEH) and we believe that it stimulates a further discussion on the topic, implying suggestions for the new classifications of both headache and epilepsy.
As stated by Parisi et al. (1), “ictal epileptic headache” (which could also be called simply “epileptic headache”) is a real although rare condition, in which headache is the sole or largely predominant symptom, and regarding which not more than 11 well-documented cases have been published (2).
We agree with the proposal by Parisi et al. (1) of an inclusion of this situation in a classification of headache linked to seizures. We suggest, however, some modifications to their proposal.
The first one concerns the criterion C: The necessity of a seizure pattern on the electroencephalography (EEG) concomitant with headache is inherent in the concept of “epileptic headache.” However, at least two cases have been reported (3,4) in which the scalp EEG was silent and epileptic abnormalities were detected only with deep electrode (case two (3)) or deep/stereo-EEG (case one (4)). Therefore we suggest modifying the text to “…discharges on scalp or deep EEG concomitantly with headache.”
Moreover, we do not think criteria B and D are necessary.
Concerning D, we think the response to treatment cannot be a criterion, since a seizure could not respond to antiepileptic treatment.
Concerning B, Parisi et al. (1) probably added this definition to differentiate it from the “Hemicrania epileptica” (7.6.1 of the International Classification of Headache Disorders-II (ICHD-2) classification). “Hemicrania epileptica,” however, is a condition that we think needs further discussion. In the literature we found that only Isler et al. (5) reported this condition. No further reports have been published in about 25 years, raising some suspicion as to its existence.
Moreover, if we simply eliminate from the definition of “Hemicrania epileptica” the term “partial” inserted in the criterion B (“…partial epileptic seizure”) and “ipsilateral” inserted in the criterion C (“…it is ipsilateral to the ictal discharge”), we obtain a definition that fits perfectly with that of “epileptic headache” or “ictal epileptic headache.”
Therefore, we suggest that “Hemicrania epileptica” be substituted by “Epileptic headache” or “Ictal epileptic headache” (the term “ictal” is not strictly necessary since an epileptic phenomenon is per se ictal).
IEH or epileptic headache is therefore a condition of head pain lasting seconds or minutes or hours (“status epilepticus”), with various locations and without other manifestations, with EEG (scalp or deep) abnormalities of various type, strictly contemporary to pain (onset and cessation contemporary to head pain). Lesions causing this can be located in different brain areas (2), or there may be no visible lesion. We could also differentiate the cases of IEH that may be followed by other epileptic manifestations (motor/sensory/autonomic) from “pure” IEH, characterized by only head pain, possibly with minor manifestations (2). In the same patient, in the course of the disorder, episodes of “pure” IEH may alternate with episodes followed by other epileptic manifestations.