The growing landscape of ictal epileptic headache

To the Editor:

The term ictal epileptic headache (IEH) has been increasingly used in the last 10 years to define a headache as an isolated symptom of epileptic seizure, and it is now recognized in the International Classification of Headache Disorders 3rd edition criteria (coded 7.6.1).

Clinical depiction and electroencephalograms (EEG) in subjects with suspected IEH are mandatory to achieve a correct diagnosis (1). In most of these patients, headache does not show as unusual, and indeed resembles migraine with or without aura or tension-type headache in some cases (1). Of note, the ictal EEG shows abnormalities compatible with an epileptic origin that starts and ends in concomitance with the head pain.

In this issue, Taga and Florindo (2) report two patients with different paroxysmal headaches (i.e. glossopharyngeal neuralgia and SUNCT) associated with ictal epileptic discharge at the EEG.

As only few cases of short lasting ictal headaches of epileptic origin have been so far described, the present report is of great interest and raises some reflections:

it confirms that the diagnosis of IEH is probably under-recognized (1). In this report, the final diagnosis of the patient with glossopharyngeal neuralgia was a pharmacoresistant focal epilepsy due to left frontal polymicrogyria. Notably, a typical attack of SUNCT was followed by loss of consciousness and tongue biting, leading to the diagnosis of epileptic seizure in the other patient. According to the recent International League Against Epilepsy (ILAE) classification, an ictal painful attack must be recognized as a focal aware seizure of sensory type (3). In this sense, the report of Taga and Florindo (2) raises the question of whether an EEG recording should always be obtained in subjects with headache not responsive to conventional medical treatments.

Taga and Florindo (2) define as “ictal headache” the clinical picture of these two patients, closely resembling two paroxysmal primary headache disorders, with an EEG recording showing abnormalities indicative of epileptic origin. Indeed, the term “ictal headache” was used 30 years ago by Laplante (1) to define headache occurring as the sole manifestation of an epileptic seizure.

We encourage the use of IEH, as now recognized in the International Classification of Headache Disorders 3rd edition criteria (coded 7.6.1), instead of ictal headache for two reasons: i) when headache/pain of epileptic origin demonstrated by ictal EEG recording is an isolated event, the term “ictal” reinforces the concept of paroxysmal headache/pain as genuine seizure, and it defines the temporal concept; ii) when headache/pain is an isolated manifestation, it is mandatory to define the origin (i.e. epileptic), as an ictal headache may also be non-epileptic in origin.