Epilepsy and headache can exist independently in the same patient or correlate in different ways. According to their temporal occurrence, headache in epileptic patients can be either interictal or peri-ictal. Headaches occurring between seizures, without a time-locked association, are called interictal headaches, whereas peri-ictal headaches are further classified as preictal, ictal and postictal, depending on the time they occur since the beginning of the seizure [4].

In accordance with the recently revised International Classification of Headache Disorders 3rd Edition (ICHD-3 2018) [5], there are three disorders correlating headache and epilepsy: migraine aura-triggered seizure, ictal epileptic headache and post-ictal headache. Migraine aura-triggered seizure is a seizure triggered by an attack of migraine with aura. Ictal Epileptic Headache (IEH) is caused by and occurs during a partial epileptic seizure, ipsilateral to the epileptic discharge and remits immediately or soon after the seizure has terminated, whereas post-ictal headache is caused by and occurs within three hours after an epileptic seizure, and remits spontaneously within 72 hours after seizure termination.

According to the ICHD-3rd edition [5], the aforementioned patient presented with a primary headache, since medical history, physical examination and imaging studies were normal. Specifically, she fulfilled the diagnostic criteria of a migraine disorder, considering that the recurrent headache attacks were lasting several hours, had unilateral location, moderate to severe intensity and were accompanied by photophobia and phonophobia.

A primary headache is diagnosed through comprehensive medical history and neurological examination [6]. If a specific cause, such as a brain tumor or epilepsy is suspected, the patient undergoes brain imaging or EEG, to differentiate it from a secondary headache. Although any physicians tend to perform EEGs in cephalalgic patients, it is not routinely indicated for headache diagnosis. American Academy of Neurology suggests EEG is not useful in the routine evaluation of patients with headache [2]. This does not exclude the use of EEG to evaluate headache patients with associated symptoms suggesting a seizure disorder such as atypical migrainous aura or episodic loss of consciousness [7]. Therefore, if a patient presents with a headache and features suggestive of an ictal origin, an EEG should be performed to rule out an underlying epileptic mechanism. Regarding our case, we assumed the numbness of the sculp and right arm could represent either an ictal or postictal phenomenon, especially an analog of Todd paresis. Therefore, an EEG recording was performed.

EEG abnormalities in migraine have been reported by a number of authors over the years and mostly include focal or diffuse slowing findings and abnormalities during activation procedures such as hyperventilation [8]. Epileptiform discharges are less commonly reported. Sethi et al. performed EEGs in 50 cephalalgic patients and found a total of 13 abnormal EEGs, of which 8 had nonepileptiform slowing, while epileptiform features were noted in 5 patients [3].

The presumably ictal phenotype of the female patient’s headache attacks is pointed out by the presence of the concurrent symptom of numbness, the EDs in the EEG and the sufficient clinical response to an anti-epileptic drug (lamotrigine) which is commonly not used for the prevention of migraine without aura [9]. Considering the aforementioned definitions according to ICHD-3rd edition [5], migraine aura-triggered seizure is not a possible diagnosis, since an epileptic seizure never takes place. Likewise, ictal epileptic headache could not be suggested, due to lack of an EEG recording during the headache attack [10]. However, if we assume that a subclinical epileptic seizure has occurred before, post-ictal headache could be a reasonable explanation. Lastly, a random coincidence between a migraine disorder and epileptiform discharges in the EEG can occur and simply represent this patient’s case.

In conclusion, when a patient presents with a resistant, drug-refractory headache or cephalalgic attacks suggestive of ictal origin, an EEG should be performed. Subsequently, if the EEG demonstrates epileptiform discharges and the headache presents with epileptic features, it could be reasonable to administer anti-epileptic medication. However, if the patient’s cephalalgic events do not imply an apparent ictal nature, it is prudent applying at first common anti-migraine medication and eventually, if no remission is accomplished, AEDs.