Epicrania Fugax

Abstract

Epicrania fugax (EF) is a primary headache of recent description. EF essentially consists of brief paroxysms of pain describing a linear or zigzag trajectory across the surface of one hemicranium, commencing and terminating in the territories of different nerves. The pain of forward EF originates in a particular area of the occipital, parietal or temporal regions and moves anteriorly, whereas the pain of backward EF originates in the frontal area, the eye or the nose and moves posteriorly. Some patients have ocular or nasal autonomic accompaniments, and some have triggers. Between attacks, many patients have continuous or intermittent pain and/or tenderness at the stemming area. Pain frequency is extremely variable and some patients have spontaneous remissions. Preventive therapy is required when the paroxysms are frequent and non-remitting. Neuromodulators, indomethacin, amitryptiline, nerve anesthetic blockades, and trochlear steroid injections have been used in different cases, with partial or complete response.

Epicrania fugax combining forward and backward paroxysms in the same patient: the first four cases

“…We have also observed in some cases an interictal pain in the area in which pain paroxysms end (data not published). Similarly as a nummular headache may be located in different scalp areas in the same patient,13 peripheral generators of EF may be located in anterior or posterior regions,12 as happened in three of our cases. In our opinion, therefore, it is not surprising to have the appearance of forward and backward radiations in the same patient as described in this series.…”

“…The etiology of EF remains unknown, although clinical characteristics such as stabbing character of the pain and the presence of a stemming area suggest an epicranial source 12. It has been proposed that the pain may start at the terminal branches of the pericranial nerves and that pain spreads due to different mechanisms, such as aberrant ephaptic transmission connecting different nerve fibers, involvement of transdiploic fibers,1 or recruitment of central mechanisms 12…”

“…It has been proposed that the pain may start at the terminal branches of the pericranial nerves and that pain spreads due to different mechanisms, such as aberrant ephaptic transmission connecting different nerve fibers, involvement of transdiploic fibers,1 or recruitment of central mechanisms 12…”

Cranial and Facial Epicrania Fugax: Combination of Both Clinical Pictures in the Same Patients

“…In 2008, Pareja et al first defined the cranial subtype as brief paroxysms of pain lasting 1‐10 seconds and moving through different nerve territories of one hemicranium with a linear or zigzag trajectory . Since then, different pain trajectories have been described: forward, backward, coronal, and even multidirectional . A facial variant has also been acknowledged, with the pain radiating through several dermatomes of the face in an upward or downward direction .…”

“…Moreover, patients with other “epicranial pain disorders” such as nummular headache may develop episodes of EF that radiate from the area where the nummular pain is localized. However, it seems reasonable to think of an implication of central pathways that justify the spread between different peripheral territories . Evidence of this hypothesis is the description of 3 cases of symptomatic EF in the literature: a skull base meningioma in contact with the trigeminal nerve root after radiotherapy, a lateral medullary infarction, and a cerebellar abscess after a surgical intervention for a Chiari type 1 malformation .…”