Brief paroxysmal head pain, with stabbing quality, describing a linear or zig-zag trajectory across the surface of one hemicranium.
A. Recurrent stabbing head pain attacks lasting 1-10 sec, fulfilling criterion B
B. The pain is felt to move across the surface of one hemicranium in a linear or zig-zag trajectory, commencing and terminating in the territories of different nerves
C. Not better accounted for by another ICHD-3 diagnosis.
A structural lesion must be excluded by history, physical examination and, when appropriate, investigation.
Patients with A4.11 Epicrania fugax describe their painful experience in terms of the trajectory of the pain between two distant points on the head surface, with motion from onset to termination taking just a few seconds. Such dynamic topography is a distinctive attribute that differentiates A4.11 Epicrania fugax from other epicranial headaches and neuralgias. The onset and termination points remain constant in each patient, with the pain strictly unilateral, although some patients have shifting sides. The pain usually moves forward, but backward radiation is also possible. Forward-moving pain starts in a posterior hemicranial area and tends to reach the ipsilateral eye or nose. Backward-moving pain starts in a frontal or periorbital area and tends to reach the occipital region. At the end of the attacks, ipsilateral autonomic signs such as lacrimation, conjunctival injection and/or rhinorrhoea may occur.
Although the attacks are mostly spontaneous, they may occasionally be triggered by touch on the point of onset, which may remain tender in between attacks.