Migraine treatment with external trigeminal nerve stimulation: current knowledge on mechanisms.

s. In a pilot trial of 10 episodic migraine patients who treated 3 successive attacks with the device, total relief without rescue medication was obtained in 12% of attacks at 30 minutes, incomplete relief with rescue medication in 42.5% and no effect in 45.5% (28). In an open study of 16 patients, the Cefaly device was effective and welltolerated as rescue therapy for migraine attack symptoms present since at least 72 hours; it reduced the migraine headache on average by 46%, and 56% of patients declared they would like to use the device again (29). In another open study, Chou et al. (30) treated 30 patients during an attack in the hospital for 1 hour, which resulted on average in a 57% decrease of headache intensity. The sham-controlled trial with a similar protocol is about to be completed (see table 1). We recently published the results of an Internet survey on migraine attack treatment with the Cefaly in 463 regular users using a structured questionnaire: 88.6% of them reported using the device in 71.8% of their attacks; the use of the device allowed a reduction of acute medication intake in 42.6% of attacks (31). The precise mode of action of pericranial neurostimulation methods in migraine remains to be determined. Recent neuroimaging studies, however, may shed light on possible relevant mechanisms.