The Current Means for Detection of Migraine Headache Trigger Sites

Abstract

The authors' 15-year experience with migraine surgery has led them to believe that the most common reasons for incomplete response are failure to detect all of the trigger sites or, on rare occasions, inadequate surgery on the trigger sites. Thus, accurate identification of trigger sites is essential. The purpose of this article is to share the authors' current stepwise algorithm for accurately detecting the migraine trigger sites, which has evolved through surgery on nearly 1000 patients. To begin, a thorough history is taken. Each patient's constellation of symptoms can point toward one or multiple trigger points. The patient is asked to point to the most frequent site from which migraine headaches originate with one fingertip, and then the site is explored with a Doppler. If an arterial Doppler signal is identified at the site, it is considered an active arterial trigger site. Response to a nerve block with a local anesthetic in a patient with an active migraine headache confirms the presence of a trigger site. If the patient does not have pain at the time of the office visit, an injection of botulinum toxin A at the suspected trigger site may be considered. Although positive responses to botulinum toxin A and nerve block are very helpful and reliable in confirming the trigger sites, negative responses must be interpreted with extreme caution. In patients with a migraine headache starting from the retrobulbar site, a computed tomography scan of the paranasal sinuses is obtained to look for contact points and other pathology that would confirm rhinogenic trigger sites.

Surgical Therapy of Migraine and Tension-Type Headache

“…This evidence was followed by a prospective study where he reported a 95% rate of either complete alleviation or improvement in MH after a mean follow-up of 1 year [5]. Over the last 15 years, Guyuron conducted several anatomical and clinical studies reporting a reduction of the frequency, duration, and intensity of MH by at least half in 80-90% of patients [4][5][6][7][8][9][10]. In 2011, Guyuron et al published a study examining the longterm benefits of migraine surgery where it was reported an 88% success rate after a 5-year follow-up (29% completely healed; 59% gained improvement; 12% did not show any change) [8].…”

“…MH characteristics (e.g., frequency, duration, and amount of drugs needed) also seem to affect the surgical outcome; milder MH have higher chances of improvement in comparison to more severe ones, which are more likely to recur postoperatively [5,8,9]. Preliminary Botox infiltration does not affect the surgical success [10].…”

“…The course of the nerve in the area of the superior nuchal line is variously described, because of the large anatomical variability that these structures present. According to some authors, the nerve arches medially to the semispinalis muscle, boring the fascial plane, while others describe it piercing the muscles themselves: the semispinalis in the vast majority of cases (90% of cases), the inferior oblique, or the trapezius [3,[5][6][7][8][9][10][11]. The latest studies have shown the exact location of the intramuscular course of the nerve: it is located 3 cm below and 1.5 cm lateral to the occipital protuberance [3,5].…”

“…Almost 90% of the patients can recognize more than one MH trigger site; the surgical deactivation may be performed at all sites during the same surgical procedure [10]. However, we routinely deactivate the main trigger site first, and then a second or third surgery is performed at the remaining sites 3 months after each surgery.…”

“…Essential step is detecting the precise site of pain onset [10]. Although patients may report diffuse headache, once they are asked to locate where the pain begins, they can precisely identify it by pointing with one fingertip, and that is where the surgical treatment must be focused on to release the nerve branch involved.…”