Migraine with Isolated Facial Pain: A Diagnostic Challenge

It has long been recognized that the pain associated with migraine headache may wander outside the conventional calvarial boundaries of the head. This nuance has been lost on many practitioners and is often the basis of misdiagnosis when it comes to migraine headache.

In this issue of Cephalalgia, Obermann and colleagues report on a series of seven patients with ICHD-defined migraine without aura, all of whom had been misdiagnosed because of the atypical distribution of their pain (2). All presented with pain isolated to the second (V2) and/or third (V3) division of the trigeminal nerve. Five patients had been diagnosed with trigeminal neuralgia, one with paroxysmal hemicrania, and one with atypical migraine. All patients reported significant relief with triptans and each of three patients who were treated with preventive medication experienced a significant reduction in attack frequency. Ironically, the study was conceived by one of the authors who had misdiagnosed his own migraine as odontalgia because the pain associated with his attacks was isolated to V3. As the authors acknowledge and reference, ‘lower-half facial migraine’ is becoming recognized in rhinology and dental clinics and it is important for clinicians evaluating patients with facial pain to be alert to and on the look-out for the associated symptoms of migraine, so as to avoid unnecessary treatments and surgical procedures and, of course, deliver appropriate medical therapy.

While ‘facial’ pain in migraine sufferers might appear as a rare intellectual curiosity, the phenomenon is likely to be more widespread and has broad clinical implications. In a large population-based study, less than half with ICHD-defined migraine received the correct diagnosis, and within this group, 42% received the erroneous diagnosis of sinus headache (3). While there are probably several reasons for this, pain location is a prominent reason. In a study of 2294 patients presenting to primary care clinics across North America (4), 88% of patients with self- or physician-diagnosed sinus headache had migraine, while in the SAMS study, 86% of 100 patients with a self- or physician-diagnosis of sinus headache were found to have one or more subtypes of migraine (5). In the latter study, the most common reason (98%) for misdiagnosis was the location of the pain in the face or over the frontal or maxillary sinuses. Eighty per cent and 3.2% described pain in a V2 or V3 distribution, respectively, during migraine attacks, while 1.6% described their migraine pain as being isolated to V2 (5).

Inherent in these studies is a selection bias, as patients with self- or physician-diagnosed sinus headache were selected for evaluation. However, in two recent, large, randomized, placebo-controlled early intervention acute clinical trials, sinus pain/pressure was present in 43% of 4113 attacks of migraine in 1266 subjects (6). Sinus pain/pressure was more common than nausea and vomiting during attacks of migraine, even while pain intensity was still mild, and importantly, responded significantly to the combination of a triptan/NSAID compared with placebo (6).

Facial pain appears to be a common symptom during migraine attacks and while unusual, may be isolated to V2 and/or V3 and not accompanied by headache in a important minority of patients. As the patients in the SAMS study had been seen by an average of more than four physicians, and continued to be diagnosed with sinus headache (5), it is important for this information to be brought to the attention of those clinicians who routinely care for patients with headache and facial pain.