The migraine-cluster headache syndrome is defined as headaches that are predominately of one type but with at least one major timing factor plus three lesser features of the other or five lesser features of the other (no more than one of the opposing features is a weak differential feature). The most important factors distinguishing migraine (M) from cluster headache (CH) are the timing of attacks (random occurrence versus clustering, frequency, duration, hour of onset) and the prodromal phenomena which occur with classical M, but are rarely seen with CH. Somewhat less significant differentiating characteristics are the associated symptoms of ipsilateral eye redness and tearing, nasal congestion and secretion, and partial Horner's syndrome which often accompany CH, in contrast to the symptoms of nausea and vomiting commonly associated with M. Also helpful in establishing the diagnosis are the quality, site and recurrent laterality of the pain, as well as its aggravating and ameliorating factors. Weak features in the differential diagnosis of M and CH are age of onset, sex, family history, and response to therapy.
Patients with M or CH seen at the Headache Unit of Montefiore Medical Center during the past two years were evaluated for the occurrence of the migraine-cluster headache syndrome. Nine (1.0%) of 923 patients with M had 4 or more features of CH and 5 (3.2%) of 154 patients with CH had 4 or 5 characteristics of M. In 4 patients symptoms of M and CH were blended in such a way neither headache predominated.