Hemicrania continua is an uncommon primary headache characterized by continuous, unilateral cranial pain of moderate intensity, more painful exacerbations with cranial autonomic features, and an absolute response to indomethacin. It is considered one of the trigeminal autonomic cephalalgias. Activation of the trigeminal–autonomic reflex and the contralateral posterior hypothalamic grey is thought to play an important role in its pathophysiology. The mean age of onset is in the third decade and there is a female preponderance of 2:1. Hemicrania continua can be divided into a remitting and an unremitting type; most patients suffer from the unremitting type. Any part of the head or neck can be affected, and pain is mainly described as throbbing. Many patients experience migrainous features during exacerbations. Physical and supplementary investigations are mostly normal. Other trigeminal autonomic cephalalgias and migraine are the main differential diagnostic alternatives for consideration.
Neuromodulatory Approaches to the Treatment of Trigeminal Autonomic Cephalalgias (TACs)
