Evidence for hypothalamic activation in cluster headache.

Abstract

P.J. Goadsby ( ) Institute of Neurology The National Hospital for Neurology and Neurosurgery Queen Square, London WC1N, United Kingdom Introduction Cluster headache is a clinically well-defined disorder in which patients suffer extremely painful headaches with clock-like regularity one to three times, or more, a day for perhaps several months, and usually followed by a period of remission [1]. Cluster headache has been recognised for at least 250 years [2], yet mechanistically it has remained a poorly understood condition until recent times. The three major aspects of the pathophysiology of cluster headache are: the trigeminal distribution of the pain, the autonomic features and, more important, the episodic pattern of the attacks, which are in many ways the defining clinical signature of the disorder compared to migraine [3]. These features raise the classic issues of the location of the lesion and the generic terminology that should be applied to these and related headaches, such as migraine. Ekbom and Greitz, in their classic observation of changes in the internal carotid artery during angiography of a patient suffering an acute cluster headache, suggested a pathological focus in the region of the cavernous sinus [4]. The arguments supporting a role of this locus in the disease have been set out elsewhere [5, 6]. Although both migraine and cluster headache are often referred to as “vascular headaches”, I would suggest that they should be referred to generically as “neurovascular headaches”. This proposal is partly based on the observation of brain stem activation during spontaneous migraine [7], and partly on studies of the trigeminovascular system [8], with more relevance to cluster headache, the proposal is based on the site of dysfunction in the central nervous system [9].