Daily morning hemifacial spasm in a patient with cluster headache.

The article presents a case report about a man with a history of cluster headache, who had developed early morning hemifacial spasm. The hemifacial spasm without headache can be explained by a difference in the activation threshholds for trigeminal afferents and for facial motoneurons. The patient is diagnosed to have a subtype of the cluster headache syndrome.