Coexistence of contralateral cluster headache and probable paroxysmal hemicrania: a case report.

There is a clear overlap in clinical diagnosis between cluster headache (CH) and paroxysmal hemicrania (PH) and similarities are somewhat greater than differences. The originality of this report is the coexistence of contralateral TACs in the same patients at the same moment. According neuroimaging studies, CH hypothalamic activation occurs ipsilateral to the side of the headache while in PH hypothalamic activation occurs contralateral to the side of headache. It could be suggested that a continuous hypothalamic activation give a maladaptive plasticity recruiting closed neuronal aggregates responsible for the developing of PH after a long period of CH, confirming the central origin of both CH and PH. Further studies need to confirm this hypothesis.