Greater occipital nerve as target for refractory chronic headaches. from corticosteroid block to invasive neurostimulation and back

Headache disorders are one of the major causes of disability worldwide, recently classified as the third cause by the Global Burden of Disease 2010 [1]. Their chronic form and refractory headaches are to be considered important challenges in the daily management of a third-level headache center. The pyramidal progression toward structures characterized by more and more complex and multidisciplinary competences is a given fact based on the research of innovative solutions and multimodal approaches. The clinical definition of the most relevant forms of chronic headaches not responding to conventional therapies is best figured in refractory chronic headaches (rCHs), more precisely refractory chronic cluster headache (rCCH) and refractory chronic migraine (rCM) complicated by acute drug overuse. The European Headache Federation (EHF) has defined the clinical concept of refractoriness in two separate consensus papers, one for rCM [2] and the other for rCCH.