Treatment of the Patient with Refractory Headache.

PURPOSE OF REVIEW: To review recent studies outlining the management of refractory primary headache patients, including emerging therapies such as neuromodulation. This includes both noninvasive and invasive neuromodulation techniques. Recent studies on the management of medication overuse headache were also reviewed. RECENT
FINDINGS: There is no consensus as yet on the definitions of refractory chronic migraine and chronic cluster headache although there is broad agreement on some aspects of these terms. The importance of identifying medication overuse headache and dealing effectively with it has been highlighted in several studies although there is still not consensus on how best to achieve the cessation of medication overuse. Some recommend the use of preventative medication together with medication cessation, while others do not. Recent studies on neuromodulation have used both noninvasive vagal nerve stimulation as well invasive techniques. Recent studies using noninvasive vagal nerve stimulation for chronic migraine have been disappointing although the data in chronic cluster headache are more encouraging. Similarly, recent studies on occipital nerve stimulation have again been more positive in chronic cluster headache and generally negative in chronic migraine. In recent years, new forms of neuromodulation have emerged and long-term follow-up data from previous invasive neuromodulation techniques have become available. The sphenopalatine ganglion has been increasingly targeted by various interventions in several different headache types. Sphenopalatine ganglion stimulation is yielding encouraging data for the treatment of chronic cluster headache. New studies and long-term follow-up data from previous studies have provided further evidence for the benefit of deep brain stimulation for refractory chronic cluster headache although the exact target location is still debated. Data from phase 3 trials using CGRP monoclonal antibodies in chronic migraine and chronic cluster headache, if positive, may herald a long overdue, new and effective treatment for our refractory headache patients.