[1] Harvard Medical School,Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center
[2] University of Copenhagen,Danish Headache Center, Department of Neurology, Rigshospitalet, Faculty of Health and Medical Sciences
[3] Department of Neurorehabilitation / Traumatic Brain Injury,BIDMC Comprehensive Headache Center, Departments of Neurology and Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center
[4] Rigshospitalet Glostrup,Department of Clinical Medicine, Faculty of Health and Medical Sciences
[5] Harvard Medical School,undefined
[6] University of Copenhagen,undefined