1. Headache Outpatient Clinic, Department of Neurology, Saint Andrew’s State General Hospital of Patras, Greece
2. 1st Department of Neurology, Aeginition Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece
3. Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
4. Department of Neurosurgery, University Hospital of Patras, Rion-Patras, Greece