1. Department of Neurosurgery Medical Faculty and University Hospital Düsseldorf, Heinrich‐Heine‐Universität Düsseldorf Düsseldorf Germany
2. Department of Neurosurgery and Neurobiology Barrow Neurological Institute Phoenix AZ USA
3. Department of Neurosurgery, Stroke Center Sapporo Teishinkai Hospital Sapporo Hokkaido Japan
4. Department of Neurosurgery University of Helsinki and Helsinki University Hospital Helsinki Finland
5. Department of Neurological Surgery Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center Phoenix AZ USA