1. Department of Neurosurgery, Stanford University, Stanford, California;
2. Department of Neurosurgery, Cabrini and Austin Health, Melbourne, Victoria, Australia;
3. Department of Neurosurgery, Charité—Universitätsmedizin, Berlin, Germany;
4. Division of Neurosurgery, Gaffrée e Guinle University Hospital, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro, Brazil;
5. Department of Neurology and Neurosurgery, McGill University, Montréal, Québec, Canada;
6. Department of Neurosurgery, Cleveland Clinic, Cleveland, Ohio;
7. Department of Neurosurgery, University of California, San Francisco, California;
8. Department of Neurosurgery & Neurorestoration, Klinikum Klagenfurt, Austria;
9. Department of Neurosurgery, University of Utah, Salt Lake City, Utah;
10. Department of Clinical Neurosciences and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Alberta, Canada;
11. Department of Neurosurgery, Leiden University Medical Center, Leiden, The Netherlands;
12. Department of Neurosurgery, Walter Reed National Military Medical Center, Bethesda, Maryland;
13. Department of Neurosurgery, University of Belgrade, Serbia;
14. Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri;
15. Department of Neurosurgery, Penn State Hershey Medical Center, Hershey, Pennsylvania;
16. Department of Neurosurgery, The American British Cowdray Medical Center, Mexico City, Mexico;
17. Department of Neurosurgery, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel;
18. Department of Neurosurgery, Duke University, Durham, North Carolina;
19. Department of Neurosurgery, Hospital de Clínicas, University of Buenos Aires School of Medicine, Buenos Aires, Argentina;
20. Department of Neurosurgery, Mayo Clinic, Rochester, Minnesota; and
21. Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania