1. Department of Neurosurgery, Yale University, New Haven, Connecticut, USA;
2. Department of Neuroradiology, University Medical Center Göttingen, Göttingen, Germany;
3. Department of Neurology and Neurosurgery, Medical University of South Carolina, Charleston, South Carolina, USA;
4. Department of Neurosurgery, Thomas Jefferson University, Philadelphia, Pennsylvania, USA;
5. Department of Neurology, Chonnam National University Medical School, Chonnam National University Hospital, Gwangju, Korea;
6. Department of Neurosurgery, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA;
7. Department of Neuroradiology, West Virginia School of Medicine, Morgantown, West Virginia, USA;
8. Department of Neurosurgery, University of Miami Health System, Miami, Florida, USA;
9. Department of Diagnostic and Interventional Neuroradiology, University of Basel, Basel, Switzerland;
10. Department of Neurology, The University of Iowa, Iowa City, Iowa, USA;
11. Department of Neurosurgery, Semmes-Murphey Neurologic and Spine Clinic, University of Tennessee Health Science Center, Memphis, Tennessee, USA;
12. Department of Neurosurgery, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan;
13. Department of Neurosurgery, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA;
14. Department of Neurosurgery, Emory University, Atlanta, Georgia, USA;
15. Department of Radiology, Aou S. Giovanni di Dio e Ruggi d'Aragona, Salerno, Italy;
16. Department of Neurosurgery, Baylor College of Medicine, Houston, Texas, USA;
17. Department of Neurosurgery, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA;
18. Department of Neuroradiology, Centro Hospitalar Universitario de Lisboa Central, Lisbon, Portugal;
19. Department of Neurosurgery, University of Florida, Gainesville, Florida, USA;
20. Department of Neurosurgery, Washington University, St. Louis, Missouri, USA;
21. Department of Neurosurgery, Medica Uruguaya, Montevideo, Uruguay;
22. Department of Neurosurgery, University of Virginia, Charlottesville, Virginia, USA;
23. Department of Neurosurgery, University of Washington, Seattle, Washington, USA;
24. Department of Radiology, Mayo Clinic in Minnesota, Rochester, Minnesota, USA;
25. Department of Interventional Neuroradiology, Washington Regional Medical Center, Fayetteville, Arkansas, USA;
26. Department of Neurosurgery, University of Arizona, Tucson, Arizona, USA;
27. Department of Neurosurgery, Allegheny Hospital, Pittsburgh, Pennsylvania, USA;
28. Department of Interventional and Diagnostic Neuroradiology, Hospital Universitario La Paz, Madrid, Spain;
29. Department of Neurosurgery, University of Texas Medical Branch, Galveston, Texas, USA;
30. Department of Neurology, Yale University, New Haven, Connecticut, USA