1. Department of Neurosurgery, Hospital of the University of Pennsylvania, Penn Medicine, Philadelphia, Pennsylvania, USA;
2. Department of Neurosurgery, Cooper University Health Care, Camden, New Jersey, USA;
3. Department of Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA;
4. Department of Neurosurgery, University of Washington, Seattle, Washington, USA;
5. Department of Neurosurgery, Baylor College of Medicine, Houston, Texas, USA;
6. Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA;
7. Division of Neurosurgery, Beth Israel Deaconess Medical Center, Harvard Teaching Hospital, Boston, Massachusetts, USA;
8. Department of Neurosurgery, University of Utah, Salt Lake City, Utah, USA;
9. Department of Cerebrovascular and Endovascular Surgery, Baptist Neurological Institute and Lyerly Neurosurgery, Jacksonville, Florida, USA;
10. Departments of Neurology and Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
11. Department of Neurosurgery, Emory University School of Medicine, Atlanta, Georgia, USA;
12. Department of Neurosurgery, NYU Langone Medical Center, New York, New York, USA;
13. Department of Neurosurgery, Medical University of South Carolina, Charleston, South Carolina, USA;
14. Department of Neurosurgery, University of California-San Diego, La Jolla, California, USA;
15. Department of Neurosurgery, University of Texas Medical Branch, Galveston, Texas, USA;