1. Department of Neurosurgery, University Medical Center Hamburg-Eppendorf , Hamburg , Germany
2. Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School , Boston, MA , United States
3. Department of Neurosurgery, University Hospital Tübingen, Eberhard-Karls-University Tübingen , Tübingen , Germany
4. Department of Neurosurgery, University of Pittsburgh Medical Center , Pittsburgh, PA , United States
5. Department of Neurosurgery, University of Virginia Health System , Charlottesville, VA , United States
6. Department of Neurosurgery, Johannes Wesling Hospital Minden, Ruhr-University Bochum , Minden , Germany
7. Department of Neurosurgery, Federal Center of Neurosurgery , Novosibirsk , Russia
8. Department of Neurosurgery, Novosibirsk State Medical University , Novosibirsk , Russia
9. Department of Neurosurgery, University Medicine Greifswald , Greifswald , Germany
10. Department of Neurosurgery and Gamma Knife Radiosurgery, I.R.C.C.S. San Raffaele Scientific Institute, Vita-Salute University , Milan , Italy
11. Department of Neurosurgery, Helios Kliniken , Erfurt , Germany
12. Department of Neurosurgery, Clinical Neurosciences Center, University of Utah , Salt Lake City, UT , United States
13. Department of Neurosurgery, Hospital de Clínicas de Porto Alegre , Porto Alegre, Rio Grande do Sul , Brazil