1. Department of Neurosurgery, USC Keck School of Medicine, University of Southern California, Los Angeles, California;
2. Department of Neurosurgery, Ernst-Moritz-Arndt University Greifswald, Germany;
3. Department of Neurosurgery, Barrow Neurological Institute, St. Joseph’s Hospital, Phoenix, Arizona; and
4. Department of Neurosurgery, Brigham and Women’s Hospital, Boston, Massachusetts