1. Neurosurgical Service, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts;
2. Department of Neurological Surgery, Ohio State University Wexner Medical Center, Columbus, Ohio;
3. University of Sydney Westmead Clinical School, Westmead, New South Wales, Australia;
4. Department of Neurosurgery, The National Neuroscience Institute, King Fahad Medical City, Riyadh, Saudi Arabia; and
5. Division of Neurosurgery, Hamilton General Hospital, McMaster University and Hamilton Health Sciences, Hamilton, Ontario, Canada