1. Department of Neurological Surgery, University of Pittsburgh Medical Center;
2. University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania;
3. Departments of Neurological Surgery and
4. Radiation Oncology, University of California, San Francisco, California;
5. Department of Neurological Surgery, University of Manitoba Health Sciences Centre, Winnipeg, Manitoba; and
6. Department of Neurological Surgery, University of Virginia Health System, Charlottesville, Virginia;
7. Department of Neurological Surgery, Centre Hospitalier Universitaire de Sherbrooke, Quebec, Canada