1. Department of Neurosurgery, University of Florida, Gainesville, Florida
2. Department of Neurosurgery, Vanderbilt University, Nashville, Tennessee
3. Department of Neurosurgery, Virginia Commonwealth University, Richmond, Virginia
4. Departments of Neurosurgery and Radiology, Stony Brook University Medical Center, Stony Brook, New York
5. Department of Neurosurgery, University at Buffalo, Buffalo, New York
6. Departments of Neurosurgery and Radiology, Medical University of South Carolina, Charleston, South Carolina
7. Department of Neurosurgery, Barrow Neurological Institute, Phoenix, Arizona