1. Department of Neurological Surgery, The Ohio State University Wexner Medical Center, Columbus, Ohio;
2. Surgical Neurology Branch and
3. Office of the Clinical Director, National Institute of Neurological Disorders and Stroke;
4. Neuroradiology Section, Diagnostic Radiology, Clinical Center at the National Institutes of Health;
5. Division of Epidemiology and Clinical Applications, National Eye Institute;
6. Urologic Oncology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland; and
7. Department of Neurological Surgery, University of Virginia Health Sciences Center, Charlottesville, Virginia