1. Department of Neurosurgery, Washington University, School of Medicine, St. Louis, Missouri
2. Department of Neurosurgery, Uniformed Services University of the Health Sciences National Naval Medical Center Bethesda, Maryland
3. Department of Radiology, Washington University, School of Medicine, St. Louis, Missouri
4. Department of Radiology and Washington University, School of Medicine, St. Louis, Missouri
5. Departments of Radiology and Chemistry, Washington University, School of Medicine, St. Louis, Missouri The Alvin J. Siteman Cancer Center