1. Department of Neurosurgery, Mayo Clinic, Jacksonville, Florida
2. Department of Neurosurgery, University of Buffalo Medical Center, Buffalo, New York
3. Department of Surgery, Division of Neurosurgery, University of Arizona, Tucson, Arizona (work was conducted while at the University of Buffalo Medical Center, Buffalo, New York)
4. Department of Neurosurgery, Mayo Clinic, Rochester, Minnesota
5. Department of Neurosurgery, Rush University Medical Center, Chicago, Illinois
6. Department of Neurosurgery, University of Texas Southwestern Medical Center, Dallas, Texas
7. Department of Neurosurgery, Albany Medical Center, Albany, New York
8. Department of Neurosurgery, University of Cincinnati Medical Center, Cincinnati, Ohio
9. Lyerly Neurosurgery, Baptist Health, Jacksonville, Florida