1. Texas Tech University Health Sciences Center, Lubbock, Texas
2. Department of Radiology and Imaging Sciences, National Institutes of Health, Bethesda, Maryland
3. Surgical Neurology Branch, NINDS, National Institutes of Health, Bethesda, Maryland
4. Neurosurgery Unit for Pituitary and Inheritable Diseases, Surgical Neurology Branch, NINDS, National Institutes of Health, Bethesda, Maryland