1. Mallinckrodt Institute of Radiology (D.C.L., M.S.G., A.P.K.), Washington University School of Medicine, St Louis, MO.
2. Department of Neurology (M.M.G., K.P.G., M.S.G., A.P.K.), Washington University School of Medicine, St Louis, MO.
3. Department of Pediatrics (K.P.G.), Washington University School of Medicine, St Louis, MO.
4. Department of Neuroscience (M.S.G.), Washington University School of Medicine, St Louis, MO.
5. Department of Neurology (C.A.-L.), University of Washington, Seattle.
6. Department of Radiology (D.K.H.), University of Washington, Seattle.
7. Department of Neurological Surgery (D.K.H.), University of Washington, Seattle.
8. Department of Neurological Surgery (A.P.K.), Washington University School of Medicine, St Louis, MO.