1. From the Stanford University School of Medicine, CA (S.C.D.C.)
2. Department of Medicine, Quantitative Sciences Unit (R.L.B., R.K.)
3. Stanford University School of Medicine, CA; Neurointerventional Surgery, California Pacific Medical Center, San Francisco (N.A.T.)
4. Neuroimaging and Neurointervention Division, Department of Radiology (M.P.M., H.M.D., R.L.D., J.J.H.)
5. Department of Neurosurgery (H.M.D., R.L.D.)
6. Department of Neurology (G.W.A., M.G.L.), Stanford School of Medicine, CA.