1. From the Departments of Neurology and Neurological Surgery (A.R.Z., M.N.D., W.J.P.), Anesthesia (M.N.D.), and Radiology (C.P.D., W.J.P.), Lillian Strauss Institute for Neuroscience of the Jewish Hospital of St Louis, and the Neurology/Neurosurgery Intensive Care Unit, Washington University, St Louis, Mo.