EELCO F. M. WIJDICKS, M.D., Ph.D., F.A.C.P., Professor of Neurology, College of Medicine, Chair, Division of Critical Care Neurology, Consultant, Neurosciences Intensive Care Unit, Saint Marys Hospital, Mayo Clinic, Rochester, Minnesota ALEJANDRO A. RABINSTEIN, M.D., Professor of Neurology, College of Medicine, Division of Critical Care Neurology, Medical Director and Consultant, Neurosciences Intensive Care Unit, Saint Marys Hospital, Mayo Clinic, Rochester, Minnesota