Section of Neurology (EM, SR, ES, JJ, JM, RM, MS), Department of Pediatrics, University of Colorado Anschutz Medical Campus, Children's Hospital Colorado, Aurora; Section of Emergency Medicine Department of Pediatrics (RDM, JL), University of Colorado Anschutz Medical Campus, Children's Hospital Colorado, Aurora; and Division of Neurology (CAP), Department of Pediatrics, Children's Hospital of Philadelphia, PA.