1 Departments of Neurology, Pediatrics, and Radiology, Washington University School of Medicine, 660 S. Euclid Ave MSC 8111-43-1260, St. Louis, MO, 63110, USA. kristinguilliams@wustl.edu.
2 Division of Child Neurology, Children's National Hospital, 111 Michigan Ave, NW, Washington, District of Columbia, 20010, USA.