1. Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
2. Department of Neurology, The Royal Children’s Hospital, Melbourne, Australia
3. Division of Histopathology, The Hospital for Sick Children, Toronto, Ontario, Canada
4. Department of Neuroradiology, The Hospital for Sick Children, Toronto, Ontario, Canada
5. Departments of Neurology and Pediatrics, University of California San Francisco, San Francisco, California