1. Division of Pediatric Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
2. Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
3. Department of Neuroradiology, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada