1. Department of Neurosurgery, Keck School of Medicine, University of Southern California, Los Angeles, California
2. Department of Pathology, Childrens Hospital, Los Angeles, and Keck School of Medicine, University of Southern California, Los Angeles, California
3. Department of Radiology, Childrens Hospital, Los Angeles, and Keck School of Medicine, University of Southern California, Los Angeles, California
4. Division of Neurosurgery, Childrens Hospital, Los Angeles, and Keck School of Medicine, University of Southern California, Los Angeles, California