1. Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania;
2. Department of Surgery, Mayo Clinic, Rochester, Minnesota;
3. University of Pennsylvania Perelman School of Medicine and Children’s Hospital of Philadelphia, Pennsylvania;
4. The Center for Fetal Diagnosis and Treatment, Children’s Hospital of Philadelphia, Pennsylvania;
5. Department of Pediatrics, Children’s Mercy Hospital, Kansas City, Missouri; and
6. Division of Neurosurgery, Children’s Hospital of Philadelphia, Pennsylvania