1. Division of Neurosurgery, School of Child and Adolescent Health, University of Cape Town, Red Cross Children's Hospital, Cape Town, South Africa
2. Division of Neurosurgery, University of Cape Town, Red Cross Children's Hospital, Cape Town, South Africa
3. Division of Pediatric Critical Care, School of Child and Adolescent Health, University of Cape Town, Red Cross Children's Hospital, Cape Town, South Africa
4. Department of Neurosurgery, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania