1 Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, Tygerberg Hospital, Stellenbosch University, Cape Town, South Africa.
2 Department of Pediatric Radiology, The Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, Pennsylvania.
3 Department Otorhinolaryngology, Faculty of Medicine and Health Sciences, Tygerberg Hospital, Stellenbosch University, Cape Town, South Africa.