1 Department of Otolaryngology, Royal Aberdeen Children's Hospital, Aberdeen, Scotland, United Kingdom. Electronic address: panagiotis.asimakopoulos@nhs.net.
2 Department of Otolaryngology, Royal Aberdeen Children's Hospital, Aberdeen, Scotland, United Kingdom.
3 Department of Radiology, Sidra Medical and Research Center, Doha, Qatar.
4 Department of Anaesthetics, Royal Aberdeen Children's Hospital, Aberdeen, Scotland, United Kingdom.