1 Department of Otorhinolaryngology, Head Neck Surgery, Medical University of Vienna, Vienna, Austria.
2 Institute of Head and Neck Diseases, Evangelical Hospital, Vienna, Austria.
3 Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan.
4 Center of Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria.
5 Department of Surgery-Otorhinolaryngology, Head and Neck Surgery, The Queen Elizabeth Hospital, Australia and University of Adelaide, Adelaide, Australia.
6 Otolaryngology Department, Pontificia Universidad Católica de Chile, Santiago, Chile.