[1] Chris O Brien Lifehouse, Dept Head & Neck Surg, 119-143 Missenden Rd, Camperdown, NSW 2050, Australia
[2] Univ Sydney, Fac Med & Hlth, Sydney Med Sch, Anderson Stuart Bldg, Camperdown, NSW 2006, Australia
[3] Royal Prince Alfred Inst Acad Surg, Sydney Local Hlth Dist, 145 Missenden Rd, Camperdown, NSW 2050, Australia
[4] Macquarie Univ, Fac Med & Hlth Sci, Dept Otolaryngol Head & Neck Surg, Sydney, Australia