1. Department of Ear, Nose and Throat, St George's University Hospitals NHS Foundation Trust, Tooting, London, United Kingdom
2. St. George's University Medical School, Cranmer Terrace, London, United Kingdom
3. Department of Ear, Nose and Throat, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
4. Department of Otolaryngology, Lewisham and Greenwich NHS Trust Ringgold Standard Institution, London, United Kingdom