[1] Hosp Univ Cent Asturias, Dept Otolaryngol, Oviedo, Spain
[2] Inst Univ Oncol Principado Asturias, Oviedo, Spain
[3] S Antonio Hosp, Div Gastroenterol, Padua, Italy
[4] Radboud Univ Nijmegen, Dept Otolaryngol Head & Neck Surg, Med Ctr, NL-6525 ED Nijmegen, Netherlands
[5] Univ Udine, ENT Clin, I-33100 Udine, Italy
[6] Montefiore Med Ctr, Dept Surg, Bronx, NY 10467 USA
[7] Montefiore Med Ctr, Dept Otolaryngol Head & Neck Surg, Bronx, NY 10467 USA
[8] Univ Liverpool, Sch Dent Sci, Liverpool L69 3BX, Merseyside, England
[9] Univ Liverpool, Dent Hosp, Liverpool L69 3BX, Merseyside, England
[10] Mayo Clin, Dept Otolaryngol Head & Neck Surg, Phoenix, AZ USA