[1] Hosp Nostra Senyora de Meritxell, Dept Otorhinolaryngol, Andorra La Vella, Andorra
[2] Univ Autonoma Barcelona, Hosp Santa Creu & St Pau, Dept Otorhinolaryngol, C Mas Casanovas 90, Barcelona 08041, Spain
[3] Univ Int Catalunya, Hosp Gen Catalunya, Dept Otorhinolaryngol, Barcelona, Spain
[4] Ctr Invest Biomed Red Bioingn Biomat & Nanomed CI, Madrid, Spain