Corresponding author: Armando De Virgilio, Otorhinolaryngology Unit, IRCCS Humanitas Clinical and Research Centre, via Manzoni 56, 20089 Rozzano (Mi), Italy. Tel.: +39- 02 8224 8282; Fax: +39- 02 8224 8282; E-mail: armando.devirgilio@gmail.com