1. Department of Otolaryngology, Hospital of the Sick (Ospedale Degli Infermi), Biella, Italy
2. Department of Otolaryngology (Ear, Nose and Throat), University of Pavia, Pavia, Italy
3. Department of Otolaryngology (Ear, Nose and Throat), Hospital of the Sick (Ospedale Degli Infermi), Biella, Italy