1. Division of Otolaryngology, Azienda Ospedaliero Universitaria, 07100 Sassari, Italy
2. U.O.C. Otorinolaringoiatria, Università degli Studi di Cagliari, Policlinico Universitario Duilio Casula, 09042 Monserrato, Italy
3. Institute of Pathology, Azienda Ospedaliero Universitaria, 07100 Sassari, Italy
4. Department of Medicine, Surgery and Pharmacology, University of Sassari, 07100 Sassari, Italy
5. Otolaryngology, Mater Olbia Hospital, 07026 Olbia, Italy