1. Department of Otolaryngology, University of Turin, “San Luigi Gonzaga” Hospital, Regione Gonzole 10, Orbassano, 10043 Turin, Italy
2. Otolaryngology Unit, Santi Paolo e Carlo Hospital, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy
3. Otolaryngology Unit, ASST Santi Paolo e Carlo, Università degli Studi di Milano, 20142 Milan, Italy
4. ASP Ragusa-Hospital Giovanni Paolo II, 97100 Ragusa, Italy
5. Department of Medical and Surgical Sciences and Advanced Technologies “GF Ingrassia”, ENT Section, University of Catania, Via S. Sofia, 78, 95125 Catania, Italy
6. Otorhinolaryngology, “A. Gemelli” Unversitary Hospital IRCCS, 00168 Rome, Italy
7. Department of Medicine and Surgery, School of Medicine, University of Enna “Kore”, 94100 Enna, Italy