1. Department of Biomedical and Clinical Sciences “Luigi Sacco”, University of Milan, Via GB Grassi 74, 20154 Milan, Italy
2. Department of Head-Neck Surgery, Otolaryngology, Head-Neck and Oral Surgery Unit, Morgagni Pierantoni Hospital, Via Carlo Forlanini 34, 47121 Forli, Italy
3. Department of ‘Organi di Senso’, University “Sapienza”, Viale dell’Università 33, 00185 Rome, Italy
4. Department of Medical and Surgical Sciences and Advanced Technologies “GF Ingrassia”, ENT Section, University of Catania, Piazza Università 2, 95100 Catania, Italy
5. Department ENT & Audiology, University of Ferrara, Via Savonarola 9, 44121 Ferrara, Italy