1. Faculty of Medicine and Surgery, University of Enna “Kore”, 94100 Enna, Italy
2. Department of Medical and Surgical Sciences and Advanced Technologies “GF Ingrassia”, ENT Section, University of Catania, Via S. Sofia, 78, 95125 Catania, Italy
3. Division of Rheumatology, A.O.U. “Policlinico-San Marco”, 95123 Catania, Italy
4. Ophthalmology Clinic, San Marco Hospital, University of Catania, 95123 Catania, Italy
5. Department of Anaesthesia and Intensive Care, University Hospital Policlinico-San Marco, 24046 Catania, Italy
6. Service of Otolaryngology, Hospital Complex of Santiago de Compostela, 15701 Santiago de Compostela, Spain