1. Department of Otorhinolaryngology - Head and Neck Surgery, University of Siena, 53100 Siena, Italy.
2. Department of Otorhinolaryngology - Head and Neck Surgery, Osmangazi University, Faculty of Medicine, 26040 Eskisehir, Turkey.
3. ENT Clinic, University of Roma Tor Vergata, 00173 Rome, Italy.
4. Department of Otorhinolaryngology - Head and Neck Surgery, Kırıkkale University, Faculty of Medicine, 71450 Kırıkkale, Turkey.