1. Department of Otolaryngology, County General and Veterans Hospital Vukovar, Zupanijska, Vukovar, Croatia
2. Department of Ophthalmology, Optometry and Otorhinolaryngology, Faculty of Dental Medicine and Health, Crkvena, Osijek, Croatia
3. Department of Otorhinolaryngology and Maxillofacial Surgery, Medical Faculty, University of Osijek, J. Huttlera, Osijek, Croatia
4. Department of Otorhinolaryngology and Head and Neck Surgery, Clinical Hospital Centre Osijek, J. Huttlera, Osijek, Croatia