1. 1 University Clinic of Ear, Nose and Throat – Faculty of Medicine, Ss. Cyril and Methodius University in Skopje , RN Macedonia
2. 2 Institute of Radiology, Faculty of Medicine , Ss. Cyril and Methodius University in Skopje , RN Macedonia
3. 3 University Clinic of Neurology, Faculty of Medicine, Ss. Cyril and Methodius University in Skopje , RN Macedonia
4. 4 Department of ENT Medicine, Head and Neck Surgery , Hansa Private Hospital , Graz , Austria