[1] Evangel Hosp, Inst Head & Neck Dis, A-1180 Vienna, Austria
[2] Clin Hosp Ctr Rijeka, Dept Otorhinolaryngol Head & Neck Surg, Rijeka 51000, Croatia
[3] Univ Rijeka, Fac Med, Rijeka 51000, Croatia
[4] Med Univ Vienna, Dept Otorhinolaryngol Head & Neck Surg, A-1090 Vienna, Austria
[5] Med Univ Vienna, Ctr Med Stat Informat & Intelligent Syst, Sect Med Stat, A-1090 Vienna, Austria
[6] Clin Hosp Ctr Rijeka, Dept Audiol & Phoniatr, Rijeka 51000, Croatia
[7] Clin Hosp Ctr Rijeka, Clin Dept Pathol & Cytol, Rijeka 51000, Croatia