[1] Univ Dresden, Sch Med, Dept Otolaryngol, D-01307 Dresden, Germany
[2] Univ Bochum, St Elisabeth Hosp, Dept Otolaryngol Head & Neck Surg, Bochum, Germany
[3] Ataturk Training & Res Hosp, Clin Otolaryngol, Ankara, Turkey
[4] Int Neurosci Inst, Hannover, Germany
[5] Univ Hosp, Dept Otolaryngol Head & Neck Surg, Giessen, Germany