1. Department of Otorhinolaryngology, Head and Neck Surgery, “Otto Koerner” Rostock University Medical Center Rostock Germany
2. Institute of Diagnostic and Interventional Radiology, Pediatric and Neuroradiology Rostock University Medical Center Rostock Germany
3. Department of Otolaryngology‐Head and Neck Surgery and Neurological Surgery University of Texas; Southwestern Medical Center in Dallas Dallas Texas U.S.A.
4. MED‐EL Innsbruck Austria