1. Department of Otorhinolaryngology, Head & Neck Surgery, University Clinic St. Poelten, Dunant-Platz 1, 3100 St. Pölten, Austria
2. Karl Landsteiner Institute of Implantable Hearing Devices, 3100 St. Pölten, Austria
3. Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Comprehensive Hearing Center, University of Wuerzburg, Josef-Schneider-Str. 11, 97080 Würzburg, Germany
4. ENT Department, Antwerp University Hospital, Wilrijkstraat 10, 2650 Antwerp, Belgium
5. Department of Otolaryngology, La Paz University Hospital, 28046 Madrid, Spain