1. Department of Otorhinolaryngology, Head and Neck Surgery; Maastricht University Medical Center; Maastricht The Netherlands
2. Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy; University of Gothenburg; Gothenburg Sweden
3. Oticon Medical AB; Askim Sweden
4. Department of Otorhinolaryngology, Head and Neck Surgery; University Medical Center Utrecht; Utrecht The Netherlands