1. Department of Otorhinolaryngology - Head and Neck Surgery; University Medical Center Utrecht; Utrecht The Netherlands
2. Department of Otorhinolaryngology; Jeroen Bosch Hospital; Den Bosch The Netherlands
3. Brain Center Rudolph Magnus; University Medical Center Utrecht; Utrecht the Netherlands
4. Plastic and Reconstructive Surgery Service; Memorial Sloan Kettering Cancer Center; New York NY USA
5. Department of Oral, Maxillofacial and Plastic Facial Surgery; Heinrich Braun Hospital; Zwickau Germany
6. Department of Oral, Maxillofacial and Plastic Facial Surgery; University Hospital of the Aachen University (RWTH); Aachen Germany
7. Department of Plastic and Reconstructive Surgery; Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine; Kaohsiung Taiwan
8. Department of Otolaryngology-HNS; Oregon Health and Sciences University; Portland OR USA