Affiliations

• ¹ Department of Otorhinolaryngology-Head and Neck Surgery, Helsinki University Hospital, University of Helsinki, P.O. Box 263, 00029, Helsinki, Finland. antti.makitie@helsinki.fi.
• ² Division of Ear, Nose and Throat Diseases, Department of Clinical Sciences, Intervention and Technology, Karolinska Institutet, Karolinska University Hospital, 171 76, Stockholm, Sweden. antti.makitie@helsinki.fi.
• ³ Department of Otorhinolaryngology-Head and Neck Surgery, Turku University Hospital, University of Turku, P.O. Box 52, 20521, Turku, Finland.
• ⁴ Department Otorhinolaryngology-Head and Neck Surgery, Sørlandet Hospital, 4604, Kristiansand, Norway.
• ⁵ Department of Otorhinolaryngology-Head and Neck Surgery, Landspitalinn University Hospital, Reykjavik, Iceland.
• ⁶ Sundhedshuset, 8000, Aarhus C, Denmark.
• ⁷ ENT Clinic Frohnleiten, Medical University of Graz, 8130, Graz, Austria.
• ⁸ Department of Otorhinolaryngology-Head and Neck Surgery, Skåne University Hospital, Lund University, 205 02, Malmo, Sweden.