1. Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, 2300 RC Leiden, Netherlands
2. Percuros B.V., 7522 NB Enschede, Netherlands
3. Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, 3508 GA Utrecht, Netherlands
4. Brain Center Rudolf Magnus, University Medical Center Utrecht, 3508 GA Utrecht, Netherlands
5. Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, 2300 RC Leiden, Netherlands