[1] Univ Oslo, Rikshosp, Med Ctr, Dept Oto Rhino Laryngol Head & Neck Surg, N-0027 Oslo, Norway
[2] Uppsala Univ, Dept Oral & Maxillofacial Surg, S-75105 Uppsala, Sweden
[3] Uppsala Univ, Dept Oto Rhino Laryngol Head & Neck Surg, S-75105 Uppsala, Sweden
[4] Uppsala Univ, Rudbeck Lab, Dept Mol & Morpholog Pathol, Uppsala, Sweden