[1] Mayo Clin, Dept Otolaryngol Head & Neck Surg, Rochester, MN USA
[2] Mayo Clin, Dept Neuroradiol, Rochester, MN USA
[3] Mayo Clin, Dept Pathol, Rochester, MN USA
[4] Mayo Clin, Dept Otolaryngol Head & Neck Surg, 200 1st St SW, Rochester, MN 55905 USA