[1] Univ Wisconsin, Ctr Clin Sci H4310, Sch Med, Div Otolaryngol Head & Neck Surg, Madison, WI 53792 USA
[2] Univ Wisconsin, Dept Surg, Sch Med, Madison, WI 53792 USA
[3] Univ Wisconsin, Dept Rehabil Med & Neurol, Sch Med, Madison, WI 53792 USA
[4] Univ Wisconsin, Dept Anat, Sch Med, Madison, WI 53792 USA