[1] Johns Hopkins Univ, Sch Med, Dept Otolaryngol Head & Neck Surg, Baltimore, MD 21205 USA
[2] Univ Calif Davis, Med Ctr, Dept Radiol, Sacramento, CA 95817 USA
[3] UC Davis Childrens Hosp, Sacramento, CA USA
[4] Univ Kansas, Sch Med, Dept Otolaryngol Head & Neck Surg, Kansas City, KS USA