[1] Catholic Univ Korea, Seoul St Marys Hosp, Coll Med, Dept Otorhinolaryngol Head & Neck Surg, Seoul, South Korea
[2] Cincinnati Childrens Hosp, Dept Pediat Otolaryngol, Cincinnati, OH USA
[3] Nara Informat Co Ltd, Seoul, South Korea
[4] Catholic Univ Korea, Seoul St Marys Hosp, Coll Med, Dept Otorhinolaryngol Head & Neck Surg, 222 Banpo Daero, Seoul 06591, South Korea