1. Department of Otorhinolaryngology–Head and Neck SurgeryGraduate School, Kyung Hee University Seoul South Korea
2. Department of Otorhinolaryngology‐Head and Neck SurgeryMyongji Hospital, Hanyang University College of Medicine Seoul South Korea
3. Department of Otorhinolaryngology–Head and Neck SurgerySchool of Medicine, Kyung Hee University Seoul South Korea