1. Department of Otolaryngology—Head and Neck Surgery, Chang Gung Memorial Hospital, Chiayi 613, Taiwan
2. Faculty of Medicine, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
3. Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
4. Head and Neck Infection Treatment Center, Chang Gung Memorial Hospital, Chiayi 613, Taiwan