1. Department of Otorhinolaryngology, Seoul National University College of Medicine, Seoul, Korea.
2. Department of Otolaryngology, Gyeongsang National University College of Medicine, Jinju, Korea.
3. Department of Otolaryngology, Hallym University College of Medicine, Anyang, Korea.
4. Research Center for Sensory Organs, Medical Research Center, Seoul National University, Seoul, Korea.