1. Oregon Hearing Research Center, Department of Otolaryngology, Oregon Health & Science University, 3181 Southwest Sam Jackson Park Road, Portland, OR 97239, USA.
2. Department of Otorhinolaryngology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, 173-82 Kumiro, Bundang-gu, Seongnam 463-707, Republic of Korea.
3. Department of Otology and Skull Base Surgery, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai 200031, China.