1 Aichi Children's Health and Medical Center, Aichi, Japan; Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
2 Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, Nagoya, Japan. Electronic address: tadaoy@med.nagoya-u.ac.jp.
3 Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
4 Aichi Children's Health and Medical Center, Aichi, Japan.