1. Department of Otorhinolaryngology, Head and Neck Surgery, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake-cho, Miyazaki 889-1692, Japan
2. Department of Otorhinolaryngology, Head and Neck Surgery, Kagoshima City Hospital, 37-1 Kamiaratacho, Kagoshima 890-8760, Japan