1. Department of Otorhinolaryngology, Saiseikai Gose Hospital, 20 Mimuro, Gose, Nara 639–2306, Japan
2. Department of Otorhinolaryngology, Kinki University Nara Hospital, Ikoma, Nara, Japan
3. Department of Otorhinolaryngology and Head & Neck Surgery, Nara Medical University, Kashihara, Nara, Japan