1 Department of Otorhinolaryngology-Head and Neck Surgery (Kuo, Wang), Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan; Graduate Institute of Medical Sciences (Wang), National Defense Medical Center, Taipei, Taiwan.
2 Department of Otorhinolaryngology-Head and Neck Surgery (Kuo, Wang), Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan; Graduate Institute of Medical Sciences (Wang), National Defense Medical Center, Taipei, Taiwan chw@ms3.hinet.net.