1 Ningxia Medical University, Ningxia, China; Department of Otolaryngology Head and Neck Surgery, Gansu Maternal and child Health Care Hospital, Gansu, China.
2 Department of Otolaryngology Head and Neck Surgery, Second Affiliated Hospital of Ningxia Medical University Yinchuan First People's Hospital, Ningxia, China.
3 Ningxia Medical University, Ningxia, China.
4 Department of Otolaryngology Head and Neck Surgery, Second Affiliated Hospital of Ningxia Medical University Yinchuan First People's Hospital, Ningxia, China. Electronic address: maruixia4368@sina.com.