[1] Qingdao Univ, Dept Neurosurg, Affiliated Hosp, Qingdao, Peoples R China
[2] Qingdao Univ, Affiliated Hosp, Dept Emergency Surg, Qingdao, Peoples R China
[3] Qingdao Univ, Dept Radiol, Affiliated Hosp, Qingdao, Peoples R China
[4] Qingdao Univ, Affiliated Hosp, Dept Outpatient, Qingdao, Peoples R China