title: [The related factors analysis of difficult laryngeal exposure under retaining laryngoscope].
abstract: OBJECTIVE
  To analyze the related factors of difficult laryngeal exposure under retaining laryngoscope.
  
  
  METHODS
  We did a retrospective analysis of 287 retaining laryngoscope surgery patients' clinical datas to observe the relationship between difficult glottis exposure and patients' gender, degree of mouth opening, BMI, neck circumference, head and neck flexion, TMD, HMD and SMD.
  
  
  RESULTS
  By ROC curve analysis, we determine the optimal threshold for TMD was 7.35 cm, HMD was 6.33 cm, SMD was 14.75 cm. Univariate analysis showed that gender, and glottis exposure had no significant correlation with difficult laryngeal exposure under retaining laryngoscope. Degree of mouth opening, BMI, neck circumference, head and neck flexion, TMD, HMD and SMD had correlation with difficult laryngeal exposure. Multivariate analysis showed that neck circumference, head and neck flexion, TMD, SMD were independent factors of difficult laryngeal exposure under retaining laryngoscope.
  
  
  CONCLUSIONS
  Measurement of neck circumference, head and neck flexion, TMD, SMD before the operation is important for the prediction of difficult laryngeal exposure under retaining laryngoscope.
authors.forename: Jixuan
authors.initials: J
authors.lastname: Wang
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Hu
authors.forename: Donghai
authors.initials: D
authors.lastname: Wang
authors.forename: Guofeng
authors.initials: G
authors.lastname: Zhao
authors.forename: Xiangyu
authors.initials: X
authors.lastname: Li
authors.forename: Yangyang
authors.initials: Y
authors.lastname: Li
mesh_terms: D005931:Glottis; D006257:Head; D006801:Humans; D020704:Laryngoscopes; D007828:Laryngoscopy / Q000009:adverse effects / Q000379:methods*; D007830:Larynx; D009333:Neck; D011187:Posture; D012372:ROC Curve; D012189:Retrospective Studies