title: Anatomical location of the vocal cords in relation to cervical vertebrae: A new predictor of difficult laryngoscopy?
abstract: BACKGROUND
  Several anatomical factors, such as prognathism, sex, short thyromental distance and others are known to make direct laryngoscopy difficult.
  
  
  OBJECTIVE
  We investigated the hypothesis that the anatomical position of the vocal cords in relation to the cervical vertebrae correlates with difficult laryngoscopy. Existing MRI was used to identify the position of the vocal cords relative to the cervical spine in patients with and without difficult laryngoscopy.
  
  
  METHODS
  Observational study with adaptive enrichment.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  A total of 142 adult patients, 91 with easy (Cormack-Lehane class 1 or 2) and 51 with difficult (Cormack-Lehane class 3 or 4) laryngoscopy.
  
  
  METHODS
  Position of the vocal cords relative to cervical vertebrae in patients with easy vs. difficult laryngoscopy.
  
  
  RESULTS
  In patients with difficult laryngoscopy, we found a higher incidence of cranial position of the vocal cords in relation to the cervical spine compared with patients with easy laryngoscopy (P < 0.001).
  
  
  CONCLUSIONS
  Anaesthesiologists should take advantage of existing imaging of the cervical spine when assessing the patient's airway.
authors: From the Department of Anaesthesiology (TM, HS, MH, HI); Department of Neurosurgery, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany (SS); and Department of Anaesthesiology, Perioperative and Pain Medicine, School of Medicine, Stanford University, Stanford, California, USA (AT).
authors: Tino
authors: T
authors: Münster
authors: Melanie
authors: M
authors: Hoffmann
authors: Sven
authors: S
authors: Schlaffer
authors: Harald
authors: H
authors: Ihmsen
authors: Hubert
authors: H
authors: Schmitt
authors: Alexander
authors: A
authors: Tzabazis
mesh_terms: D059925:Anatomic Landmarks; D002574:Cervical Vertebrae / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D006785:Hospitals, University; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects / Q000295:instrumentation; D007828:Laryngoscopy / Q000009:adverse effects / Q000295:instrumentation; D008279:Magnetic Resonance Imaging; D011237:Predictive Value of Tests; D012307:Risk Factors; D014827:Vocal Cords / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*