title: Identification of the external branch of the superior laryngeal nerve during thyroidectomy.
abstract: OBJECTIVE
  To determine the feasibility of identification of the external branch of the superior laryngeal nerve (EBSLN) during routine thyroidectomy and to describe the EBSLN position according to the Cernea classification system.
  
  
  METHODS
  Prospective case series.
  
  
  METHODS
  Academic tertiary care center.
  
  
  METHODS
  One hundred twelve consecutive patients undergoing hemithyroidectomy or total thyroidectomy by the senior author between August 15 and December 31, 2007.
  
  
  METHODS
  None.
  
  
  METHODS
  Proportion of EBSLNs identified. Secondary outcome measures included EBSLN position according to Cernea classification and correlation with patient and gland characteristics.
  
  
  RESULTS
  Three of 178 EBSLNs (1.7%) could not be identified using the routine technique. The EBSLN was found in the highest-risk position (Cernea type 2b, crossing the superior vascular pedicle below the upper border of the gland) in 48.3% of cases, and in the lowest-risk position (Cernea type 1, crossing more than 1 cm above the upper border) in 7.3%. Specimens larger in weight and in dimension were correlated with type 2b nerves.
  
  
  CONCLUSIONS
  The EBSLN can be routinely identified during thyroidectomy. Moreover, many EBSLNs are in position to be at high risk of injury during ligation of the superior vascular pedicle.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Mount Sinai Hospital, University of Toronto, 600 University Ave, Ste 401, Toronto, ON M5G 1X5, Canada.
authors.forename: Nitin A
authors.initials: NA
authors.lastname: Pagedar
authors.forename: Jeremy L
authors.initials: JL
authors.lastname: Freeman
mesh_terms: D006801:Humans; D007823:Laryngeal Nerves / Q000033:anatomy & histology*; D009765:Obesity / Q000453:epidemiology; D009929:Organ Size; D011446:Prospective Studies; D013961:Thyroid Gland / Q000473:pathology; D013965:Thyroidectomy