title: Unusual endolaryngeal extension of a large thyroglossal duct cyst.
abstract: BACKGROUND
  Thyroglossal duct cysts account for approximately 70% of congenital neck abnormalities. Hoarseness of voice and the extension of the cyst into the larynx are very uncommon.
  
  
  METHODS
  We present a patient with a long history of a large thyroglossal cyst who developed progressive hoarseness of voice. The cyst had protruded into the larynx producing the appearance of a laryngeal neoplasm. Computed tomography (CT) clearly demonstrated the nature of the cyst and its encroachment into the larynx.
  
  
  METHODS
  This was safely excised with a Sistrunk procedure and a temporary tracheostomy to maintain a secure airway, in view of the possibility of postoperative supraglottic oedema.
  
  
  CONCLUSIONS
  Endolaryngeal extension of the thyroglossal duct cyst is rare. Evaluation of unusual large midline neck masses should include a CT scan. The intralaryngeal component of the cyst can be easily dissected off from the neighbouring structures during dissection in the Sistrunk procedure. A tracheostomy may be needed.
authors.affiliation: Department of General Surgery, Singapore General Hospital, Outram Road, Singapore 169608.
authors.forename: H M
authors.initials: HM
authors.lastname: Quah
authors.forename: D T H
authors.initials: DT
authors.lastname: Lim
mesh_terms: D000328:Adult; D006685:Hoarseness / Q000209:etiology; D006801:Humans; D007830:Larynx / Q000473:pathology*; D008297:Male; D013955:Thyroglossal Cyst / Q000150:complications / Q000473:pathology* / Q000601:surgery