title: Comparison of swallowing outcomes of laryngotracheal separation versus total laryngectomy in a validated ovine model of profound oropharyngeal dysphagia.
abstract: OBJECTIVE
  To validate the ovine model of profound oropharyngeal dysphagia and compare swallowing outcomes of laryngotracheal separation with those of total laryngectomy.
  
  
  METHODS
  Under real-time fluoroscopy, swallowing trials were conducted using the head and neck of two Dorper cross ewes and one human cadaver, secured in lateral fluoroscopic orientation. Barium trials were administered at baseline, pre- and post-laryngohyoid suspension, following laryngotracheal separation, and following laryngectomy in the ovine model.
  
  
  RESULTS
  Mean pre-intervention Penetration Aspiration Scale and National Institutes of Health Swallow Safety Scale scores were 8 ± 0 and 6 ± 0 respectively in sheep and human cadavers, with 100 per cent intra- and inter-species reproducibility. These scores improved to 1 ± 0 and 2 ± 0 post-laryngohyoid suspension (p < 0.01). Aerodigestive tract residue was 18.6 ± 2.4 ml at baseline, 15.4 ± 3.8 ml after laryngotracheal separation and 3.0 ± 0.7 ml after total laryngectomy (p < 0.001).
  
  
  CONCLUSIONS
  The ovine model displayed perfect intra- and inter- species reliability for the Penetration Aspiration Scale and Swallow Safety Scale. Less aerodigestive tract residue after narrow-field laryngectomy suggests that swallowing outcomes after total laryngectomy are superior to those after laryngotracheal separation.
authors.affiliation: Center for Voice and Swallowing,Department of Otolaryngology - Head and Neck Surgery,University of California,Davis,USA.
authors.forename: N N
authors.initials: NN
authors.lastname: Venkatesan
authors.affiliation: Department of Otolaryngology - Head and Neck Surgery,Medical College of Georgia,Augusta University,USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Johnson
authors.affiliation: Center for Voice and Swallowing,Department of Otolaryngology - Head and Neck Surgery,University of California,Davis,USA.
authors.forename: M T
authors.initials: MT
authors.lastname: Siddiqui
authors.affiliation: Center for Voice and Swallowing,Department of Otolaryngology - Head and Neck Surgery,University of California,Davis,USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Cates
authors.affiliation: Center for Voice and Swallowing,Department of Otolaryngology - Head and Neck Surgery,University of California,Davis,USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Kuhn
authors.affiliation: Department of Otolaryngology - Head and Neck Surgery,Medical College of Georgia,Augusta University,USA.
authors.forename: G N
authors.initials: GN
authors.lastname: Postma
authors.affiliation: Center for Voice and Swallowing,Department of Otolaryngology - Head and Neck Surgery,University of California,Davis,USA.
authors.forename: P C
authors.initials: PC
authors.lastname: Belafsky
mesh_terms: D000818:Animals; D002102:Cadaver; D003679:Deglutition / Q000502:physiology*; D003680:Deglutition Disorders / Q000503:physiopathology / Q000601:surgery*; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D007825:Laryngectomy / Q000379:methods*; D007828:Laryngoscopy / Q000379:methods*; D007830:Larynx / Q000601:surgery; D011184:Postoperative Period; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D012756:Sheep; D014132:Trachea / Q000601:surgery; D016896:Treatment Outcome
keywords: Deglutition Disorders; Experimental Animal Model; Laryngectomy; Respiratory Aspiration; Surgical Models