title: Ex vivo tracheomalacia model with 3D-printed external tracheal splint.
abstract: To design and evaluate an ex vivo model of tracheomalacia with and without a three-dimensional (3D)-printed external tracheal splint.
  
  
  
  Prospective, ex vivo animal trial.
  
  
  
  Three groups of ex vivo porcine tracheas were used: 1) control (unmanipulated trachea), 2) tracheomalacia (tracheal rings partially incised and crushed), and 3) splinted tracheomalacia (external custom tracheal splint fitted onto group 2 trachea). Each end of an ex vivo trachea was sealed with a custom-designed and 3D-printed cap; a transducer was placed through one end to measure the pressure inside the trachea. Although the negative pressure was applied to the tracheal lumen, the tracheal wall collapse was measured externally and internally using a bronchoscope. Each group had at least three recorded trials. Tracheal diameter was evaluated using ImageJ software (National Institutes of Health, Bethesda, MD) and was averaged between two raters.
  
  
  
  Average tracheal occlusion percentage was compared using Student t test. The average occlusion was 31% for group 1, 87.4% for group 2, and 20% for group 3. Significant differences were found between the control and tracheomalacia groups (P < 0.01) and the tracheomalacia and splinted tracheomalacia groups (P < 0.01). There was no significant difference between the control and splinted tracheomalacia groups (P = 0.13). Applied pressure was plotted against occlusion and regression line slope differed between the tracheomalacia (0.91) and control (0.12) or splinted tracheomalacia (0.39) groups.
  
  
  
  We demonstrate the potential for an ex vivo tracheomalacia model to reproduce airway collapse and show that this collapse can be treated successfully with a 3D-printed external splint. These results are promising and justify further studies.
  
  
  
  N/A. Laryngoscope, 127:950-955, 2017.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A.
authors.forename: Rachel
authors.initials: R
authors.lastname: Kaye
authors.affiliation: The Feinstein Institute for Medical Research, Manhasset, New York, U.S.A.|Hofstra Northwell School of Medicine, Hempstead, New York, U.S.A.
authors.forename: Todd
authors.initials: T
authors.lastname: Goldstein
authors.affiliation: Hofstra Northwell School of Medicine, Hempstead, New York, U.S.A.
authors.forename: Danielle
authors.initials: D
authors.lastname: Aronowitz
authors.affiliation: The Feinstein Institute for Medical Research, Manhasset, New York, U.S.A.|Hofstra Northwell School of Medicine, Hempstead, New York, U.S.A.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Grande
authors.affiliation: Hofstra Northwell School of Medicine, Hempstead, New York, U.S.A.|Division of Thoracic Surgery, Northwell Health, Steven and Alexandra Cohen Children's Medical Center, New Hyde Park, New York, U.S.A.
authors.forename: David
authors.initials: D
authors.lastname: Zeltsman
authors.affiliation: Hofstra Northwell School of Medicine, Hempstead, New York, U.S.A.|Division of Pediatric Otolaryngology, Steven and Alexandra Cohen Children's Medical Center, New Hyde Park, New York, U.S.A.
authors.forename: Lee P
authors.initials: LP
authors.lastname: Smith
mesh_terms: D000818:Animals; D017076:Computer-Aided Design; D004195:Disease Models, Animal; D066298:In Vitro Techniques; D066330:Printing, Three-Dimensional; D013165:Splints; D013552:Swine; D055090:Tracheomalacia / Q000628:therapy*
keywords: 3D printing; Tracheomalacia; tracheal splint; tracheal stent