title: Angiogenesis in costal cartilage graft laryngotracheoplasty: a corrosion casting study in piglets.
abstract: OBJECTIVE
  To investigate the timing and degree of angiogenesis following anterior costal cartilage graft laryngotracheoplasty in an animal model.
  
  
  METHODS
  Randomized controlled animal model.
  
  
  METHODS
  Twelve pigs were included in this study. Three control pigs were perfused with intravascular methyl methacrylate, and overlying tissue was corroded with potassium hydroxide and hydrochloric acid, leaving only a cast of vessels. Nine pigs underwent anterior costal cartilage graft laryngotracheoplasty and were survived for various lengths of time (3 for 48 hours, 3 for 10 days, 3 for 3 weeks) prior to corrosion casting. Transition zones between trachea and cartilage graft as well as the graft itself were analyzed for signs of angiogenesis (budding, sprouting, intussusception) and hypoxic or degenerative vessel features (extravasation, corrugation, circular constriction) using scanning electron microscopy.
  
  
  RESULTS
  Angiogenesis peaked above control levels 48 hours after laryngotracheoplasty (P < .0001) and decreased 10 days and 3 weeks following surgery (P < .001, P < .0001, respectively) while remaining elevated above control levels (P < .0001, P < .005, respectively). There was no difference in hypoxic or degenerative features across surgical and control groups. Sprouting angiogenesis dominated over intussusception preoperatively (P < .0001) and 3 weeks following surgery (P < .05). However, there was no difference in type of angiogenesis 48 hours and 10 days following surgery.
  
  
  CONCLUSIONS
  Angiogenesis peaked by 48 hours following costal cartilage graft laryngotracheoplasty and persisted for at least 3 weeks (although decreased) after surgery in this animal model. Hypoxic or degenerative processes did not appear to play a role in tracheal revascularization during the first 3 postoperative weeks.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, The Hospital for Sick Children, University of Toronto, Toronto, Canada.
authors.forename: Lukas H
authors.initials: LH
authors.lastname: Kus
authors.forename: Jaina
authors.initials: J
authors.lastname: Negandhi
authors.forename: Michael C
authors.initials: MC
authors.lastname: Sklar
authors.forename: Antoine
authors.initials: A
authors.lastname: Eskander
authors.forename: Marvin
authors.initials: M
authors.lastname: Estrada
authors.forename: Robert V
authors.initials: RV
authors.lastname: Harrison
authors.forename: Paolo
authors.initials: P
authors.lastname: Campisi
authors.forename: Vito
authors.initials: V
authors.lastname: Forte
authors.forename: Evan J
authors.initials: EJ
authors.lastname: Propst
mesh_terms: D000818:Animals; D016319:Corrosion Casting; D066186:Costal Cartilage / Q000637:transplantation*; D004195:Disease Models, Animal; D005500:Follow-Up Studies; D058753:Laryngoplasty / Q000379:methods*; D007829:Laryngostenosis / Q000601:surgery*; D007830:Larynx / Q000098:blood supply* / Q000601:surgery; D018919:Neovascularization, Physiologic; D013552:Swine; D014132:Trachea / Q000098:blood supply / Q000601:surgery*
keywords: Angiogenesis; animal model; corrosion casting; costal cartilage graft; laryngotracheoplasty