The effects of mitomycin-C and stenting on airway wound healing after laryngotracheal reconstruction in a pig model

Citation
G. Coppit et al., The effects of mitomycin-C and stenting on airway wound healing after laryngotracheal reconstruction in a pig model, INT J PED O, 53(2), 2000, pp. 125-135
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Otolaryngology
Journal title
INTERNATIONAL JOURNAL OF PEDIATRIC OTORHINOLARYNGOLOGY
ISSN journal
0165-5876 → ACNP
Volume
53
Issue
2
Year of publication
2000
Pages
125 - 135
Database
ISI
SICI code
0165-5876(20000630)53:2<125:TEOMAS>2.0.ZU;2-E
Abstract
Objective: To assess the effects of mitomycin-C (MTC) acid endoscopic stent ing on airway wound healing after laryngotracheal reconstruction. Design:A prospective, blinded, randomized controlled animal study. Subjects: Twenty- six domestic pigs (Sus scrofula) divided into four groups. Interventions: E ach animal underwent single-stage laryngotracheal reconstruction (SSLTR) wi th auricular cartilage grafts and stenting. Group 1 animals were sacrificed on postoperative day 3, and group 2 animals on postoperative day 7. On pos toperative day 7, groups 3 and 4 underwent endoscopy, stent removal, and ap plication of MTC (0.5 mg/ml) or placebo (normal saline). Group 3 animals we re sacrificed on postoperative day 14, group 4 animals on day 21. Two addit ional animals from each experimental group were prepared for election micro scopy studies. Segments of reconstructed airway were evaluated grossly and histologically for all animals. Additional tonometric evaluation was perfor med on two stents to determine their compressive strength. Main outcome mea sures: Healing, reepithelization, graft incorporation, and airway diameter. Results: Two-thirds of the animals demonstrated some degree of stent colla pse on endoscopy. Granulation tissue formation was seen in all animals, and resolved with stent removal. No animal experienced airway compromise due t o granulation tissue formation. Stenting was seen to induce a submucosal fi broproliferative response and scarring, with loss of normal glandular archi tecture, in all animals. MTC did not affect the acute inflammatory response , reepithelization of the graft site, or formation of the subepithelial fib roproliferative response. MTC treated animals, however, demonstrated better graft incorporation with fibrocartilage proliferation of the graft. Untrea ted animals demonstrated liquefactive necrosis of the graft, without eviden ce of neochondrification of the graft. Conclusions: The pig airway is an ad equate model of wound healing following SSLTR and stenting. Metallic ballon expandable stents can be successfully used following SSLTR, allowing for i mmediate postoperative extubation. However, the formation of a submucosal f ibroproliferative response and mucosal scarring seen in our study raises so me concerns with the current stent design. Before stenting is widely clinic ally applied, the optimum stent design needs to be developed. Finally, MTC seems to prevent the liquefactive necrosis of SSLTR grafts and promote neoc hondrification, allowing improved graft incorporation. Further studies are needed to asses the long-term effects of MTC on healing and restenosis, and its effects on cartilage growth and formation, following SSLTR. (C) 2000 E lsevier Science Ireland Ltd. All rights reserved.