Novel Extraluminal silicone tracheal stent: Development and evaluation in a rabbit model of tracheomalacia

Abstract

Tracheal collapse (TC), defined by excessive tracheal collapsibility, often results in severe respiratory distress in small-breed dogs. Surgical intervention, including the placement of extraluminal stents, has been employed as a treatment option. Owing to the anatomical and physiological similarities between rabbit and canine tracheas, a rabbit model was utilized to develop a novel extraluminal silicone tracheal stent and evaluate its feasibility in treating tracheomalacia. The stent was surgically implanted in eight New Zealand White rabbits after the induction of tracheomalacia. Postoperative evaluations, including clinical assessment, radiography, computed tomography (CT), and histological analysis, were performed at 1, 2, and 6 months post-implantation. All rabbits in the stent group survived without exhibiting signs of respiratory distress, whereas all rabbits in the tracheomalacia group experienced respiratory distress, with one succumbing to respiratory failure. Radiographic and CT evaluations confirmed that the stent effectively maintained airway patency, with tracheal measurements not significantly different from the preoperative values, indicating successful restoration of tracheal diameter. Histological analysis demonstrated minimal inflammatory response, the absence of fibrosis, and preserved structural integrity of the tracheal cartilage. Therefore, the novel extraluminal silicone tracheal stent provides effective airway support while minimizing adverse tissue reactions. Further studies, including the use of this stent in a canine TC model and assessment of its long-term outcomes, are warranted to explore its potential clinical applications in veterinary medicine.

Keywords

extraluminal tracheal stent / rabbit model / silicone / tracheal collapse / tracheomalacia

References

[1] Tangner C, Hobson HP. A retrospective study of 20 surgically managed cases of collapsed trachea. Vet Surg. 1982; 11(4): 146-149.

[2] Buback JL, Boothe HW, Hobson HP. Surgical treatment of tracheal collapse in dogs: 90 cases (1983-1993). J Am Vet Med Assoc. 1996; 208(3): 380-384.

[3] Johnson L. Tracheal collapse: diagnosis and medical and surgical treatment. Vet Clin North Am Small Anim Pract. 2000; 30(6): 1253-1266.

[4] Durant AM, Sura P, Rohrbach B, Bohling MW. Use of nitinol stents for end-stage tracheal collapse in dogs. Vet Surg. 2012; 41(7): 807-817.

[5] Johnson L, Pollard R. Tracheal collapse and bronchomalacia in dogs: 58 cases (7/2001-1/2008). J Vet Intern Med. 2010; 24(2): 298-305.

[6] Hall E, Baines E, Baines S. Atypical lateral tracheal collapse in a Yorkshire terrier. J Small Anim Pract. 2020; 61(10): 644-647.

[7] Chisnell HK, Pardo AD. Long-term outcome, complications and disease progression in 23 dogs after placement of tracheal ring prostheses for treatment of extrathoracic tracheal collapse. Vet Surg. 2015; 44(1): 103-113.

[8] Tappin SW. Canine tracheal collapse. J Small Anim Pract. 2016; 57(1): 9-17.

[9] Payne JD, Mehler SJ, Weisse C. Tracheal collapse. Compend Contin Educ Vet. 2006; 28(5): 373-383.

[10] Beranek J, Jaresova H, Rytz U. Use of nitinol self-expandable stents in 26 dogs with tracheal collapse. Schweiz Arch Tierheilkd. 2014; 156(2): 91-98.

[11] Sun F, Usón J, Ezquerra J, Crisóstomo V, Luis L, Maynar M. Endotracheal stenting therapy in dogs with tracheal collapse. Vet J. 2008; 175(2): 186-193.

[12] Weisse C, Berent A, Violette N, McDougall R, Lamb K. Short-, intermediate-, and long-term results for endoluminal stent placement in dogs with tracheal collapse. J Am Vet Med Assoc. 2019; 254(3): 380-392.

[13] Woo H-M, Kim M-J, Lee S-G, et al. Intraluminal tracheal stent fracture in a Yorkshire terrier. Can Vet J. 2007; 48(10): 1063-1066.

[14] Moser JE, Geels JJ. Migration of extraluminal tracheal ring prostheses after tracheoplasty for treatment of tracheal collapse in a dog. J Am Vet Med Assoc. 2013; 243(1): 102-104.

[15] Ayres SA, Holmberg DL. Surgical treatment of tracheal collapse using pliable total ring prostheses: results in one experimental and 4 clinical cases. Can Vet J. 1999; 40(11): 787-791.

[16] Kaye R, Goldstein T, Aronowitz D, Grande DA, Zeltsman D, Smith LP. Ex vivo tracheomalacia model with 3D-printed external tracheal splint. Laryngoscope. 2017; 127(4): 950-955.

[17] Mondal A, Visner GA, Kaza AK, Dupont PE. A novel ex vivo tracheobronchomalacia model for airway stent testing and in vivo model refinement. J Thorac Cardiovasc Surg. 2023; 166(3): 679-687.e1.

[18] Tsukada H, O'Donnell CR, Garland R, Herth F, DeCamp M, Ernst A. A novel animal model for hyperdynamic airway collapse. Chest. 2010; 138(6): 1322-1326.

[19] Morrison RJ, Hollister SJ, Niedner MF, et al. Mitigation of tracheobronchomalacia with 3D-printed personalized medical devices in pediatric patients. Sci Transl Med. 2015; 7(285): 285ra64-285ra64.

[20] Gorostidi F, Courbon C, Burki M, Reinhard A, Sandu K. Extraluminal biodegradable splint to treat upper airway anterior malacia: a preclinical proof of principle. Laryngoscope. 2018; 128(2): E53-E58.

[21] Kim JH, Choi JY, Yoon HY. A rabbit model of tracheal collapse for optimal self-expanding metal stents. J Vet Med Sci. 2023; 85(3): 386-392.

[22] Novotny L, Crha M, Rauser P, et al. Novel biodegradable polydioxanone stents in a rabbit airway model. J Thorac Cardiovasc Surg. 2012; 143(2): 437-444.

[23] Macready DM, Johnson LR, Pollard RE. Fluoroscopic and radiographic evaluation of tracheal collapse in dogs: 62 cases (2001-2006). J Am Vet Med Assoc. 2007; 230(12): 1870-1876.

[24] Mostafa AA, Berry CR. Radiographic vertical tracheal diameter assessment at different levels along the trachea as an alternative method for the evaluation of the tracheal diameter in non-brachycephalic small breed dogs. BMC Vet Res. 2022; 18(1): 61.

[25] Gallet P, Phulpin B, Merlin J-L, et al. Long-term alterations of cytokines and growth factors expression in irradiated tissues and relation with histological severity scoring. PLoS One. 2011; 6(12): e29399.

[26] Suematsu M, Suematsu H, Minamoto T, Machida N, Hirao D, Fujiki M. Long-term outcomes of 54 dogs with tracheal collapse treated with a continuous extraluminal tracheal prosthesis. Vet Surg. 2019; 48(5): 825-834.

[27] Sura PA, Krahwinkel DJ. Self-expanding nitinol stents for the treatment of tracheal collapse in dogs: 12 cases (2001-2004). J Am Vet Med Assoc. 2008; 232(2): 228-236.

[28] Den Hondt M, Vanaudenaerde BM, Delaere P, Vranckx JJ. Twenty years of experience with the rabbit model, a versatile model for tracheal transplantation research. Plast Aesthet Res. 2016; 3(7): 223.

[29] Habal MB. The biologic basis for the clinical application of the silicones: a correlate to their biocompatibility. Arch Surg. 1984; 119(7): 843-848.

[30] Théron M-L, Lahuerta-Smith T. Laryngeal silicone stent as a treatment option for laryngeal paralysis in dogs: a preliminary study of 6 cases. J Vet Sci. 2022; 23(4): e58.

[31] Kim D-H, Choi C-B, Chung W-H, et al. Preliminary study for a newly designed silicone stent and delivery system for canine obstructive tracheal disease. J Vet Med Sci. 2012; 74(10): 1323-1326.

[32] De Lorenzi D, Maggi G, Bertoncello D, Porciello F, Marchesi MC. Dumon silicone stents can improve respiratory function in dogs with grade IV tracheal collapse: 12 cases (2019-2023). J Am Vet Med Assoc. 2024; 1(aop): 1-7.

[33] Gildea TR, Young BP, Machuzak MS. Application of 3D printing for patient-specific silicone stents: 1-year follow-up on 2 patients. Respiration. 2018; 96(5): 488-494.

[34] Abbas H, Nasim F. Advances in airway stenting. Curr Pulmonol Rep. 2024; 13(1): 87-94.

RIGHTS & PERMISSIONS

2025 The Author(s). Animal Models and Experimental Medicine published by John Wiley & Sons Australia, Ltd on behalf of The Chinese Association for Laboratory Animal Sciences.