Comparison of thyroid, auricular, and costal cartilage donor sites for laryngotracheal reconstruction in an animal model

Objective: To evaluate and compare the use of autogenous thyroid cartilage with that of auricular and costal cartilage in laryngotracheoplasty (LTP). Design: A blinded comparison of LTP techniques using anterior thyroid, auricular, or costal cartilage as graft material in a rabbit model. Histological and anatomical analyses were performed on the laryngeal specimens 1, 4, and 6 weeks after surgery. The following factors were analyzed in each specimen: graft viability, cartilage proliferation, perichondrial viability, degree of necrosis, inflammatory response, and degree of epithelialization. Subjects: Fifty-seven New Zealand adult male rabbits, aged 6 months, were divided into 3 study groups (19 animals in each group) initially and equally into the 3 time periods. Results: No episodes of respiratory compromise occurred in any of the animals in the 3 study groups. Gross inspection of the laryngotracheal complex in the thyroid cartilage group revealed no evidence of laryngeal structural compromise. There was no statistical difference between the 3 types of cartilage used for reconstruction for the variables of graft or perichondrial viability, degree of necrosis, or inflammatory response at 1, 4, or 6 weeks. Cartilage proliferation in the thyroid cartilage group was decreased compared with that in the other 2 groups at 1 week. The amount of proliferation increased in this group and was equal to the amount present in the other 2 groups 4 and 6 weeks after surgery. Complete epithelialization of the graft material was present in all 3 groups at 4 and 6 weeks after reconstruction. Conclusions: The use of autogenous thyroid cartilage for LTP compares favorably with that of other methods of reconstruction that use either auricular or costal cartilage in the rabbit model. This technique is a viable alternative for single-stage LTP and has the added advantage of using a single incision.