Effect of harvesting autogenous laryngeal cartilage for laryngotracheal reconstruction on laryngeal growth and support.

OBJECTIVE: Determine the effect of harvesting autogenous thyroid cartilage on subsequent laryngeal growth and stability in a kitten model.

STUDY DESIGN: Prospective controlled trial in animals.

METHODS: Seventeen kittens were divided into three groups. Group one (n = 5) included kittens that underwent a unilateral thyroid cartilage resection. Group two (n = 5) included kittens that underwent a bilateral cartilage resection. Group three (n = 7) comprised kittens that did not undergo any surgical procedure (controls). All animals underwent endoscopic examination followed by the surgical procedure designated for that group. Kittens were then assessed daily for 2.5 months. At the end of that period the now "adolescent" cats were examined endoscopically then euthanized. The larynx was removed for gross and histopathologic analysis.

RESULTS: All kittens tolerated the surgical procedure without airway compromise. Subsequent endoscopic examination 2.5 months after surgery revealed normal vocal cord function. Measurements of the true vocal cord and aryepiglottic and subglottic diameter did not differ significantly (one-way analysis of variance, P = .05) with respect to the side or the group. Histopathologic evaluation of the laryngeal sections indicated a patent airway, stable and viable thyroid cartilage, and no evidence of cartilaginous regrowth.

CONCLUSIONS: The removal of unilateral and bilateral superior thyroid alar cartilage can be performed in kittens without postoperative respiratory or wound problems. The harvesting of autogenous thyroid cartilage has no apparent effect on subsequent laryngeal growth and stability in a kitten model.