In vivo vocal fold cover layer replacement.

OBJECTIVES/HYPOTHESIS An animal vocal fold replacement model is needed to investigate treatments for vocal fold scarring. We developed a rabbit surgical model, hypothesizing that orthotopic vocal fold cover implants would attach and survive. We further hypothesized that superficial scarring would be limited, allowing unimpeded vibration. STUDY DESIGN Translational research: animal surgical study. METHODS Rabbit vocal fold covers were excised and immediately reimplanted. After 4 weeks, rabbits were phonated and vibration was recorded with high-speed videography. Larynges were then excised, elastic moduli measured by indentation, and covers sectioned for histology. RESULTS Five of six rabbits survived. Phonation was achieved in all, with mucosal waves evident. Elastic modulus did not differ significantly from contralateral uninjured control vocal folds. Histology demonstrated epithelial integrity, partial preservation of elastic fibers, and variable degrees of collagen deposition. CONCLUSIONS Vocal fold cover implantation in rabbits is feasible, and grafts survived. Attachment onto the thyroarytenoid muscle prevented excessive scarring, maintained tissue mechanics, and preserved mucosal vibration. LEVEL OF EVIDENCE NA.