Autologous fat injection for vocal fold paralysis: long-term histologic evaluation

Many techniques have been developed for medialization of the paralyzed vocal fold. The purpose of this study is to evaluate autologous fat as an alternative to alloplastic substances for use in vocal fold medialization. Eight dogs underwent left recurrent laryngeal nerve sectioning. Autologous fat was harvested, and the paralyzed vocal fold was medialized by injecting the fat into the thyroarytenoid muscle. The animals were divided into three groups for evaluation at 1, 3, and 6 months. Videolaryngoscopy was performed prior to sacrificing the animals. The larynges were sectioned coronally, and histologic studies were performed. The studies confirmed the preservation of viable fat at the injected site in all animals. Only a minimal inflammatory response was observed in the 1-month group. It would appear that fat injection is a viable alternative to Teflon injection and thyroplasty; it eliminates the need for alloplastic materials, does not appear to migrate, and does not require an open procedure.