Lipoinjection in the paralyzed feline vocal fold: study of graft survival

Six adult domestic strain cats were used to study the long-term histologic outcome of injected autologous fat for augmentation of the paralyzed vocal fold. Each animal had surgically induced left vocal cord paralysis via sectioning of the recurrent laryngeal nerve, followed by injection of 0.1 to 0.2 ml of autologous fat into the paralyzed vocal fold. The animals were killed at 6 weeks, and at 4, 6, 8, and 12 months after the injection. Photographic and videolaryngoscopic data were obtained. Histologic studies of the larynges were performed. The results documented histologic viability and persistence of a portion of the injected adipose tissue graft at 8 months after the injection, but only minimal graft survival at 12 months. The outcome suggests that autologous lipoinjection has potential use for short-term (several months) augmentation of the paralyzed vocal cord. Further investigation is warranted before recommending this technique for such use or as an alternative to currently available long-term injectable laryngeal biomaterials.