Clinical Application of Regenerative Medicine to the Vocal Fold

Abstract

Regenerative medicine was a breakthrough in the late 20th century which provided potential to resolve refractory diseases. Research on regeneration of the larynx has also been carried out for the vocal fold, muscle, cartilage, and the recurrent laryngeal nerve. The present manuscript reviews the clinical application of regenerative medicine to the vocal fold. The target is irreversible diseases including vocal fold atrophy, scar, and sulcus that causes the vocal fold mucosa to be stiff. The chief pathology is atrophy and/or fibrosis of the superficial layer of the lamina propria (SLP). "Scaffolding" is a strategy in which the altered SLP is replaced with a regenerative scaffold such as atelocollagen or gelatin sponge, expecting creation of new healthy tissue in the scaffold. Atelocollagen implant into the scarred vocal fold has produced positive regenerative effects, but the effects were not consistent possibly because of lack of induction power of regeneration. Growth factors are strong tools that induce regeneration of several tissues. Basic fibroblast growth factor (bFGF) is a promising factor for vocal fold regeneration, and a commercial drug of bFGF is available in Japan. A clinical study of injection of bFGF into the vocal fold with atrophy or scar has demonstrated regenerative effects on the volume and viscoelastic property of the vocal fold.