Current treatment of vocal fold scarring.
OBJECTIVE
Vocal fold scarring still remains a therapeutic challenge, with the most problematic issue being the histologic changes that are primarily responsible for altering the viscoelasticity of the vocal fold mucosa. Optimal treatment for vocal fold scarring has not yet been established. To restore or regenerate damaged vocal folds, it is important to investigate the changes to the layer structure of the lamina propria. Tissue engineering and regenerative medicine may provide new strategies for the prevention and treatment of vocal fold scarring. Recent developments in this field are reviewed in the present article.


RESULTS
Histologic studies have revealed that hyaluronic acid, fibronectin, decorin, and various other extracellular matrix components, as well as collagen, may contribute to determining the vibratory properties of the vocal fold mucosa. Changes of these molecules are thought to affect the viscoelasticity of the scarred vocal folds. Based on such histologic findings, innovative approaches have been developed, including administration of hyaluronic acid into injured or scarred vocal folds. Other strategies that have recently shown advances include growth factor therapy and cell therapy using stem cells or mature fibroblasts. The effects of these new treatments have not fully been confirmed clinically, but there seems to be great therapeutic potential in such regenerative medical strategies.


CONCLUSIONS
Recent research has revealed the detailed histologic and rheologic changes related to vocal fold scarring. Based on these findings, various new therapeutic strategies have been developed in animal models using tissue engineering and regenerative medicine. However, no clinical trials have been performed, and more studies are necessary to establish the optimum modality.
Hirano
Shigeru
S
Department of Otolaryngology-Bronchoesophagology, Kyoto Medical Center, Fushimi, Kyoto, Japan. shirano@kyotolan.hosp.go.jp
D000903:Antibiotics, Antineoplastic / Q000627:therapeutic use; D002921:Cicatrix / Q000150:complications / Q000378:metabolism; D058575:Decorin; D004548:Elasticity; D005109:Extracellular Matrix / Q000378:metabolism; D016326:Extracellular Matrix Proteins; D005353:Fibronectins / Q000378:metabolism; D006801:Humans; D006820:Hyaluronic Acid / Q000378:metabolism; D007820:Laryngeal Mucosa / Q000378:metabolism; D016685:Mitomycin / Q000627:therapeutic use; D011509:Proteoglycans / Q000378:metabolism; D014783:Viscosity; D014827:Vocal Cords / Q000378:metabolism / Q000503:physiopathology*; D014832:Voice Disorders / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D014833:Voice Quality
D000903:Antibiotics, Antineoplastic; C546878:DCN protein, human; D058575:Decorin; D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D011509:Proteoglycans; D016685:Mitomycin; D006820:Hyaluronic Acid