[Vocal fold structure and speech pathologies].

Abstract

Our knowledge of vocal fold structure has profoundly evolved since the description by M. Hirano in 1974 of the laminar organization of the connective tissue of the human vocal fold, the lamina propria. The molecular composition of the extracellular matrix (ECM) of the lamina propria is essential in determining the viscoelastic properties of the tissue. This is particularly true in the superficial layer of the lamina propria (also called Reinke's space). With the epithelium, Reinke's space constitutes the vocal fold main vibrator. In normal subjects, the jelly like structure of the Reinke's space is due to a very loose fibrous scaffolding and to a balance between the interstitial proteins of the ECM: Proteoglycans like decorin and hyaluronic acid and glycoproteins like fibronectin. Vibratory trauma leads, in disease states, to molecular modification of the extracellular matrix of Reinke's space resulting in benign cordal lesions like nodules, submucosal fibrosis and vocal folds scars. Improving the knowledge of the homeostasis of Reinke's space ECM can lead to improvement of the therapeutic and prevention strategies of vocal fold benign lesions. The main histologic and viscoelastic characteristics, as well as surgical treatment of cordal nodular lesions and scars are described. The recent researches in the field of regeneration of Reinke's space are evoked.