3D Structure of the Macula Flava in the Human Vocal Fold

Abstract

Objective – To investigate the 3D structure of the macula flava in the human vocal fold.Material and Methods – The 3D structure of the macula flava in the human vocal fold was investigated by means of scanning electron microscopy using a chemical digestion method (modified sodium hydroxide maceration method) and the results compared with those obtained using light microscopy.Results – The macula flava of the human vocal fold comprised a dense mass of cells and extracellular matrices. Many cells were stellate in shape and possessed cytoplasmic processes. Extracellular matrices were composed of collagenous, reticular and elastic fibers, and ground substances (hyaluronic acid). Many fibers ran in various directions. The stellate cells were surrounded by these extracellular matrices. Amorphous materials were attached to the surface of the stellate cells. Extracellular matrices in the macula flava extended to those in the lamina propria of the vocal fold mucosa.Conclusion – Anterior and posterior maculae flavae in the human vocal fold mucosa are postulated to be involved in the metabolism of extracellular matrices, which are essential to the viscoelasticity of the lamina propria (the vibrating tissue) of the human adult vocal fold mucosa.