Histopathologic study of human vocal fold mucosa unphonated over a decade

Abstract

Conclusion: Mechanotransduction caused by vocal fold vibration could possibly be an important factor in the maintenance of extracellular matrices and layered structure of the human adult vocal fold mucosa as a vibrating tissue after the layered structure has been completed. Objectives: Vocal fold stellate cells (VFSCs) in the human maculae flavae of the vocal fold mucosa are inferred to be involved in the metabolism of extracellular matrices of the vocal fold mucosa. Maculae flavae are also considered to be an important structure in the growth and development of the human vocal fold mucosa. Tension caused by phonation (vocal fold vibration) is hypothesized to stimulate the VFSCs to accelerate production of extracellular matrices. A human adult vocal fold mucosa unphonated over a decade was investigated histopathologically. Methods: Vocal fold mucosa unphonated for 11 years and 2 months of a 64-year-old male with cerebral hemorrhage was investigated by light and electron microscopy. Results: The vocal fold mucosae (including maculae flavae) were atrophic. The vocal fold mucosa did not have a vocal ligament, Reinke's space or a layered structure. The lamina propria appeared as a uniform structure. Morphologically, the VFSCs synthesized fewer extracellular matrices, such as fibrous protein and glycosaminoglycan. Consequently, VFSCs appeared to decrease their level of activity.

Keywords::

• Mechanotransduction
• vocal fold stellate cell
• macula flava
• larynx
• extracellular matrix

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.