Histologic structure and development of the laryngeal macula flava

Area of Science:

• Anatomy
• Histology
• Developmental Biology

Background:

• The laryngeal maculae flavae (MF) are known cellular condensations at vocal cord extremities.
• Their precise nature and function remain largely unknown in scientific literature.

Purpose of the Study:

• To perform a histomorphological analysis of the nature and development of the laryngeal maculae flavae (MF).
• To investigate the MF in human vocal cords from fetal development through adulthood.

Main Methods:

• Utilized light microscopy on 86 human larynges (12 weeks amenorrhea to adulthood).
• Employed hematoxylin and eosin, orcein, Alcian blue staining, and pS100 immunostaining.
• Analyzed fetal development in four distinct periods.

Main Results:

• Identified sequential development of posterior (13-15 WA) and anterior (16-18 WA) MF, defining the intermacular space.
• Observed development and maturation of fibrous structures (collagen, elastic fibers) between 20-33 WA and post-33 WA.
• Characterized adult MF structure as a concentric fibrous layer with a central cellular component.

Conclusions:

• Histological analysis supports a chondroid nature for the macular cells of the laryngeal maculae flavae.
• These findings challenge current understanding of the MF.
• The study discusses the role of the MF in vocal cord development.