Revisiting the Trabecular Meshwork in the Eyes of the Developing Human

Abstract

Background: The trabecular meshwork (TM) is a specialized tissue which is crucial to maintain ocular health (e.g. intraocular pressure) and to sustain optical clarity. Since collagen and elastic fibers are the primary structural components of the tissue, the characterization of these fibers in the fetal eye would advance our understanding of the basic morphology and further congenital studies related to the TM. Aims: To reveal the early development of the human fetal TM. Results: The results showed the presence of circular (radial) and longitudinal collagen fibers as well as trabecular cells in the TM by 12 weeks of gestation. By 26 weeks, the venous system connected with Schlemm’s canal and thin elastic fibers began to form. At birth, longitudinal collagen fibers linked with each other to form long strands. There was also evidence of an increase in circular (or radial) collagen fibers in the TM. Conclusion: The present study characterized the developmental and morphological changes in the genesis of the fetal TM in terms of growth in collagen and elastic fibers. The elastic fibers were found to exist in small quantity at birth, and, thus, any increase in these fibers to maturity is likely to occur after birth.