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Human adult maculae flavae are dense masses of cells and extracellular matrices
(Fig. 9.3) (Sato and Hirano 1995a; Sato et al. 2010a). The maculae flavae are
located at the anterior and posterior ends of the membranous portion of the bilateral
vocal folds. They are elliptical in shape and their size is approximately
1.5 mm × 1.5 mm × 1 mm (Sato and Hirano 1995a). The border between the maculae
flavae and the surrounding soft tissue is relatively clearly delineated (Fig. 9.2)
(Sato et al. 2003a).
The extracellular matrices of the human adult maculae flavae are composed of
glycoproteins and glycosaminoglycan and fibrillar proteins such as collagen fibers,
reticular fibers, and elastic fibers (Fig. 9.3). These extracellular matrices in the
maculae flavae extend to those in the lamina propria (Reinke’s space and vocal
ligament) of the human vocal fold mucosa (Sato and Hirano 1995a).
Fig. 9.3 Macula flava of the human adult vocal fold. (a) Human adult maculae flavae are dense
masses of cells (Hematoxylin and eosin stain). (b) There are many collagen fibers stained red and
elastic fibers stained black around the cells in the human adult maculae flavae (Elastic van Gieson
stain). (c) There are many collagen fibers stained red and reticular fibers (type III collagen) stained
black around cells in the human adult maculae flavae (Silver stain). (d) Much glycosaminoglycan
(hyaluronan, hyaluronic acid) is situated around the cells in the human adult maculae flavae
(Alcian blue stain, pH 2.5). Maculae flavae are strongly stained light blue with Alcian Blue at pH
2.5. Material in the maculae flavae that is strongly stained with Alcian Blue (pH 2.5) is digested by
hyaluronidase
K. Sato