Macula flava in the vocal fold of human fetus.

The histological analysis of fetal vocal folds (in humans) in serial horizontal sections revealed a dense cell accumulation at the anterior and posterior ends of the vocal fold. Macula flava posterior was identified in all analysed specimens and macula flava anterior in those older than 18 weeks. Maculae flavae are composed of mesenchymal immature cells which gradually originate from cartilaginous cells of the arytenoid or mesenchymal immature cells of the anterior commissure tendon. Macula flava posterior presents the continuation of the arytenoid and there is no delineation between macula flava anterior and anterior commissure tendon. Since macula flava posterior extends its protrusion to the place of the most intensive connective tissue organization (which begins already in fetal life), it has been concluded that both maculae have an important influence to the specific organization and differentiation of connective tissue in the lamina propria of the fetal vocal fold.