Goblet cells in the normal adult human larynx--studies on morphology, distribution and density

From 12 clinically and macroscopically normal larynges from adult persons all the mucosa was prepared and stained with PAS-alcian blue to study the morphology, distribution, and density of the goblet cells. In each larynx goblet cells were counted in 600 fields of 0.01768 mm2 mucosal surface, distributed on 18, 18 and 24 localities in the subglottis, glottis with the sinus of Morgagni, and supraglottis respectively. The goblet cells form a continuous pattern, comprising the entire subglottis, the anterior commissure, the sinus of Morgagni, the false vocal cords, vestibule of the larynx, and reaching to the cranial part of the laryngeal surface of the epiglottis. Another continuous, but goblet cell-free area extended from a couple of mm posterior to the anterior commissure, posteriorad on the cranial surface of the vocal cords, ary regions, aryepiglottic fold, the edge of the epiglottis, and 4-5 mm of the laryngeal surface of the epiglottic top, epiglottic vallecula, piriform recess, and the postcricoid region. Between the pseudostratified, ciliated columnar epithelium with goblet cells and the goblet cell-free stratified squamous epithelium there is a transitional epithelium in which the goblet cells alter from the 40 micron tall goblet cells characteristic of the respiratory tract epithelium to being quite flattened in order to disappear completely in the stratified squamous epithelium. The goblet cell density is significantly lower in the subglottis, viz. 125 cells per field, than in the glottis with the sinus of Morgagni and supraglottis, where the median density is 166 and 161 cells respectively per field. A possible correlation between the influence of the respiratory air upon the density of goblet cells and the complex anatomy of the larynx is discussed.