Abstract
EVIDENCE indicating the presence of secretory cells in normal middle ear mucosa in man and animals is increasing. Sadé1 reported the normal human middle ear lining to be a true mucosa that possesses cilia and secretes mucus. He also found, from mucosal biopsy in a case of serous otitis media, a PAS-negative glandular structure.2 Senturia and co-workers3 described goblet cells in the epithelium of the canine tympanic cavity. Lim et al,4 in a recent study, reported on the ultrastructure of the eustachian tube and middle ear mucosa in guinea pigs. They found two types of secretory cells: goblet cells in the epithelium of the eustachian tube and dark granulated cells in the transitional zone between the orifice of the tube and the epithelial lining of the bulla. These authors further stated that the latter cells resembled the serous secreting cells found in