Ultrastructure of the Middle Ear Mucosa and Effusion in Otitis Media

Abstract

Ultrastructural morphology of the promontrial mucosa was studied under an EM (Hitachi H-600) with an accelerating voltage of 75kV. of 12 specimens, the epithelial layer was present in 8 specimens and remaining 4 specimens lost their epithelial lining due to mechanical artefacts at the time of surgery. Six specimens out of 8 had a tall columnar type of epithelium and nonciliated cells had abundunt granules with or without dark-cores and bulging of macroapocrine secretion were often observed on the apical surface of these cells. Sometimes, in the enlarged intercellular space, several small spherical bodies, being enveloped by unit membrane, were found in this type of epithelium. These characteristic features of the epithelium seem to indicate hypersecretory state of the middle ear mucosa. Remining two specimens possessed a flat cuboidal type epithelium. Non ciliated cells had numerous microvilli on the surface but morphological features of secretory activities were absent in these cells. The dispersed ciliated cells were observed in both types of epithelium, showing some morphological changes such as shedding cilia and compound cilia.