Microscopic analysis of the mastoid bone in chronic serous otitis media.

The pathologic changes of the middle ear and mastoid bone mucosa in two pediatric patients with long standing chronic serous otitis media were studied by electron and light microscopy. The embryological development of the eustachian tube, middle ear cleft, and mastoid bone suggests a common physiological and anatomical continuity. The histological changes by light and electron microscopy in these patients demonstrates the metaplastic changes of the basal cell of the mucosa differentiating into mucous and keratin cells. These metaplastic changes are associated with the exudative process known as chronic serous otitis media.