| Literature DB >> 955991 |
Abstract
The pathology and pathogenesis of chronic secretory otitis media is described on the bais of quantitative studies of the mucosa, using whole mounts as well as serial sections of normal and biopsy specimens. The pathogenetic is divided into three stages. The initial stage, i.e. the period from the action of the aetiological factor on the middle ear mucosa till the accumulation of mucous secretion, is characterized by inflammatory processes by way of vascular proliferation and dilatation and lymphocytic infiltration. These processes trigger hyperplasia and differentiation of the epithelial cells with subsequent metaplasia of the epithelium into pseudostratified columnar ciliated epithelium with significantly increased goblet cell density and formation of mucous glands. The secretion is predominantly exudative with an admixture of mucus. The secretory stage is dominated by secretion of mucus from active mucous glands and goblet cells, the number of which has been grossly raised. The secretion accumulating in the middle ear is chiefly mucous. During the degenerative stage mucus production abates, and the middle ear returns to normal provided that irreversible adhesive changes have not occurred. The decline in mucus production is due to degeneration and inactivation of the glands combined with decreasing goblet cell density. The epithelium normalizes into cubical epithelium in one or two layers, or through metaplasia changes into secretorily inactive stratified squamous epithelium. The aetiological role of the auditory tube and the importance of tubal function is discussed. The relationship between the ability of the mucosa to produce mucus and the capability of the tube to carry it away is found to be decisive for the clinical course and the severity of the disease.Entities:
Mesh:
Year: 1976 PMID: 955991
Source DB: PubMed Journal: HNO ISSN: 0017-6192 Impact factor: 1.284