Middle Ear Epithelium in the Presence of Experimental Effusion

Abstract

Serous effusions were experimentally induced in squirrel monkeys 24 hours after obstruction of their Eustachian tubes with fine silicone rubber sponge material. Electronmicroscopic study of the earliest epithelial changes of the mucoperiosteum revealed: (a) evidence of fluid flooding widened intercellular spaces; (b) deformation of non-ciliated and basal cells with cytoplasmic changes while ciliated cells maintained a near normal appearance; (c) ruptures of the basement membrane allowing fluid and cellular passage from the subepithelial to the epithelial layer.

These observations suggest that the serous fluid in this model resulted from transudation of vessels rather than active cellular secretion.