Middle ear fluid.

Most middle ear effusions are preceded by an episode of acute otitis media. Craniofacial abnormalities predispose to such problems, and eustachian tube dysfunction is thought to be an important factor as well. Mechanical obstruction of the tube by inflammation or functional obstruction due to increased compliance leads to a failure to clear secretions produced by the middle ear. Removal of the obstruction is essential. If medical management does not clear the fluid, myringotomy with ventilating tubes may be required.