CHAPTER 57 ACUTE OTTTIS MEDIA An inflammatory reaction of the lining mucous membrane of the middle ear cleft in the whole or part of its extent from the Eustachian tube to the mastoid antrum and air cells is known as otitis media. The classification of the disease is generally related to the extent and degree of the inflammatory reaction in which there is either no formation of pus in the middle ear, non-suppurative otitis media, or one in which there is exudation of pus, suppurative otitis media. It should, however, be noted that an initially non-suppurative condition may proceed to a suppurative one. Acute and chronic forms of the disease are found. ACUTE NON-SUPPURATIVE OTITIS MEDIA (Acute Secretory Otitis Media) Acute non-suppurative otitis media, characterized by a non-purulent effusion in the middle ear, commonly follows Eugta^ianjtube obstruction. The majority of cases are associated with uppeFrespiratory infections of nasal origin or with allergic rhinitis. The latter may be a more common causal agent than expected, the symptoms appearing suddenly after exposure to, or ingestion of, some allergen to which the patient is sensitive. In other cases the predisposing factor may be an obstructive one such as adenoids or nasopharyngeal tumour. It may occur in patients who have a palatal paresis. In a few cases there may be no apparent cause. The effusion is either thin or viscid and is sterile on culture. SYMPTOMS. Earache is a more frequent symptom in children but when pain occurs ilnTusuaHy associated with Eustachian obstruction and dimi- nishes as the effusion increases in the middle ear and the negative middle ear pressure decreases. The leading symptomjsjdeafoess_jwhich is described in various ways, often ^Ja.blpcked or woolly feeling* in the ear. The degree of deafness is variable and improvement may occur when the ear is felt to 'crack* or 'pop'. An undue resonance of the patient's voice in his own ear, autophony, is a quite common complaint. Tinnitus is sometimes present and may be a troublesome aftermath in cases involving barotrauma. CLINICAL FEATURES. In the earliest stage with Eustachian obstruction the drumhead is indrawn or retracted (see Plate X, 2), and the short process of the malleus appears more prominent. With involvement of the tympanum, effusion is present and the appearances vary with the amount and character of the fluid. When the fluid does not fill the tympanum its upper margin may be seen as a hairline crossing the drumhead (see Plate X, 3); which has a yellow colour below the line, and a more normal 312