MASTOIDITIS

inflammation of the mastoid process, which is a projection of the temporal bone just behind the ear. Mastoiditis is almost invariably secondary to acute or chronic otitis media (inflammation of the middle ear). In some instances the inflammation may spread into the mastoid antrum and cells, small cavities within the process, but when the infection is very severe, the whole middle ear cleft, which includes the mastoid region, is infected simultaneously. The narrow drainage channels from the antrum and cells are obstructed readily, and the degree to which the products of inflammation are penned within the mastoid antrum and cells determines the severity of the mastoid symptoms. The chief symptom is pain behind the ear and over the side of the head, and there may be a rise of temperature and pulse rate. Tenderness over the mastoid bone may be marked, and, as the condition develops, there is increased swelling of the tissues overlying the mastoid bone. The swelling may continue until a fluctuant abscess develops; this indicates that the infection has eroded the bone and destroyed its cortex (outer layer). In some circumstances the mastoiditis, instead of coming to the surface, may involve structures within the cranium and so give rise to complications. The most important of these are abscess without or within the dura mater covering the brain; infection and thrombosis (blood clot formation) of the lateral sinus (the large blood channel emptying into the internal jugular vein); and infection of the labyrinth (the inner ear) containing the balance and hearing apparatus. In addition, meningitis is a serious danger. Mastoiditis is treated by the early administration of antibiotics. At one time a frequent and dangerous disease, it is now rare because modern drugs can effectively arrest the preceding otitis media. In the few cases that do not respond to these remedies, surgical drainage with wide removal of diseased bone is necessary. Chronic mastoiditis results from unresolved attacks of acute mastoiditis and may produce any of the symptoms and signs already described. It can be treated during surgery for the cure of chronic otitis media.