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An opening in the tympanic membrane usually caused by trauma. There are four general categories: compression injuries (the most common and usually the result of a blow to the ear); instrumentation injuries (the second most common, usually inadvertent, caused often by cotton swabs or bobby-pins); burn-slag injuries (frequently seen in industry, from hot metal from machines or welding); and blast injuries (usually seen during war or as a result of terrorist bombing). In the absence of infection, most traumatic tympanic membrane perforations heal spontaneously. Persistent perforation is usually a manifestation of tubotympanitis, an inflammation of the eustachian tube and tympanic cavity (middle ear). (From Paparella, Shumrick, Gluckman, and Meyerhoff: Otolaryngology, vol. II, 3d ed, pp1363-65)