The tympanic membrane (TM), or the eardrum, separates the external ear from the middle ear and perceives sound and sends the information to the brain. It serves as a key component of the tympano-ossicular system for sound transmission. As a thin sheet, the eardrum is highly sensitive to air pressure changes in external auditory canal. Trauma to the TM and the middle ear can result from a variety of causes like explosive blasts, thermal orcaustic burns, blunt or penetrating injuries, barotraumas, a slap against the ear or a blow by the fist, sport accidents, kiss ear, and others.
The most common symptoms are
- Aural fullness
- Hearing loss
- Bloody , purulent, or watery discharge
- Ear ache
Puretone Audiometry is done to determine the hearing loss. Pure sensorineural hearing loss is less common and is typically associated with direct or indirect inner ear trauma. Blast injuries may cause disruption of the round or oval window membranes and result in sensorineural loss, but patients with nonexplosive blast injuries have conductive hearingloss or usually have normal hearing.
A conservative management approach is generally adopted, except for those with bloody or watery discharge who receive oral systemic antibiotics to prevent infection. However, for those with existing purulent ear discharge, the middle ear infections are treated with appropriate ear drops, and the ears are subsequently kept dry. The patients are advised not to wet the ears.
Traumatic TM perforations have a tendency to heal spontaneously; more than 80% of all perforated TMs heal spontaneously, with relatively few requiring operative intervention . Large size of perforation and peripheral location of the defect have both been associated with lower rates of spontaneous healing. The curled edges may delay healing and even increase the likelihood of middle ear cholesteatoma ; secondary discharge often fails to close spontaneously .
A cutoff time point commonly used to consider a surgical closure procedure is 3 months in case the conservative management fails and the perforation persists.
Posted by Dr. Alok Banka