EXTERNAL AND MIDDLE EAR TRAUMA
Injuries localized to the external or middle ear include auricular hematoma, external auditory canal abrasion or laceration, tympanic membrane (TM) perforation, and ossicular chain dislocation. Local trauma to the TM and ossicles can occur by a penetrating injury with objects such as a cotton-tipped applicator, a bobby pin, a pencil, or a hot metal slag during welding. In addition, barotrauma, such as a slap to the ear or a blast injury, can cause a TM perforation or ossicular chain dislocation.
An auricular hematoma may present after a forceful blow to the external ear. It can be recognized as a tender swelling of the pinna that is fluctuant on palpation. The hematoma arises after the perichondrium is sheared off the cartilage of the auricle. This fluid accumulation needs prompt drainage to prevent chondronecrosis and to avoid a misshapen pinna, commonly known as a “cauliflower ear” or “wrestler’s ear.” After incision and drainage, a compression dressing is sutured through the pinna to bolster the skin and perichondrium against the auricular cartilage, preventing reaccumulation of the fluid. A course of empiric antibiotics is then recommended to prevent the cartilage from becoming infected.
B. External Auditory Canal Abrasion
Injuries to the external auditory canal most commonly occur when a patient is trying to remove his or her own earwax with a cotton-tipped applicator or bobby pin. The injury is usually a simple abrasion or laceration. Treatment consists of using an antimicrobial otic drop to prevent bacterial or fungal superinfection of the area. Alternately, there may be a localized area of blood collection underneath the skin of the external auditory canal, called a bulla. Perforating the tense bulla with a sharp pick often helps to reduce the patient’s discomfort. Patients with diabetes have a high risk of developing external otitis from this type of injury because of their poor microcirculation. These patients need to be followed up closely to verify wound healing.
C. Tympanic Membrane Perforation
A TM perforation can occur after penetrating injury or barotrauma. Patients usually complain of pain and hearing loss and the perforation can be diagnosed by otoscopy. It is important to note how much of the TM has been perforated. A central perforation does not involve the annulus of the eardrum, whereas a marginal perforation does. In addition, the Weber tuning-fork test should be performed to verify that it radiates to the affected ear, and the eyes should be checked for nystagmus. If the Weber test does not radiate to the affected ear and the patient has nystagmus, it is likely that stapes subluxation with sensorineural hearing loss has occurred. This ...