8 External Otitis Ear surgery is not often indicated for the sequelae of external otitis, but there are some important inflammatory ear diseases that can occur after trauma or surgical interventions—although they may also have no detectable origin. A list of the common forms of external otitis is given in Table 8.1.
Ear surgery is not often indicated for the sequelae of external otitis, but there are some important inflammatory ear diseases that can occur after trauma or surgical interventions—although they may also have no detectable origin. A list of the common forms of external otitis is given in Table 8.1.
|Chondrodermatitis apicis helicis|
|Bacterial and mycotic eczemas|
|Malignant external otitis (MEO) (temporal bone osteomyelitis)|
|Allergic skin reactions|
Two forms of a circumscribed external otitis may become surgically relevant. The first is chondrodermatitis apicis helicis, appearing as a small, hard nodule at the top of the helix (Fig. 8.1). This is a painful condition, the cause of which is unknown. Conservative, anti-inflammatory treatment is of no benefit; the treatment of choice is to excise the nodule, with immediate closure of the adjacent, mobilized skin. The specimen should be examined for a differential diagnosis against basal-cell carcinoma.
The second type of circumscribed external otitis is meatal furuncle. Aural pain-especially tragal pressure pain—in combination with swollen, red skin at the meatal entrance is typical. Since this infection of the hairy skin, starting as a form of folliculitis, is encouraged by mechanical irritation, thorough otoscopy should exclude the possibility that there is hidden otitis media or ear eczema that has led the patient to make inadequate attempts to clean the ear. Recurrent furuncles should raise a suspicion of diabetes mellitus. Conservative treatment, aiming at keratolysis, hyperemia, and disinfection using 6% salicylic acid in alcohol solution, is usually sufficient. Surgical interventions with abscess incision may be indicated in the presence of an inflammatory proliferation into the mastoid or parotid gland.
All types of injury may induce an ascending acute infection of the aural and meatal skin and underlying cartilage. A typical disease is aural erysipelas, produced by streptococci, in which there are sharp margins on the reddening and swelling skin, with fingerlike extensions (Fig. 8.2). The profile of the pinna is preserved. Erysipelas responds well to penicillin administration. Acute and chronic infection of the external ear by staphylococci is characterized by honeylike, yellow effusions, producing the typical impetigo eczema. Topical application of broad-spectrum antibiotics is the treatment of choice. If this or other forms of eczema show a tendency to reoccur, diabetes mellitus should be excluded. Occasionally, pyogenic granuloma