Otic Diseases

Acute Otitis Media. Acute otitis media is a suppurative infection of the middle-ear cavity. Facial nerve involvement is considered a complication of the infection and often occurs from direct pathogen invasion of a dehiscent portion of the facial nerve course, most commonly in the horizontal segment of the facial nerve. Treatment consists of systemic antibiotic therapy against the most common pathogens: Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae. Drainage of the infected fluid from the middle-ear space with a wide myringotomy is mandatory. If mastoiditis is present, a cortical mastoidectomy for drainage is indicated. Any sequestrum must be removed. Most physicians do not advocate facial nerve decompression in this setting.

Chronic Otitis Media. Chronic otitis media is an infection lasting more than six weeks with persistent otorrhea. Facial nerve involvement in this setting requires decompression of the facial nerve in addition to long-term antibiotics.

Cholesteatoma. Cholesteatoma is caused by squamous epithelium present within the middle-ear space. Cholesteatoma commonly causes bony erosion of the ossicles and can lead to serious complications such as fistulas, CSF otorrhea, meningitis, and facial paralysis. When facial paralysis occurs, urgent removal of the cholesteatoma and decompression of the facial nerve is indicated, much akin to cases of chronic otitis media.

Malignant Otitis Externa. Malignant otitis externa, also termed necrotizing otitis externa, is a skull-based osteomyelitis of otogenic origin. Patients present with severe otalgia, otorrhea, and cranial neuropathies. The facial nerve is the most common cranial nerve involved with studies ranging from 24% to 43% (74). The usual pathogen is Pseudomonas aeruginosa and often occurs in immunocompromised patients, typically with diabetes mellitus. Diagnosis is clinical, with an elevated sedimentation rate characteristic on serum evaluation (75). Patients also display increased tracer uptake on technetium or gallium nuclear medicine scans. Treatment requires aggressive blood sugar control and long-term antibiotic therapy directed toward P. aeruginosa. Hyperbaric oxygen has also proven beneficial in treating the chronic osteomyelitis. Prognosis is guarded, with mortality near 20% (74). Facial nerve recovery is also reported as quite poor in the literature, with little or no recovery of function, the rule. Surgical therapy is conservative with only minor debridement when necessary.

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