AAO-HNSF Primary Care Otolaryngology Handbook

OTITIS MEDIA

produces keratin. Over time, the keratinous debris can get caught in the pars flaccida retraction pocket . This can continue to accumulate, expanding the pocket, and is then called a cholesteatoma (Figure 4.4). Patients with cholesteatoma usually present with chronic ear drainage and hearing loss. Often these patients have been treated with ototopical antibiotic drops , and their drainage may have resolved, only to return when the treatment was stopped. If the choles-

Figure 4.4. Otoscopic view of left eardrum with

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teatoma is left untreated, it will continue to grow and erode bony structures . Possible sequelae include hearing loss secondary to necrosis of the long process of the incus, erosion into the lateral semi- circular canal (causing dizziness), sub-periosteal abscess, facial nerve palsy , meningitis, and brain abscess. The treatment for cholesteatoma is surgical removal. While excision gets rid of the cholesteatoma, the underlying Eustachian tube dysfunction is often still present. Thus, cholesteatoma has the propensity to recur. Once patients have undergone surgery for removal of a cholesteatoma, they will need continuous monitoring of their ear for the rest of their life. Another mechanism for cholesteatoma development is migration of squamous epithelium into the middle ear space through a hole in the eardrum. The perforation can come from a previous otitis media infection, a PE tube hole that did not heal, or trauma. Marginal perforations, or holes along the outer portion of the eardrum , are more likely to allow migration of epithelium than central perforations. Remember that the eardrum has three layers: cuboidal epithelium in the middle ear, a fibrous layer in the middle, and squamous epithelium on the outside. When there is a perforation, all three layers start to proliferate , but if the squamous layer and the cuboidal layer meet , the fibrous layer will stop . This can lead to a chronic perforation in which the middle ear is constantly being exposed to the outside and thus develops a low-grade inflammation.

cholesteatoma involving the pars flaccida . The white material is keratin filling the canal.

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