Cholesteatoom

Cholesteatoom, or cholesteatoma, is an abnormal growth of keratinizing squamous epithelium in the middle ear and mastoid behind the tympanic membrane. It is not a true tumor but a destructive lesion that can erode surrounding bone. Cholesteatomas can be congenital or acquired. Congenital cholesteatoma arises within the temporal bone in the absence of a history of otitis media or tympanic membrane perforation. Acquired cholesteatoma typically develops in the setting of chronic otitis media and often from a retraction pocket of the pars flaccida or from a perforation, with accumulation of desquamated keratin debris.

Symptoms commonly include persistent unilateral otorrhea, often foul-smelling, and progressive conductive hearing loss. A whitish or pearly mass may be seen behind the tympanic membrane or in a retraction pocket on otoscopy. Patients may also report a sense of fullness, tinnitus, or vertigo as disease progresses. If the disease extends, it can involve the middle ear bones (ossicles), the mastoid, the facial nerve canal, the inner ear, or intracranial structures.

Diagnosis is based on clinical examination and audiometric assessment. Computed tomography (CT) of the temporal bone evaluates extent and bone erosion, particularly of the ossicles and mastoid. Magnetic resonance imaging (MRI) with diffusion-weighted sequences can aid in distinguishing cholesteatoma from other tissue and in detecting residual or recurrent disease.

Treatment is surgical and aimed at complete removal of the cholesteatoma and restoration or reconstruction of the tympanic membrane and ossicles when possible. Surgical approaches include canal wall up and canal wall down tympanomastoidectomy, with tympanoplasty and ossicular reconstruction as needed. Recurrence is possible, necessitating long-term surveillance with periodic otologic exams and imaging if indicated.