ENT · Otology
The facts most likely to be tested
Cholesteatoma is an abnormal keratinized squamous epithelial growth in the middle ear or mastoid, typically resulting from chronic eustachian tube dysfunction or recurrent otitis media.
The classic clinical presentation is painless otorrhea and progressive conductive hearing loss in a patient with a history of chronic ear disease.
Otoscopic examination reveals a retraction pocket of the tympanic membrane containing pearly white debris or granulation tissue.
Cholesteatomas are locally destructive due to the production of collagenases that cause ossicular chain erosion.
Complications include mastoiditis, facial nerve palsy, labyrinthitis, and intracranial abscesses due to bone erosion.
The definitive diagnostic imaging modality is a non-contrast CT scan of the temporal bone, which demonstrates a soft tissue mass with associated bony erosion.
The definitive treatment for symptomatic cholesteatoma is surgical excision (tympanomastoidectomy) to prevent further destruction of middle ear structures.
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A 42-year-old male presents to the clinic complaining of a persistent, foul-smelling discharge from his left ear for the past six months. He reports a history of frequent ear infections during childhood and notes a gradual decline in his hearing on that side. On physical examination, the left tympanic membrane shows a retraction pocket in the pars flaccida filled with pearly white, keratinous debris. There is no evidence of acute inflammation or fever. A Weber test lateralizes to the left ear, and a Rinne test shows bone conduction greater than air conduction on the left.
What is the most likely diagnosis?
Cholesteatoma
The patient's presentation of chronic painless otorrhea, conductive hearing loss, and the classic otoscopic finding of a pearly white mass in a retraction pocket is pathognomonic for cholesteatoma.
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Etiology / Epidemiology
Occurs due to chronic eustachian tube dysfunction or recurrent otitis media. Most common in patients with long-standing ear disease.
Clinical Manifestations
Painless otorrhea and conductive hearing loss. Look for pars flaccida retraction pocket with keratin debris.
Diagnosis
Diagnosis is clinical, but CT temporal bone is the gold standard for assessing extent and bony erosion.
Treatment
Surgical excision (tympanomastoidectomy) is the only definitive treatment. Avoid topical aminoglycosides if the tympanic membrane is perforated.
Prognosis
High risk of ossicular chain erosion and intracranial extension. Requires long-term surveillance for recurrence.
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Epidemiology & Etiology
Primarily affects patients with a history of chronic otitis media or eustachian tube dysfunction. It represents an abnormal growth of squamous epithelium in the middle ear or mastoid. Congenital forms exist but are rare compared to acquired cholesteatoma.
Pertinent Anatomy
The lesion typically originates in the pars flaccida of the tympanic membrane. It expands into the epitympanum, potentially involving the ossicular chain and mastoid air cells.
Pathophysiology
Chronic negative middle ear pressure creates a retraction pocket that traps desquamated keratin. This keratin debris accumulates, forming a mass that produces collagenases and osteoclasts. This leads to progressive bony erosion of the ossicles and surrounding structures.
Clinical Manifestations
Patients present with painless otorrhea and progressive conductive hearing loss. Physical exam reveals a pearly white mass behind the tympanic membrane or a crusty retraction pocket. Red flags include vertigo, facial nerve palsy, or post-auricular swelling, suggesting intracranial or labyrinthine invasion.
Diagnosis
Diagnosis is primarily clinical via otoscopy. CT temporal bone (without contrast) is the gold standard imaging modality to evaluate the extent of bony erosion and anatomical involvement. Audiometry is required to quantify the degree of conductive hearing loss.
Treatment
Definitive management is surgical excision via tympanomastoidectomy. Avoid topical aminoglycosides (e.g., gentamicin, neomycin) in the presence of a perforated tympanic membrane due to ototoxicity. Pre-operative antibiotics may be used for active infection, but they do not resolve the mass.
Prognosis
Untreated cases lead to permanent hearing loss and intracranial complications like meningitis or brain abscess. Recurrence is common, necessitating long-term surveillance with serial otoscopy or follow-up imaging.
Differential Diagnosis
Chronic Otitis Media: usually associated with purulent discharge and pain
Tympanosclerosis: presents as white calcific plaques, not a mass
Glomus Tumor: presents with pulsatile tinnitus and reddish-blue mass
Cerumen Impaction: easily removed, no bony erosion
Foreign Body: history of insertion, no chronic keratin accumulation